OT: Instant hot water heater spatters

Joerg

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May 25, 2013, 5:51:44 PM5/25/13

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We have one of those small 1/3rd gallon instant water heaters under the
sink, with its separate little tap on the sink. To make instant hot
drinks or to clean stuff. Worked flawlessly for many years. Recently it
started splattering, air bubbles come out. That wouldn't be so bad but
sometimes it splatters across the cup you are holding and it can burn
fingers. It's this one (3MB file):

http://www.insinkerator.com/en-us/Documents/WaterProducts/Hot1_ICU.pdf

I unplugged it, ran it for gallons, much more than the thing holds. It's
plumbed into the regular faucet next to it and that doesn't splatter. No
leaks anywhere. Given that I ran more water than could ever be in that
boiler plus short 1/4" branch-off line and it still has air bubbles I am
puzzled. Where could those come from? Why does the faucet on the same
supply line not produce any bubbles?

The sediment content of our water is very low, so that's unlikely.

--
Regards, Joerg

http://www.analogconsultants.com/

Jim Thompson

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May 25, 2013, 5:54:40 PM5/25/13

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On Sat, 25 May 2013 14:51:44 -0700, Joerg <inv...@invalid.invalid>
wrote:

Jon Kirwan

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May 25, 2013, 6:06:29 PM5/25/13

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On Sat, 25 May 2013 14:51:44 -0700, Joerg
<inv...@invalid.invalid> wrote:

Assuming the water is hot enough that steam can form, at all,
I think it's a given that there must be particulates of the
right size to be encouraging bubble formation somewhere and
that this is the change you are looking for. (I would guess
that the "air bubbles" are really "steam." So I would have
first thought about mineralization. But I gather you are
saying "no" to that. And I don't know if the water is hot
enough (together with altitude), besides.

Your test would seem to preclude air arriving from the
source, so the system itself remains the suspect.

Jon

Jim Thompson

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May 25, 2013, 6:12:16 PM5/25/13

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On Sat, 25 May 2013 14:54:40 -0700, Jim Thompson
<To-Email-Use-Th...@On-My-Web-Site.com> wrote:

>On Sat, 25 May 2013 14:51:44 -0700, Joerg <inv...@invalid.invalid>
>wrote:
>
>>We have one of those small 1/3rd gallon instant water heaters under the
>>sink, with its separate little tap on the sink. To make instant hot
>>drinks or to clean stuff. Worked flawlessly for many years. Recently it
>>started splattering, air bubbles come out. That wouldn't be so bad but
>>sometimes it splatters across the cup you are holding and it can burn
>>fingers. It's this one (3MB file):
>>
>>http://www.insinkerator.com/en-us/Documents/WaterProducts/Hot1_ICU.pdf
>>
>>I unplugged it, ran it for gallons, much more than the thing holds. It's
>>plumbed into the regular faucet next to it and that doesn't splatter. No
>>leaks anywhere. Given that I ran more water than could ever be in that
>>boiler plus short 1/4" branch-off line and it still has air bubbles I am
>>puzzled. Where could those come from? Why does the faucet on the same
>>supply line not produce any bubbles?
>>
>>The sediment content of our water is very low, so that's unlikely.
>
>Is the thermostat set too high, or failed, and the water is boiling,
>or near boiling such that, pressure drops when you open spout it
>bubbles?
>
> ...Jim Thompson

Which is the first item on the troubleshooting sheet ;-)

Martin Riddle

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May 25, 2013, 6:14:52 PM5/25/13

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On Sat, 25 May 2013 14:51:44 -0700, Joerg <inv...@invalid.invalid>
wrote:

The instructions say that steam will come out when first plugged in.
If it still steams, the thermostat needs to be adjusted.

Maybe the thermostat went south? Did you try to re-adjust it?
The water may be boiling .

Cheers

Joerg

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May 25, 2013, 6:40:25 PM5/25/13

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Jim Thompson wrote:
> On Sat, 25 May 2013 14:54:40 -0700, Jim Thompson
> <To-Email-Use-Th...@On-My-Web-Site.com> wrote:
>
>> On Sat, 25 May 2013 14:51:44 -0700, Joerg <inv...@invalid.invalid>
>> wrote:
>>
>>> We have one of those small 1/3rd gallon instant water heaters under the
>>> sink, with its separate little tap on the sink. To make instant hot
>>> drinks or to clean stuff. Worked flawlessly for many years. Recently it
>>> started splattering, air bubbles come out. That wouldn't be so bad but
>>> sometimes it splatters across the cup you are holding and it can burn
>>> fingers. It's this one (3MB file):
>>>
>>> http://www.insinkerator.com/en-us/Documents/WaterProducts/Hot1_ICU.pdf
>>>
>>> I unplugged it, ran it for gallons, much more than the thing holds. It's
>>> plumbed into the regular faucet next to it and that doesn't splatter. No
>>> leaks anywhere. Given that I ran more water than could ever be in that
>>> boiler plus short 1/4" branch-off line and it still has air bubbles I am
>>> puzzled. Where could those come from? Why does the faucet on the same
>>> supply line not produce any bubbles?
>>>
>>> The sediment content of our water is very low, so that's unlikely.
>> Is the thermostat set too high, or failed, and the water is boiling,
>> or near boiling such that, pressure drops when you open spout it
>> bubbles?
>>
>> ...Jim Thompson
>
> Which is the first item on the troubleshooting sheet ;-)
>
>

I know that but it's actually set lower than normal. Also, this does not
explain that I still get the same amount of bubbling and splattering
after having sent 3-4 gallons through the thing. By then it was totally
cold water.

Joerg

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May 25, 2013, 6:43:01 PM5/25/13

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Ok, but I've run gallons and gallons through the thing while unplugged.
It kept constantly throwing out the same number of (now cold) bubbles
per minute while the main faucet connected to the same line doesn't.

Joerg

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May 25, 2013, 6:46:34 PM5/25/13

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You can hear when it boils. I set the thermostat a bit lower when I
installed it many years ago. You can hear a brief onset of a boil on at
the end of every heating cycle but it turns off right at that point. The
factory setting had it making boiling noises much longer. This pattern
and the noise is still the same as years ago. But now we get bubbles,
even when the heater is unplugged and cold water streams out. No matter
how long I let it stream out.

Jon Elson

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May 25, 2013, 6:53:04 PM5/25/13

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Joerg wrote:

> I know that but it's actually set lower than normal. Also, this does not
> explain that I still get the same amount of bubbling and splattering
> after having sent 3-4 gallons through the thing. By then it was totally
> cold water.
>

The only thing I can think of is it is totally filled up
with calcium deposits, like a foam, and that is where all the
bubbles are hiding. You might try filling it with 50 %
vinegar solution and letting it sit for a while and see
if a huge amount of crud comes out. If so, repeat until
the crud is reduced to a reasonable level, then rinse
well before hooking the heater back up.

Jon

Joerg

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May 25, 2013, 7:03:09 PM5/25/13

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That would explain it, although our water is very low in minerals.
Getting vinegar into it would require me to undo the plumbing I guess.

The weird thing is that the sheer amount of bubbles already seems to be
more than such a tiny 1/3gal boiler could ever hold.

Jim Thompson

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May 25, 2013, 7:12:10 PM5/25/13

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On Sat, 25 May 2013 16:03:09 -0700, Joerg <inv...@invalid.invalid>
wrote:

Just replace it ;-)

Joerg

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May 25, 2013, 7:14:25 PM5/25/13

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Jim Thompson wrote:
> On Sat, 25 May 2013 16:03:09 -0700, Joerg <inv...@invalid.invalid>
> wrote:
>
>> Jon Elson wrote:
>>> Joerg wrote:
>>>
>>>
>>>> I know that but it's actually set lower than normal. Also, this does not
>>>> explain that I still get the same amount of bubbling and splattering
>>>> after having sent 3-4 gallons through the thing. By then it was totally
>>>> cold water.
>>>>
>>> The only thing I can think of is it is totally filled up
>>> with calcium deposits, like a foam, and that is where all the
>>> bubbles are hiding. You might try filling it with 50 %
>>> vinegar solution and letting it sit for a while and see
>>> if a huge amount of crud comes out. If so, repeat until
>>> the crud is reduced to a reasonable level, then rinse
>>> well before hooking the heater back up.
>>>
>> That would explain it, although our water is very low in minerals.
>> Getting vinegar into it would require me to undo the plumbing I guess.
>>
>> The weird thing is that the sheer amount of bubbles already seems to be
>> more than such a tiny 1/3gal boiler could ever hold.
>
> Just replace it ;-)
>

Tempted. But last time I did that I banged my head a lot. It's tight
down under the sink. Then there are those darn compression joints. Out
here they keep leaking ever so slightly until you torque them down to
white-knuckle level.

Rich Webb

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May 25, 2013, 7:18:52 PM5/25/13

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On Sat, 25 May 2013 14:51:44 -0700, Joerg <inv...@invalid.invalid>
wrote:

Dissolved gasses coming out of solution? Numbers and graphs here:
<http://www.engineeringtoolbox.com/air-solubility-water-d_639.html>

Could be that there has been a change in your upstream supply that is
bringing in a source with a higher than usual amount of dissolved
gasses. Heat it up and presto -- air bubbles.

Joerg

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May 25, 2013, 7:46:42 PM5/25/13

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I've suspected that. However, I just repeated the test that kind of says
it can't be: Ran it cold. Comes off the same line as the filtered water
faucet of same (small) diameter, both get filtered water. The
filtered-water faucet never has any bubbles, the hot-water dispenser
bubbles like crazy even well after all water in the tank has gone out
and fresh water comes in.

Jim Thompson

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May 25, 2013, 7:48:44 PM5/25/13

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On Sat, 25 May 2013 16:12:10 -0700, Jim Thompson
<To-Email-Use-Th...@On-My-Web-Site.com> wrote:

>On Sat, 25 May 2013 16:03:09 -0700, Joerg <inv...@invalid.invalid>
>wrote:
>
>>Jon Elson wrote:
>>> Joerg wrote:
>>>
>>>
>>>> I know that but it's actually set lower than normal. Also, this does not
>>>> explain that I still get the same amount of bubbling and splattering
>>>> after having sent 3-4 gallons through the thing. By then it was totally
>>>> cold water.
>>>>
>>> The only thing I can think of is it is totally filled up
>>> with calcium deposits, like a foam, and that is where all the
>>> bubbles are hiding. You might try filling it with 50 %
>>> vinegar solution and letting it sit for a while and see
>>> if a huge amount of crud comes out. If so, repeat until
>>> the crud is reduced to a reasonable level, then rinse
>>> well before hooking the heater back up.
>>>
>>
>>That would explain it, although our water is very low in minerals.
>>Getting vinegar into it would require me to undo the plumbing I guess.
>>
>>The weird thing is that the sheer amount of bubbles already seems to be
>>more than such a tiny 1/3gal boiler could ever hold.
>
>Just replace it ;-)
>
> ...Jim Thompson

Actually, bubbles even when cold suggests a pin-hole leak somewhere.
Maybe the valve is worn and leaks/sucks air when activated.

Jim Thompson

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May 25, 2013, 7:49:57 PM5/25/13

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On Sat, 25 May 2013 16:14:25 -0700, Joerg <inv...@invalid.invalid>
wrote:

That's where your air leak is.

Joerg

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May 25, 2013, 7:57:19 PM5/25/13

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Not anymore, else it would drip. You can't have air coming in when there
is 65psi in the water line.

Martin Riddle

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May 25, 2013, 8:03:40 PM5/25/13

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Not true, Its called the BernOn Sat, 25 May 2013 16:57:19 -0700, Joerg

Not true its called the Bernoulli effect, That can suck in air. if
there is enough pressure with the water flow stopped, it will seal
itself.

Cheers

Jim Thompson

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May 25, 2013, 8:03:50 PM5/25/13

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On Sat, 25 May 2013 16:57:19 -0700, Joerg <inv...@invalid.invalid>

So it's the valve. Or, another thought... does that gadget have a
vacuum break?

Joerg

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May 25, 2013, 8:03:49 PM5/25/13

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Ok, but then something should be wet under the sink. It's all under
pressure. AFAIK this unit doesn't have any over-pressure valve.

We do have a carbon cartridge water filter up front of it. Also feeds a
cold-water outlet and that does not show any bubbles. Could the filter
still have anything to do with it?

Jim Thompson

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May 25, 2013, 8:06:21 PM5/25/13

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Yep. Those damn compression fittings are notorious problem sources.
Actually the new purely plastic (of some kind) fittings are tight and
don't leak with just finger tightening.

Joerg

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May 25, 2013, 8:17:36 PM5/25/13

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> So it's the valve. ...

The question is: What valve? :-)

> ... Or, another thought... does that gadget have a
> vacuum break?
>

It's actually a very simple deal: Water line -> carbon filter ->
Y-splitter to cold water faucet and to this little water heater.

Then ... line goes up to push-button valve -> back down into bottom of
tank -> tank runs into curved outlet up top. That outlet has no valve,
just a pipe that must remain open and unobstructed at all times.

Jim Thompson

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May 25, 2013, 8:21:20 PM5/25/13

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On Sat, 25 May 2013 17:17:36 -0700, Joerg <inv...@invalid.invalid>

The one you push to dispense the hot water. Is it actually there or
does it activate a solenoid valve deep inside ?>:-}

Joerg

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May 25, 2013, 8:27:31 PM5/25/13

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No, it's a real mechanical push-button valve, incoming water line goes
in, out, and into tank. Since it's on the pressure side of things, if
that was leaky it should at least make a little bit of pee-pee. It's all
bone dry down there and also on top of the sink where the valve handle
comes out.

Jamie

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May 25, 2013, 8:46:50 PM5/25/13

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you have a hole in it somewhere or you're lacking water pressure.

Jamie

Jim Thompson

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May 25, 2013, 8:33:19 PM5/25/13

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On Sat, 25 May 2013 17:27:31 -0700, Joerg <inv...@invalid.invalid>

Does it leak if you keep it open for awhile? I just had to replace an
R/O faucet that was leaking only when pressed.

Greegor

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May 25, 2013, 8:39:46 PM5/25/13

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> Ok, but I've run gallons and gallons through the thing while unplugged.
> It kept constantly throwing out the same number of (now cold) bubbles
> per minute while the main faucet connected to the same line doesn't.

Air leak on outflow side of valve.

Joerg

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May 25, 2013, 8:41:29 PM5/25/13

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Nope. I tried again an hour ago. Ran it for five minutes to see if the
bubbling would stop this time (it didn't). Not a spot of moisture
anywhere it shouldn't be.

BTW, that print screen program you recommended worked like a champ. I
had a situation where I needed to do rapidfire storing with only very
few seconds until the procedure had to continue. Doing that via MS-Paint
or another graphics program would likely have resulted in cramps.

Joerg

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May 25, 2013, 8:43:33 PM5/25/13

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A hole would have to leak though. Water pressure is the usual 65psi, it
only drops (a lot) when the sprinklers are on.

Jim Thompson

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May 25, 2013, 8:46:18 PM5/25/13

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On Sat, 25 May 2013 17:41:29 -0700, Joerg <inv...@invalid.invalid>

Glad you like it! I'm not quite sure when/where I stumbled onto that
program, but it sure does work easily.

For others interested, it's at...

http://sourceforge.net/projects/greenshot/

Rich Webb

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May 25, 2013, 8:53:34 PM5/25/13

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On Sat, 25 May 2013 16:46:42 -0700, Joerg <inv...@invalid.invalid>
wrote:

How about this scenario: A model would be a eductor pump sucking
through a check valve. That is, a venturi with sufficiently low
pressure to pull in air while there is water flow but when pressure is
higher in the pipe than the outside, the check valve shuts, preventing
leakage.

The "venturi" could be there at the base of the spout and the "check
valve" a torn flap in one of the seals. When there's no flow, static
pressure holds it shut. Open the dispenser valve and there's enough
flow in that vicinity to suck in some air.

Kind of a reach, I know. ;-)

Cydrome Leader

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May 25, 2013, 10:30:47 PM5/25/13

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Joerg <inv...@invalid.invalid> wrote:
> We have one of those small 1/3rd gallon instant water heaters under the
> sink, with its separate little tap on the sink. To make instant hot
> drinks or to clean stuff. Worked flawlessly for many years. Recently it
> started splattering, air bubbles come out. That wouldn't be so bad but
> sometimes it splatters across the cup you are holding and it can burn
> fingers. It's this one (3MB file):
>
> http://www.insinkerator.com/en-us/Documents/WaterProducts/Hot1_ICU.pdf
>
> I unplugged it, ran it for gallons, much more than the thing holds. It's
> plumbed into the regular faucet next to it and that doesn't splatter. No
> leaks anywhere. Given that I ran more water than could ever be in that
> boiler plus short 1/4" branch-off line and it still has air bubbles I am
> puzzled. Where could those come from? Why does the faucet on the same
> supply line not produce any bubbles?
>
> The sediment content of our water is very low, so that's unlikely.

weird sputtering is probably an air leak. Check/replace any screens or
gaskets in the spigot and valve.

Air getting sucked back into a sink faucet is how the aerator works on the
regular part of your sink.

Jamie

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May 25, 2013, 11:16:05 PM5/25/13

to

A hole in the packing of the valve will suck in air.. A hole in the
nozzle will also do that. This is because of the venturi effects, you
won't see water coming out of those places but it'll suck air in.

Jamie

Mark

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May 25, 2013, 11:50:56 PM5/25/13

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if its not the heater and not the water source, is it something to do
with the faucet i.e. nozzle?

how does an aerator faucet work?

Mark

Jon Elson

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May 25, 2013, 11:59:10 PM5/25/13

to

Joerg wrote:

> Jon Elson wrote:

>>>
>> The only thing I can think of is it is totally filled up
>> with calcium deposits, like a foam, and that is where all the
>> bubbles are hiding. You might try filling it with 50 %
>> vinegar solution and letting it sit for a while and see
>> if a huge amount of crud comes out. If so, repeat until
>> the crud is reduced to a reasonable level, then rinse
>> well before hooking the heater back up.
>>
>
> That would explain it, although our water is very low in minerals.
> Getting vinegar into it would require me to undo the plumbing I guess.
>
> The weird thing is that the sheer amount of bubbles already seems to be
> more than such a tiny 1/3gal boiler could ever hold.
>

It may be making them on the spot. We have a hydronic heating
system here, so there are no air ducts for adding a humidifier to.
So, I built a water boiler with a ~100 W heating element on a
tank of water, with an automatic fill system. (Has a safety
shutdown, too, in case the auto fill gets stuck.) It is amazing
the amount of crud in the water, it fills the boiler with
off-white deposits in days. And, our domestic hot water heaters
get full of deposits and eventually have to be replaced. The
heat drives the ions out of solution.

Jon

Joerg

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May 26, 2013, 10:45:11 AM5/26/13

to

Aha. Now we are getting somewhere. I just have to figure out where,
maybe some sort of O-ring.

Although it would surprise me how that's possible with leaking hot some
water but who know.

Joerg

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May 26, 2013, 10:48:10 AM5/26/13

to

I took apart the old one where the heating element finally gave out
after well over a decade. It was clean as a whistle. I guess it greatly
depends where the water is coming from. Ours is very low in crud but
unfortunately high in chlorine.

Joerg

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May 26, 2013, 10:49:59 AM5/26/13

to

That's what Greegor also hinted at, I'll have to try to take that side
apart (unfortunately it's a unit, tank with outlet).

Joerg

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May 26, 2013, 10:52:06 AM5/26/13

to

:-)

I think Greegor and Jamie have a point, that sort of venturi could be at
the outlet. There is not water pressure to speak of on that one because
it's always open.

Joerg

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May 26, 2013, 10:53:39 AM5/26/13

to

This water heater doesn't have any screens but if may have an O-ring in
the outlet.

Robert Macy

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May 26, 2013, 11:41:52 AM5/26/13

to

On May 25, 4:03 pm, Joerg <inva...@invalid.invalid> wrote:
> Jon Elson wrote:
> > Joerg wrote:
>

> >> I know that but it's actually set lower than normal. Also, this does not
> >> explain that I still get the same amount of bubbling and splattering
> >> after having sent 3-4 gallons through the thing. By then it was totally
> >> cold water.
>

> > The only thing I can think of is it is totally filled up
> > with calcium deposits, like a foam, and that is where all the
> > bubbles are hiding. You might try filling it with 50 %
> > vinegar solution and letting it sit for a while and see
> > if a huge amount of crud comes out. If so, repeat until
> > the crud is reduced to a reasonable level, then rinse
> > well before hooking the heater back up.
>
> That would explain it, although our water is very low in minerals.
> Getting vinegar into it would require me to undo the plumbing I guess.
>
> The weird thing is that the sheer amount of bubbles already seems to be
> more than such a tiny 1/3gal boiler could ever hold.
>

> --
> Regards, Joerg
>
> http://www.analogconsultants.com/

If you're going to disconnect and flush, I'd use muriatic acid. That
stuff works! and, if quick enough may not hurt metal parts in there.

Spehro Pefhany

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May 26, 2013, 12:34:06 PM5/26/13

to

I'm always nervous about the potential for a flood if something is
weakened. It's easy to have damages that exceed $20-30K if nobody is
around when it happens.

Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
sp...@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

Jon Elson

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May 26, 2013, 1:06:25 PM5/26/13

to

Joerg wrote:

> I took apart the old one where the heating element finally gave out
> after well over a decade. It was clean as a whistle. I guess it greatly
> depends where the water is coming from. Ours is very low in crud but
> unfortunately high in chlorine.

Well, if the old one was clean inside, then this one probably
is, too. No idea, then, where the bubbles come from.

Jon

Joerg

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May 26, 2013, 1:12:19 PM5/26/13

to

Yeah, I think I'll pass on the muriatic acid. That's almost like
shooting a mosquito with a cannon. Then mosquito is going to be gone
alright but ...

rickman

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May 26, 2013, 9:16:32 PM5/26/13

to

You seem wedded to the idea that an air leak *has* to leak water. You
have evidence that there is air getting into the system, so why is the
lack of a water leak a problem? What possible explanation do you have?
Maybe it is a leak that seals when the pressure is high, but can suck
air when the pressure drops under use?

--

Rick

rickman

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May 26, 2013, 9:35:40 PM5/26/13

to

That is the idea of using vinegar. It is enough to remove some
minerals, but won't attack the metal as long as it doesn't remain in
contact with the metal too long. Some metals are subject to attack even
from vinegar like Aluminum. It can discolor if left in contact with
even weak acids for very long. It would take a long time to corrode it
structurally very much though.

--

Rick

Greegor

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May 26, 2013, 10:11:34 PM5/26/13

to

On May 26, 9:45 am, Joerg <inva...@invalid.invalid> wrote:
> Greegor wrote:
> >> Ok, but I've run gallons and gallons through the thing while unplugged.
> >> It kept constantly throwing out the same number of (now cold) bubbles
> >> per minute while the main faucet connected to the same line doesn't.
>
> > Air leak on outflow side of valve.
>
> Aha. Now we are getting somewhere. I just have to figure out where,
> maybe some sort of O-ring.
>
> Although it would surprise me how that's possible with leaking hot some
> water but who know.

You could be accidentally getting
a venturi effect on the outflow side.
Somebody else already mentioned the
venturi or Bernoulli principle which would
be pulling air into the outflow.

Air compressor powered paint sprayers
(Bink) pull paint out of the paint pot similarly,
though air and liquid are switched around.
(Both fluidic)

The quantity and shot gun behavior
of the air gives me doubts though.

Uwe Hercksen

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May 27, 2013, 7:01:38 AM5/27/13

to

Joerg schrieb:

> We have one of those small 1/3rd gallon instant water heaters under the
> sink, with its separate little tap on the sink. To make instant hot
> drinks or to clean stuff. Worked flawlessly for many years. Recently it
> started splattering, air bubbles come out. That wouldn't be so bad but
> sometimes it splatters across the cup you are holding and it can burn
> fingers. It's this one (3MB file):
>
> http://www.insinkerator.com/en-us/Documents/WaterProducts/Hot1_ICU.pdf
>
> I unplugged it, ran it for gallons, much more than the thing holds. It's
> plumbed into the regular faucet next to it and that doesn't splatter. No
> leaks anywhere. Given that I ran more water than could ever be in that
> boiler plus short 1/4" branch-off line and it still has air bubbles I am
> puzzled. Where could those come from? Why does the faucet on the same
> supply line not produce any bubbles?

Hello,

there is always some air soluted in water. Under pressure more air may
be soluted. Cold water may solute more air than hot one.
Temperature is rising, pressure is sinking, air bubbles are generated.
It's only physics.

Bye

Joerg

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May 27, 2013, 1:05:22 PM5/27/13

to

Yeah, but it also happens when the whole thing is cold.

bloggs.fred...@gmail.com

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May 27, 2013, 4:03:32 PM5/27/13

to

On Saturday, May 25, 2013 5:51:44 PM UTC-4, Joerg wrote:
> We have one of those small 1/3rd gallon instant water heaters under the
>
> sink, with its separate little tap on the sink. To make instant hot
>
> drinks or to clean stuff. Worked flawlessly for many years. Recently it
>
> started splattering, air bubbles come out. That wouldn't be so bad but
>
> sometimes it splatters across the cup you are holding and it can burn
>
> fingers. It's this one (3MB file):
>
>
>
> http://www.insinkerator.com/en-us/Documents/WaterProducts/Hot1_ICU.pdf
>
>
>
> I unplugged it, ran it for gallons, much more than the thing holds. It's
>
> plumbed into the regular faucet next to it and that doesn't splatter. No
>
> leaks anywhere. Given that I ran more water than could ever be in that
>
> boiler plus short 1/4" branch-off line and it still has air bubbles I am
>
> puzzled. Where could those come from? Why does the faucet on the same
>
> supply line not produce any bubbles?
>
>
>

> The sediment content of our water is very low, so that's unlikely.
>

It's cavitation, resulting from very complex hydrodynamics of flow through the heater together with material properties of the surfaces. It doesn't take an air leak. If you can't replace the heater core, replace the whole thing. The countertop one cup instant heater small appliances would probably be better because they don't require any plumbing.
http://en.wikipedia.org/wiki/Cavitation

rickman

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May 27, 2013, 6:02:44 PM5/27/13

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"Cavitation is the formation and then immediate implosion of cavities in
a liquid". Cavitation is a vacuum formed by the hydrodynamics of
propellers, impellers and similar objects. The bubbles disappear very
rapidly when they move away from the low pressure area. This is why
anyone even cares about cavitation. It produces a lot of noticeable
noise if you are trying to be quiet like a submarine and can erode
surfaces if it happens a lot.

Cavitation won't produce bubbles that last long enough to show up in the
water coming out of a faucet.

--

Rick

bloggs.fred...@gmail.com

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May 27, 2013, 7:15:29 PM5/27/13

to

On Monday, May 27, 2013 6:02:44 PM UTC-4, rickman wrote:

> Cavitation won't produce bubbles that last long enough to show up in the
>
> water coming out of a faucet.
>

You're wrong about that, know-it-all, cavitation is major issue for flow through a constriction like a valve port.

Jamie

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May 27, 2013, 9:00:37 PM5/27/13

to

Say what?

Jamie

rickman

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May 28, 2013, 6:35:48 PM5/28/13

to

Do you have anything to support your statement that I am wrong?
Cavitation bubbles are vacuum bubbles. They disappear very quickly.
That is not saying they don't exist in a valve, that is saying they
don't make it out of the faucet. They cause a problem when they
collapse and create a *very* high pressure jet resulting in erosion of
the surface.

I'm not a know it all. I don't know why you dispute facts. :) Why be
belligerent? If you disagree, give me some facts to support your point.
I quoted the article that you referenced. Was my quote incorrect?

--

Rick

Ralph Barone

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May 28, 2013, 8:52:41 PM5/28/13

to

Joerg <inv...@invalid.invalid> wrote:
> Jim Thompson wrote:

>> On Sat, 25 May 2013 16:14:25 -0700, Joerg <inv...@invalid.invalid>

>> wrote:
>>
>>> Jim Thompson wrote:
>>>> On Sat, 25 May 2013 16:03:09 -0700, Joerg <inv...@invalid.invalid>
>>>> wrote:
>>>>
>>>>> Jon Elson wrote:
>>>>>> Joerg wrote:
>>>>>>
>>>>>>
>>>>>>> I know that but it's actually set lower than normal. Also, this does not
>>>>>>> explain that I still get the same amount of bubbling and splattering
>>>>>>> after having sent 3-4 gallons through the thing. By then it was totally
>>>>>>> cold water.
>>>>>>>
>>>>>> The only thing I can think of is it is totally filled up
>>>>>> with calcium deposits, like a foam, and that is where all the
>>>>>> bubbles are hiding. You might try filling it with 50 %
>>>>>> vinegar solution and letting it sit for a while and see
>>>>>> if a huge amount of crud comes out. If so, repeat until
>>>>>> the crud is reduced to a reasonable level, then rinse
>>>>>> well before hooking the heater back up.
>>>>>>
>>>>> That would explain it, although our water is very low in minerals.
>>>>> Getting vinegar into it would require me to undo the plumbing I guess.
>>>>>
>>>>> The weird thing is that the sheer amount of bubbles already seems to be
>>>>> more than such a tiny 1/3gal boiler could ever hold.
>>>> Just replace it ;-)
>>>>

>>> Tempted. But last time I did that I banged my head a lot. It's tight
>>> down under the sink. Then there are those darn compression joints. Out
>>> here they keep leaking ever so slightly until you torque them down to
>>> white-knuckle level.
>>
>> That's where your air leak is.
>>
>
> Not anymore, else it would drip. You can't have air coming in when there
> is 65psi in the water line.

Note that on these water heaters, the valve is on the INLET side. The tank
is unpressurized and if the water boils in the tank it just comes out of
the faucet.

Ralph Barone

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May 28, 2013, 8:52:42 PM5/28/13

to

Joerg <inv...@invalid.invalid> wrote:
> We have one of those small 1/3rd gallon instant water heaters under the
> sink, with its separate little tap on the sink. To make instant hot
> drinks or to clean stuff. Worked flawlessly for many years. Recently it
> started splattering, air bubbles come out. That wouldn't be so bad but
> sometimes it splatters across the cup you are holding and it can burn
> fingers. It's this one (3MB file):
>
> http://www.insinkerator.com/en-us/Documents/WaterProducts/Hot1_ICU.pdf
>
> I unplugged it, ran it for gallons, much more than the thing holds. It's
> plumbed into the regular faucet next to it and that doesn't splatter. No
> leaks anywhere. Given that I ran more water than could ever be in that
> boiler plus short 1/4" branch-off line and it still has air bubbles I am
> puzzled. Where could those come from? Why does the faucet on the same
> supply line not produce any bubbles?
>
> The sediment content of our water is very low, so that's unlikely.

It's toast. Replace it. Mine did the same thing before it started leaking
water under the sink.

Dave M

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May 28, 2013, 9:36:36 PM5/28/13

to

On Sat, 25 May 2013 14:51:44 -0700, Joerg <inv...@invalid.invalid>

Joerg,
Several years ago, my house water heater started doing the exact same
thing. Lots of bubbling from the faucets, even though they were many
feet away from the water heater. The problem turned out to be a heating
element that had split open inside the tank, exposing the heater wire to
the water, and was boiling the water inside the tank. The circuit
breaker didn't trip. The water at the faucet was exceedingly hot...
don't know if was boiling temperature, but it surely spat and sputtered
like it was.

Fixed it with a new heater element. Never a moment's trouble from then
on..
Cheers,
Dave M

bloggs.fred...@gmail.com

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May 29, 2013, 10:40:40 AM5/29/13

to

Technically it may be called 'flashing' where the downstream pressure is low enough for the bubbles to remain vapor. The spatter is a relaxation effect where an airspace accumulates until enough back pressure develops to break it loose and thereby cause the spatter effect.

Joerg

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May 29, 2013, 10:51:39 AM5/29/13

to

Ok, but why then does the bubbling still happen with the heater
unplugged and everything totally cold? Still got to take the top apart,
but had some unplanned trips to the dentists. Restoration -> root went
off, big time -> root canal.

Martin Brown

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May 29, 2013, 11:55:19 AM5/29/13

to

On 25/05/2013 23:40, Joerg wrote:
> Jim Thompson wrote:

>> On Sat, 25 May 2013 14:54:40 -0700, Jim Thompson
>> <To-Email-Use-Th...@On-My-Web-Site.com> wrote:
>>
>>> On Sat, 25 May 2013 14:51:44 -0700, Joerg <inv...@invalid.invalid>
>>> wrote:
>>>
>>>> We have one of those small 1/3rd gallon instant water heaters under the
>>>> sink, with its separate little tap on the sink. To make instant hot
>>>> drinks or to clean stuff. Worked flawlessly for many years. Recently it
>>>> started splattering, air bubbles come out. That wouldn't be so bad but
>>>> sometimes it splatters across the cup you are holding and it can burn
>>>> fingers. It's this one (3MB file):
>>>>
>>>> http://www.insinkerator.com/en-us/Documents/WaterProducts/Hot1_ICU.pdf
>>>>
>>>> I unplugged it, ran it for gallons, much more than the thing holds. It's
>>>> plumbed into the regular faucet next to it and that doesn't splatter. No
>>>> leaks anywhere. Given that I ran more water than could ever be in that
>>>> boiler plus short 1/4" branch-off line and it still has air bubbles I am
>>>> puzzled. Where could those come from? Why does the faucet on the same
>>>> supply line not produce any bubbles?
>>>>
>>>> The sediment content of our water is very low, so that's unlikely.

>>> Is the thermostat set too high, or failed, and the water is boiling,
>>> or near boiling such that, pressure drops when you open spout it
>>> bubbles?
>>>
>>> ...Jim Thompson
>>
>> Which is the first item on the troubleshooting sheet ;-)

>
> I know that but it's actually set lower than normal. Also, this does not
> explain that I still get the same amount of bubbling and splattering
> after having sent 3-4 gallons through the thing. By then it was totally
> cold water.

That is also possibly a worst case scenario if there is dissolved air in
your water (or worse still methane from fracking).

Try slowly boiling some cold water on the stove to see how much air is
actually in there. I'm with JT that a broken thermostat is allowing
flash boiling of water when you open the tap as the root cause.

Measuring the temperature of the water in a plystyrene cup that comes
out might be illuminating. If we are right then it will be close to 99C.
(calibrated thermometer immersed to correct depth)

--
Regards,
Martin Brown

Joerg

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May 29, 2013, 12:50:13 PM5/29/13

to

There is not fracking done in the area. But anyhow, when I run water out
of a cold water tap on the same line there are no bubbles. With the cold
(unplugged) water heater there are always bubbles.

rickman

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May 29, 2013, 4:21:17 PM5/29/13

to

On 5/29/2013 10:40 AM, bloggs.fred...@gmail.com wrote:
>
> Technically it may be called 'flashing' where the downstream pressure is low enough for the bubbles to remain vapor. The spatter is a relaxation effect where an airspace accumulates until enough back pressure develops to break it loose and thereby cause the spatter effect.

How does this apply to cavitation? Cavitation bubbles are full of
nothing, possibly a very low pressure from the water vapor, but the
bubbles are not sustained once the very low pressure that created them
goes away. You are thinking of bubbles that are created when high
pressure is suddenly released. That is not cavitation. Cavitation
happens because water is not compressible (or expandable) and under the
right conditions there is not enough pressure to keep water on the
surface of a propeller or similar object. The vacuum bubbles form and
as soon as the pressure returns they collapse. It is the manner in
which they collapse that makes them interesting. They simply can't
continue to exist for very long, no different than a tin can sealed
after heating collapsing when cooled, just faster.

--

Rick

Paul Hovnanian P.E.

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May 29, 2013, 6:24:34 PM5/29/13

to

Joerg wrote:

> Uwe Hercksen wrote:
>>
[snip]

>> there is always some air soluted in water. Under pressure more air may
>> be soluted. Cold water may solute more air than hot one.
>> Temperature is rising, pressure is sinking, air bubbles are generated.
>> It's only physics.
>>
>
> Yeah, but it also happens when the whole thing is cold.

Air is getting into the thing some how. Most of these things don't work
under pressure. The way they work is:

The cold water feed (pressurized) runs through the counter top valve and
then back down into the tank. The output of the tank runs back up and then
out the spout at the counter top. When you open the valve, you are
admitting water into the tank, where it displaces heated water, pushing it
out the spout. When the valve is closed, the tank is just at atmospheric
pressure.

Any leaks downstream of the valve are not under supply pressure and might
even draw air in as the water flows. Its all cheap plastic tubing as well,
so check for cracks.

If the thermostat is set too high, the water will boil right out the spout
since there are no valves downstream of the tank. You should be able to see
that when its just sitting there.

--
Paul Hovnanian mailto:Pa...@Hovnanian.com
------------------------------------------------------------------
"The day Microsoft makes something that doesn't suck is probably the day
they start making vacuum cleaners" - Ernst Jan Plugge

josephkk

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May 30, 2013, 6:17:12 AM5/30/13

to

On Wed, 29 May 2013 09:50:13 -0700, Joerg <inv...@invalid.invalid> wrote:

>
>> That is also possibly a worst case scenario if there is dissolved air in
>> your water (or worse still methane from fracking).
>>
>> Try slowly boiling some cold water on the stove to see how much air is
>> actually in there. I'm with JT that a broken thermostat is allowing
>> flash boiling of water when you open the tap as the root cause.
>>
>> Measuring the temperature of the water in a plystyrene cup that comes
>> out might be illuminating. If we are right then it will be close to 99C.
>> (calibrated thermometer immersed to correct depth)
>>
>
>There is not fracking done in the area. But anyhow, when I run water out
>of a cold water tap on the same line there are no bubbles. With the cold
>(unplugged) water heater there are always bubbles.

Then there is a problem with the internal gaskets or seals, either way it
becomes remove and (re)install. New or repaired is your decision.

?-)

Martin Brown

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May 30, 2013, 7:24:00 AM5/30/13

to

On 30/05/2013 11:17, josephkk wrote:
> On Wed, 29 May 2013 09:50:13 -0700, Joerg <inv...@invalid.invalid> wrote:
>
>>
>>> That is also possibly a worst case scenario if there is dissolved air in
>>> your water (or worse still methane from fracking).
>>>
>>> Try slowly boiling some cold water on the stove to see how much air is
>>> actually in there. I'm with JT that a broken thermostat is allowing
>>> flash boiling of water when you open the tap as the root cause.
>>>
>>> Measuring the temperature of the water in a plystyrene cup that comes
>>> out might be illuminating. If we are right then it will be close to 99C.
>>> (calibrated thermometer immersed to correct depth)
>>
>> There is not fracking done in the area. But anyhow, when I run water out
>> of a cold water tap on the same line there are no bubbles. With the cold
>> (unplugged) water heater there are always bubbles.

Hard to see how it can leak air into the system without also leaking
water out but there might well be a bellows somewhere to allow for
thermal expansion when cold water is heated up in a closed system.

Our village hall one sputters a bit when it hasn't been used for a
while. But it quickly in a few seconds calms down an behaves normally.

>
> Then there is a problem with the internal gaskets or seals, either way it
> becomes remove and (re)install. New or repaired is your decision.
>
> ?-)

Another possibility is corrosion or something about the surface of the
heating element allowing dissolved gas to come out of solution.

If you run a tumbler of water from the cold tap is it milky with
dissolved gasses coming out of solution?

--
Regards,
Martin Brown

Joerg

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May 30, 2013, 2:02:16 PM5/30/13

to

Martin Brown wrote:
> On 30/05/2013 11:17, josephkk wrote:

[...]

>>
>> Then there is a problem with the internal gaskets or seals, either way it
>> becomes remove and (re)install. New or repaired is your decision.
>>
>> ?-)
>
> Another possibility is corrosion or something about the surface of the
> heating element allowing dissolved gas to come out of solution.
>
> If you run a tumbler of water from the cold tap is it milky with
> dissolved gasses coming out of solution?
>

No, it's clean. We fill the dog bucket from there and that's around two
gallons each time. Got big dogs :-)

Both are fed from the same carbon cartridge filter.

Cydrome Leader

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May 30, 2013, 3:59:18 PM5/30/13

to

Martin Brown <|||newspam|||@nezumi.demon.co.uk> wrote:
> On 30/05/2013 11:17, josephkk wrote:
>> On Wed, 29 May 2013 09:50:13 -0700, Joerg <inv...@invalid.invalid> wrote:
>>
>>>
>>>> That is also possibly a worst case scenario if there is dissolved air in
>>>> your water (or worse still methane from fracking).
>>>>
>>>> Try slowly boiling some cold water on the stove to see how much air is
>>>> actually in there. I'm with JT that a broken thermostat is allowing
>>>> flash boiling of water when you open the tap as the root cause.
>>>>
>>>> Measuring the temperature of the water in a plystyrene cup that comes
>>>> out might be illuminating. If we are right then it will be close to 99C.
>>>> (calibrated thermometer immersed to correct depth)
>>>
>>> There is not fracking done in the area. But anyhow, when I run water out
>>> of a cold water tap on the same line there are no bubbles. With the cold
>>> (unplugged) water heater there are always bubbles.
>
> Hard to see how it can leak air into the system without also leaking
> water out but there might well be a bellows somewhere to allow for

It might be hard to imagine this happening, but the fact is it does. A
leak doesn't always mean you have water spraying all over the place.

A vacuum breaker is an example of this. They can "leak" air, but not water
when working correctly. They can even do both at the same time. When
they're broken they do all sorts of great things.

Paul Hovnanian P.E.

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May 30, 2013, 10:05:35 PM5/30/13

to

Martin Brown wrote:

[snip]

>
> Hard to see how it can leak air into the system without also leaking
> water out but there might well be a bellows somewhere to allow for
> thermal expansion when cold water is heated up in a closed system.

The heating tank isn't closed in many of these. It is at atmospheric
pressure. The counter-top valve admits cold water into the tank. The tank
output is always open through a tube to the outlet over the sink.

So its possible that any flow through the heated part of the system will
result in lower pressure which will draw air in.

--
Paul Hovnanian mailto:Pa...@Hovnanian.com
------------------------------------------------------------------

"Vegetarian" - Indian word for "lousy hunter"

Martin Brown

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May 31, 2013, 4:32:29 AM5/31/13

to

On 31/05/2013 03:05, Paul Hovnanian P.E. wrote:
> Martin Brown wrote:
>
> [snip]
>>
>> Hard to see how it can leak air into the system without also leaking
>> water out but there might well be a bellows somewhere to allow for
>> thermal expansion when cold water is heated up in a closed system.
>
> The heating tank isn't closed in many of these. It is at atmospheric
> pressure. The counter-top valve admits cold water into the tank. The tank
> output is always open through a tube to the outlet over the sink.
>
> So its possible that any flow through the heated part of the system will
> result in lower pressure which will draw air in.

That isn't how the ones I am familiar with in the UK work. There is
quite a complex piece of plumbing under the bench along the lines of:

mains water feed
[non-return-valve]
[pressure reducer]
[expansion bellows]
[pressure gauge]
[waterheater]
[emergency overflow pipe and/or bursting disk]
[tap]

And fairly stern warnings with the kit that bad things will happen if
there isn't sufficient length of pipe and/or bellows. Our mains water
pressure is very high (especially so at night) and requires the full
monty to work. You can get away with a simpler setup elsewhere.

There are also two main sorts of instant hot water. The ones where there
is a reservoir of already very hot water boosted on demand and the other
where an insanely high current heater takes cold water right up to the
set point continuously. I am no longer sure which Joerg has.

I wish our VH had the latter since users sometimes run the hot tap
wasting a tank full of hot water which then takes a while to recover.
The sink is only 10' from the main 3 phase high capacity electricity
distribution box but then it was installed by a plumber...

--
Regards,
Martin Brown

whit3rd

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May 31, 2013, 3:40:34 PM5/31/13

to

On Monday, May 27, 2013 3:02:44 PM UTC-7, rickman wrote:

[on air/liquid spatter from a hot water nozzle]

> > http://en.wikipedia.org/wiki/Cavitation
>
> "Cavitation is the formation and then immediate implosion of cavities in
> a liquid".

> Cavitation won't produce bubbles that last long enough to show up in the
>
> water coming out of a faucet.

I'll disagree with the Wikipedia definition here. The implosion of
cavities is IMPORTANT, but the cavity formation alone constitutes cavitation.

When the liquid is recently released from a pressurized water system,
it can be so far out of equilibrium with atmospheric pressure that
the cavitation bubble fills with dissolved air too fast to
allow it to do the implosion.

So, cavitation combined with excess of dissolved gases can
make for bubbles far in excess of what a noncavitating flow
would produce.

Jasen Betts

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May 31, 2013, 7:20:17 PM5/31/13

to

If the element split open and exposed the wire you'd get brown's gas in
the output that'd cause sputtering even when cold.

--
⚂⚃ 100% natural

--- news://freenews.netfront.net/ - complaints: ne...@netfront.net ---

rickman

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Jun 1, 2013, 12:00:32 PM6/1/13

to

Please tell me what is your source for this information?

BTW, I don't consider Wikipedia to be a primary reference, just like
Wikipedia. They won't allow you to quote one wiki page from another...
That says something significant.

--

Rick

Joerg

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Jun 2, 2013, 10:58:14 AM6/2/13

to

Ok, but not if it is unplugged, right?

ehric...@gmail.com

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Feb 11, 2015, 10:14:48 PM2/11/15

to

On Saturday, May 25, 2013 at 5:51:44 PM UTC-4, Joerg wrote:
> We have one of those small 1/3rd gallon instant water heaters under the
> sink, with its separate little tap on the sink. To make instant hot
> drinks or to clean stuff. Worked flawlessly for many years. Recently it
> started splattering, air bubbles come out. That wouldn't be so bad but
> sometimes it splatters across the cup you are holding and it can burn
> fingers. It's this one (3MB file):
>
> http://www.insinkerator.com/en-us/Documents/WaterProducts/Hot1_ICU.pdf
>
> I unplugged it, ran it for gallons, much more than the thing holds. It's
> plumbed into the regular faucet next to it and that doesn't splatter. No
> leaks anywhere. Given that I ran more water than could ever be in that
> boiler plus short 1/4" branch-off line and it still has air bubbles I am
> puzzled. Where could those come from? Why does the faucet on the same
> supply line not produce any bubbles?
>
> The sediment content of our water is very low, so that's unlikely.
>

> --
> Regards, Joerg
>
> http://www.analogconsultants.com/

See: <http://terrylove.com/forums/index.php?threads/instant-hot-water-dispenser-problem.40301/>

Ralph Barone

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Feb 11, 2015, 10:19:52 PM2/11/15

to

Typical fix is tear it out and replace it. They don't last long.

Baron

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Feb 12, 2015, 5:13:35 AM2/12/15

to

ehric...@gmail.com prodded the keyboard

Its likely that there is a perforation in the heating element. Its
essentially scrap now. Check the earth leakage, it should be 10M or
more.

--
Best Regards:
Baron.

Jon Elson

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Feb 12, 2015, 3:07:11 PM2/12/15

to

Baron wrote:

> Its likely that there is a perforation in the heating element. Its
> essentially scrap now. Check the earth leakage, it should be 10M or
> more.
>
>

If it does NOT show leakage (electrical or water) you could try
getting a little vinegar into it, let it sit for half an hour, then
flush with water. If crud comes out, repeat until no more crud is
produced.

Solubility of various salts decreases as the water gets hot, so salts
precipitate out of even soft water in these heated tanks. It builds up
over the years if not dissolved out. Vinegar works REALLY well at
cleaning heated tanks.

Jon

Dave M

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Feb 12, 2015, 4:45:35 PM2/12/15

to

I agree with the perforated heating element theory. I've had two heating
elements in my home water heater do the exact same thing (years apart... not
at the same time). Bubbles, steam, etc. When I removed the elements, the
outer steel cladding covering the element was split, exposing about 2 nches
of the resistance wire inside.

New elements solved the problem.

Dave M

Jim Thompson

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Feb 12, 2015, 5:34:02 PM2/12/15

to

On Sat, 25 May 2013 14:51:44 -0700, Joerg <inv...@invalid.invalid>

wrote:

>We have one of those small 1/3rd gallon instant water heaters under the
>sink, with its separate little tap on the sink. To make instant hot
>drinks or to clean stuff. Worked flawlessly for many years. Recently it
>started splattering, air bubbles come out. That wouldn't be so bad but
>sometimes it splatters across the cup you are holding and it can burn
>fingers. It's this one (3MB file):
>
>http://www.insinkerator.com/en-us/Documents/WaterProducts/Hot1_ICU.pdf
>
>I unplugged it, ran it for gallons, much more than the thing holds. It's
>plumbed into the regular faucet next to it and that doesn't splatter. No
>leaks anywhere. Given that I ran more water than could ever be in that
>boiler plus short 1/4" branch-off line and it still has air bubbles I am
>puzzled. Where could those come from? Why does the faucet on the same
>supply line not produce any bubbles?
>
>The sediment content of our water is very low, so that's unlikely.

Lasse Langwadt Christensen

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Feb 12, 2015, 5:51:45 PM2/12/15

to

Den torsdag den 12. februar 2015 kl. 23.34.02 UTC+1 skrev Jim Thompson:
> On Sat, 25 May 2013 14:51:44 -0700, Joerg <inv...@invalid.invalid>
> wrote:
>
> >We have one of those small 1/3rd gallon instant water heaters under the
> >sink, with its separate little tap on the sink. To make instant hot
> >drinks or to clean stuff. Worked flawlessly for many years. Recently it
> >started splattering, air bubbles come out. That wouldn't be so bad but
> >sometimes it splatters across the cup you are holding and it can burn
> >fingers. It's this one (3MB file):
> >
> >http://www.insinkerator.com/en-us/Documents/WaterProducts/Hot1_ICU.pdf
> >
> >I unplugged it, ran it for gallons, much more than the thing holds. It's
> >plumbed into the regular faucet next to it and that doesn't splatter. No
> >leaks anywhere. Given that I ran more water than could ever be in that
> >boiler plus short 1/4" branch-off line and it still has air bubbles I am
> >puzzled. Where could those come from? Why does the faucet on the same
> >supply line not produce any bubbles?
> >
> >The sediment content of our water is very low, so that's unlikely.
>
> Anyone have information on the "instant" heaters under your sink for
> the _regular_ hot water, providing hot water long enough for the hot
> water from the water heater to arrive?
>

I now you can get self regulating heat tape set for 50'C mean to be
used to get instant hot water at taps that are far from the heater

I think it is mostly meant for add-ons, isn't most hot water installations
made as a circulating loop so the water is almost instantly hot?

-Lasse

Martin Riddle

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Feb 12, 2015, 7:33:07 PM2/12/15

to

On Thu, 12 Feb 2015 15:33:58 -0700, Jim Thompson
<To-Email-Use-Th...@On-My-Web-Site.com> wrote:

>On Sat, 25 May 2013 14:51:44 -0700, Joerg <inv...@invalid.invalid>
>wrote:
>
>>We have one of those small 1/3rd gallon instant water heaters under the
>>sink, with its separate little tap on the sink. To make instant hot
>>drinks or to clean stuff. Worked flawlessly for many years. Recently it
>>started splattering, air bubbles come out. That wouldn't be so bad but
>>sometimes it splatters across the cup you are holding and it can burn
>>fingers. It's this one (3MB file):
>>
>>http://www.insinkerator.com/en-us/Documents/WaterProducts/Hot1_ICU.pdf
>>
>>I unplugged it, ran it for gallons, much more than the thing holds. It's
>>plumbed into the regular faucet next to it and that doesn't splatter. No
>>leaks anywhere. Given that I ran more water than could ever be in that
>>boiler plus short 1/4" branch-off line and it still has air bubbles I am
>>puzzled. Where could those come from? Why does the faucet on the same
>>supply line not produce any bubbles?
>>
>>The sediment content of our water is very low, so that's unlikely.
>
>Anyone have information on the "instant" heaters under your sink for
>the _regular_ hot water, providing hot water long enough for the hot
>water from the water heater to arrive?
>
> ...Jim Thompson

Some require a huge amount of juice. You may have to upgrade your
service panel another 100Amps.

Why is this thread still alive?

Cheers

Jim Thompson

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Feb 12, 2015, 7:59:22 PM2/12/15

to

No circuits to talk about >:-}

k...@attt.bizz

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Feb 12, 2015, 8:05:25 PM2/12/15

to

That's pretty damned wasteful. A small tank heater is a lot easier to
insulate. I plan un putting two downstairs, one for the master bath
and the other for the kitchen.

>I think it is mostly meant for add-ons, isn't most hot water installations
>made as a circulating loop so the water is almost instantly hot?
>

They're double wasteful (two pipes). Most just move the water heater
closer to the point of use.

I have no idea why they put our water heater in the garage when there
is over 2K sq.ft. of unfinished basement it could easily get lost in.

k...@attt.bizz

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Feb 12, 2015, 8:21:24 PM2/12/15

to

On Thu, 12 Feb 2015 19:33:05 -0500, Martin Riddle
<marti...@verizon.net> wrote:

Nah, they're only about 2KW. They're being fed by the main water
heater so they don't have to raise the temperature much.

>Why is this thread still alive?
>

Because people are still answering it?

Martin Riddle

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Feb 12, 2015, 8:37:34 PM2/12/15

to

Good point, I was thinking of a true on-demand heater.

Cheers

pinku...@gmail.com

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Nov 25, 2017, 5:10:37 AM11/25/17

to

Is it a faulty thermostat?

rober...@gmail.com

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Apr 7, 2018, 6:32:22 AM4/7/18

to

On Saturday, November 25, 2017 at 10:10:37 AM UTC, pinku...@gmail.com wrote:
> Is it a faulty thermostat?

have now joined the many with the same problem , didn't expect it to last for ever but thought 5yrs at least , I had the idea it might be the vent pipe restricted , if it was able to vent enough it wouldn't blow out the water left in the supply pipe upstream from the valve , any thoughts ?

Sjouke Burry

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Apr 7, 2018, 3:02:40 PM4/7/18

to

Thermostat wrong --> water boils --> sputtering starts.

Jim Thompson

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Apr 7, 2018, 5:22:55 PM4/7/18

to

Back in the days "BK" (before Keurig), I suspected that a too-high
thermostat setting results in sudden "boiling"/sputtering as the
pressure suddenly drops when the valve is opened.

Later I've come to believe it's simply a surface roughening of the
heater tubing due to mineral content... there ain't no such thing as
"pure" water, "softened" or not.

I don't know how many years we've had our Keurig dispenser, probably
at least 10... but we've always fed it R/O water... yet every few
months a vinegar rinse cycle.

| STV, Queen Creek, AZ 85142 Skype: skypeanalog | |

To those of us in my age bracket...

GREEN means inexperienced and/or incompetent.

gnuarm.del...@gmail.com

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Apr 7, 2018, 6:07:49 PM4/7/18

to

On Saturday, April 7, 2018 at 5:22:55 PM UTC-4, Jim Thompson wrote:
> On Sat, 07 Apr 2018 21:02:35 +0200, Sjouke Burry
> <burrynu...@ppllaanneett.nnll> wrote:
>
> >On 7-4-2018 12:32, rober...@gmail.com wrote:
> >> On Saturday, November 25, 2017 at 10:10:37 AM UTC, pinku...@gmail.com wrote:
> >>> Is it a faulty thermostat?
> >>
> >> have now joined the many with the same problem , didn't expect it to last for ever but thought 5yrs at least , I had the idea it might be the vent pipe restricted , if it was able to vent enough it wouldn't blow out the water left in the supply pipe upstream from the valve , any thoughts ?
> >>
> >Thermostat wrong --> water boils --> sputtering starts.
>
> Back in the days "BK" (before Keurig), I suspected that a too-high
> thermostat setting results in sudden "boiling"/sputtering as the
> pressure suddenly drops when the valve is opened.
>
> Later I've come to believe it's simply a surface roughening of the
> heater tubing due to mineral content... there ain't no such thing as
> "pure" water, "softened" or not.
>
> I don't know how many years we've had our Keurig dispenser, probably
> at least 10... but we've always fed it R/O water... yet every few

> months a vinegar rinse cycle.nt.

RO water? I don't think RO makes water. Water is H2O. I guess that's a euphemism for alcohol? I wouldn't put alcohol through a Keurig unit. That could be dangerous.

Rick C.

Jim Thompson

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Apr 7, 2018, 7:21:27 PM4/7/18

to

Are you living in a cave? "R/O" is reverse-osmosis processed water...
usually done after the softener loop.

gnuarm.del...@gmail.com

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Apr 8, 2018, 1:00:58 AM4/8/18

to

On Saturday, April 7, 2018 at 7:21:27 PM UTC-4, Jim Thompson wrote:
> On Sat, 7 Apr 2018 15:07:44 -0700 (PDT),
> gnuarm.del...@gmail.com wrote:
>
> >On Saturday, April 7, 2018 at 5:22:55 PM UTC-4, Jim Thompson wrote:
> >> On Sat, 07 Apr 2018 21:02:35 +0200, Sjouke Burry
> >> <burrynu...@ppllaanneett.nnll> wrote:
> >>
> >> >On 7-4-2018 12:32, rober...@gmail.com wrote:
> >> >> On Saturday, November 25, 2017 at 10:10:37 AM UTC, pinku...@gmail.com wrote:
> >> >>> Is it a faulty thermostat?
> >> >>
> >> >> have now joined the many with the same problem , didn't expect it to last for ever but thought 5yrs at least , I had the idea it might be the vent pipe restricted , if it was able to vent enough it wouldn't blow out the water left in the supply pipe upstream from the valve , any thoughts ?
> >> >>
> >> >Thermostat wrong --> water boils --> sputtering starts.
> >>
> >> Back in the days "BK" (before Keurig), I suspected that a too-high
> >> thermostat setting results in sudden "boiling"/sputtering as the
> >> pressure suddenly drops when the valve is opened.
> >>
> >> Later I've come to believe it's simply a surface roughening of the
> >> heater tubing due to mineral content... there ain't no such thing as
> >> "pure" water, "softened" or not.
> >>
> >> I don't know how many years we've had our Keurig dispenser, probably
> >> at least 10... but we've always fed it R/O water... yet every few
> >> months a vinegar rinse cycle.nt.
> >
> >RO water? I don't think RO makes water. Water is H2O. I guess that's a euphemism for alcohol? I wouldn't put alcohol through a Keurig unit. That could be dangerous.
> >
> >Rick C.
>
> Are you living in a cave? "R/O" is reverse-osmosis processed water...
> usually done after the softener loop.

No, I don't live in a cave. I just don't know every single abbreviation invented by anyone, anywhere. It's just plain stupid to use abbreviations so commonly when they aren't obvious from context. You may have thought what you wrote was clear, but it wasn't. Thanks for the clarification.

Rick C.

stavi...@gmail.com

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Jun 15, 2020, 8:53:13 PM6/15/20

to

I took apart the hot water reservoir. It was filled with oatmeal looking gunk on the bottom and I believe that this was causing the sputtering. Hate to think that I had been drinking this. Tossed it out.

Ricketty C

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Jun 15, 2020, 10:56:31 PM6/15/20

to

On Monday, June 15, 2020 at 8:53:13 PM UTC-4, stavi...@gmail.com wrote:
> I took apart the hot water reservoir. It was filled with oatmeal looking gunk on the bottom and I believe that this was causing the sputtering. Hate to think that I had been drinking this. Tossed it out.

You are always drinking it. Those are just dissolved minerals. Mostly they are either ok or even good for you. But there's a lot more in the water these days that we can't get rid of without expensive methods.

Those contaminants don't necessarily precipitate out in the boiling water.

--

Rick C.

- Get 1,000 miles of free Supercharging
- Tesla referral code - https://ts.la/richard11209

Uwe Bonnes

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Jun 16, 2020, 7:48:24 AM6/16/20

to

Ricketty C <gnuarm.del...@gmail.com> wrote:
> On Monday, June 15, 2020 at 8:53:13 PM UTC-4, stavi...@gmail.com wrote:
>> I took apart the hot water reservoir. It was filled with oatmeal looking gunk on the bottom and I believe that this was causing the sputtering. Hate to think that I had been drinking this. Tossed it out.
>
> You are always drinking it. Those are just dissolved minerals. Mostly they are either ok or even good for you. But there's a lot more in the water these days that we can't get rid of without expensive methods.
>
> Those contaminants don't necessarily precipitate out in the boiling water.
>

And they are found in bottled water in a similar amount.
--
Uwe Bonnes b...@elektron.ikp.physik.tu-darmstadt.de

Institut fuer Kernphysik Schlossgartenstrasse 9 64289 Darmstadt
--------- Tel. 06151 1623569 ------- Fax. 06151 1623305 ---------

PCCSF Sanctuary

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Aug 19, 2020, 11:03:14 PM8/19/20

to

Found this thread because I'm trying to find the correct part number but you all have it all wrong.

There is a one way check valve that is not working. It's a little ball bearing sitting on an o-ring, It may even be a nylon ball.. I think in the manual its the blue tube but I can't find the correct image. I know this because My first two units, this failed in this way first, then the tank started to leak after I had replaced this little valve which required me replacing the whole unit. My second unit started sputtering and before I had a chance to replace the valve, I had a PGE event that took the heating element out. Insurance replaced the tank so I never bothered researching. Now my more recent unit is sputtering.

IIRC the oring eventually