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Accurate refrigerator thermometer?

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KenK

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Dec 9, 2013, 11:47:33 AM12/9/13
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The past week my Kenmore refrigerator freezer has been running about 15
over 0. It used to be 0 or a bit less on the Walmart freezer thermo. I
tried another Walmart thermo that measures both refrig and freezer. Same
reading. Called extended warranty service guy. His (expensive?) thermo
read -5. He says freezer ok, my thermos bad. I had no grounds to argue
with him about it.

So my question is, where can I get an accurate thermo a service guy will
believe? Brand name? Source? Service guy says to buy from refig supplies
co - he also says the only one in my city only sells to dealers, service
guys, etc.

I also found out a previous service guy was wrong, my refrig does have
cooling coils. They are in back at bottom-rear (not under) of refrig. He
and I tried to pull refrig away from wall in it's little walled-off area
but were unsuccessful. Any suggestions on how I (79 yrs old) can move it
out to get at coils to clean them? Service guy suggested a leaf blower
blowing under frig - says it will clear off rear coils. ???

TIA


--
"Where there's smoke there's toast!" Anon





NotMe

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Dec 9, 2013, 12:30:47 PM12/9/13
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"KenK" <inv...@invalid.com> wrote in message
news:XnsA29163A04C...@130.133.4.11...
Try to find a lab thermoter. High school would do.


John Keiser

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Dec 9, 2013, 1:29:17 PM12/9/13
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An IR Thermometer gives instant results and can be used for many other uses
from catalytic converters to bad capacitors in a PC or TV. This was very
handy I when I needed to test for a bad defrost heater. Often available for
less than $20.


"KenK" <inv...@invalid.com> wrote in message
news:XnsA29163A04C...@130.133.4.11...

David L. Martel

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Dec 9, 2013, 1:46:48 PM12/9/13
to
Ken,

freezer has been running about 15
> over 0. It used to be 0 or a bit less on the Walmart freezer thermo.
> Called extended warranty service guy. His (expensive?) thermo
> read -5. He says freezer ok, my thermos bad. I had no grounds to argue
> with him about it.

It's really, really hard to believe that your thermometer suddenly failed
unless you whacked it. Yours reads 15 deg and his reads -5? That's 20 deg.
Something is most strange.
Take your thermometer out of the fridge and park it near a room thermometer
for half an hour. Is it 20 deg off?
Any cheap fridge/freezor thermometer should be NSF intl certified. That
means it's food safe and fairly accurate.

> So my question is, where can I get an accurate thermo a service guy will
> believe? Brand name? Source? Service guy says to buy from refig supplies
> co - he also says the only one in my city only sells to dealers, service
> guys, etc.

See above.

> I also found out a previous service guy was wrong, my refrig does have
> cooling coils. They are in back at bottom-rear (not under) of refrig. He
> and I tried to pull refrig away from wall in it's little walled-off area
> but were unsuccessful. Any suggestions on how I (79 yrs old) can move it
> out to get at coils to clean them? Service guy suggested a leaf blower
> blowing under frig - says it will clear off rear coils. ???

Ok, let's move the fridge. It's in an alcove and is glued down by years
of kitchen crud. Turn off the fridge using the temp control inside the
fridge. With the fridge door open look for and remove the bottom trim panel,
often look like vents. With the trim off and the fridge door closed you
should see the 2 front supports they should look like big bolts with rubber
feet. Get a pry bar and a fulcrum. Find a spot near a foot and on the
metal frame of the fridge. Pry there. We want to lift the fridge. Now do the
other foot. This should "unglue" the front feet.
Now carefully push the top of the fridge into the alcove. Then out. We
want to rock the fridge to free up the 2 back feet. When all of the feet are
free you should be able to rock the fridge from side to side and "walk" it
out of the alcove.
Now, unplug the fridge and vacuum the coils under and in back of the
fridge. Get a mop and swab out the alcove floor.
Plug the fridge back in. Walk the fridge back into the alcove. Open the
door and reattach the bottom trim panel. Set the temp control and close the
door.

Dave M.


Ralph Mowery

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Dec 9, 2013, 2:17:53 PM12/9/13
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"KenK" <inv...@invalid.com> wrote in message
news:XnsA29163A04C...@130.133.4.11...
> The past week my Kenmore refrigerator freezer has been running about 15
> over 0. It used to be 0 or a bit less on the Walmart freezer thermo. I
> tried another Walmart thermo that measures both refrig and freezer. Same
> reading. Called extended warranty service guy. His (expensive?) thermo
> read -5. He says freezer ok, my thermos bad. I had no grounds to argue
> with him about it.
>
>

He may have been reading the C scale instead of the F scale. the -5 C is
about 23 F.

To check the thermometer you can get a glass and put some ice and water in
it. Stir it for a while and put in the thermometer. It should show 32 deg
F or 0 deg C. Just don't have the thermometer on the ice ore side of the
glass, but in the water.

If your old thermometer changed that much and another one agrees with it,
looks like the service man may be wrong. Next time get him to try the ice
water test.



Oren

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Dec 9, 2013, 2:52:19 PM12/9/13
to
On Mon, 9 Dec 2013 08:29:17 -1000, "John Keiser"
<john.k...@hawaiiantel.net> wrote:

>An IR Thermometer gives instant results and can be used for many other uses
>from catalytic converters to bad capacitors in a PC or TV. This was very
>handy I when I needed to test for a bad defrost heater. Often available for
>less than $20.

Just how accurate is $20 IR thermometer? Is has to be off by some +/-
yet more costly ones would be more accurate.

(same with laser levels)

Stormin Mormon

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Dec 9, 2013, 3:42:12 PM12/9/13
to
On 12/9/2013 1:29 PM, John Keiser wrote:
> An IR Thermometer gives instant results and can be used for many other uses
> from catalytic converters to bad capacitors in a PC or TV. This was very
> handy I when I needed to test for a bad defrost heater. Often available for
> less than $20.
>

Those point and read units are not accurate
on shiny metal. Need to read the temp of the
items in the freezer. Ice cubes, boxes of
food, etc.


--
.
Christopher A. Young
Learn about Jesus
www.lds.org
.

Stormin Mormon

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Dec 9, 2013, 3:43:25 PM12/9/13
to
On 12/9/2013 2:52 PM, Oren wrote:
> Just how accurate is $20 IR thermometer? Is has to be off by some +/-
> yet more costly ones would be more accurate.
>
> (same with laser levels)
>

I've seen at the big box stores, indoor
outdoor thermometer. some have a probe at
the end of a wire. You can stick the probe
in the freezer, and read it with the door
closed.

Bob F

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Dec 9, 2013, 4:01:58 PM12/9/13
to
Fill a glass with ice cubes. Top it off with water. Let it sit for a few
minutes, maybe stirring a couple times. Stick your thermometer in it. It should
read about 32F. If not, it's off.


Erik

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Dec 9, 2013, 4:07:27 PM12/9/13
to
Agreed.

Also, refrigerator & freezer temps continuously 'bounce' up and down all
the time caused compressor cycling, defrost cycles, and door opening events.

It's the 'average' temperature that's important.

For the refrigerator side, put your thermometer in a glass of water; one
where you can read it while still submerged. It's amazing how quickly
some thermometers can react to room temperature air if pulled out for
reading. Give it a day to normalize, then take and average multiple
readings over a few days.

Same dance with the freezer, but sandwich the thermometer between
something like bags of frozen vegetables, and read with the sensing bulb
still sandwiched.

For the record, I've had pretty good luck with those bi-metallic analog
refrigerator/freezer thermometers. Their 'capsule' isn't vented, so they
retain an accurate reading for a short period. They can also be
quickly/easily read in place... and I'm now in the habit of checking
them every door opening

I've heard the best temps for maximizing food storage time with minimal
energy use is 40�F in the refrigerator, and 0�F for the freezer.

As I recall, most if not all of the above is in my refrigerator owners
manual... check yours, it's likely there as well.

Good luck!

Erik



Fred McKenzie

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Dec 9, 2013, 5:33:24 PM12/9/13
to
In article <HXppu.401229$5W.3...@fx11.iad>,
Stormin Mormon <cayo...@hotmail.com> wrote:

> On 12/9/2013 2:52 PM, Oren wrote:
> > Just how accurate is $20 IR thermometer? Is has to be off by some +/-
> > yet more costly ones would be more accurate.
> >
> > (same with laser levels)
> >
>
> I've seen at the big box stores, indoor
> outdoor thermometer. some have a probe at
> the end of a wire. You can stick the probe
> in the freezer, and read it with the door
> closed.

I agree that it would be a good idea to check a thermometer against ice
water. The probe type mentioned above, would definitely survive the
test.

I use a Radio Shack wireless indoor-outdoor thermometer, catalog number
6300333. It is compatible with remotes from their older model 63-1030.
You would need to find another way to test the remote for accuracy,
since they are not meant to operate under water!

This type of thermometer can be set to read remote units on three
different channels. If you buy two units, you could put one remote in
the freezer and one in the refrigerator section on different channels.
I currently have remotes in two areas of my refrigerator to investigate
why my milk was spoiling.

Granted they are not laboratory precision. They read out to the nearest
tenth of a degree, but I found several remotes to have about a one
degree spread. But being digital, it might impress the service guy!

Fred

John Keiser

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Dec 9, 2013, 6:46:26 PM12/9/13
to
Like anything else, one must shop carefully on eBay or Amazon.
My unit seems very accurate when measured against ice and boiling water. I
haven't thought if a standard for high temperature catalytic converters yet.
:)


"Oren" <Or...@127.0.0.1> wrote in message
news:ml7ca91jkokmja66r...@4ax.com...

mike

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Dec 9, 2013, 7:26:55 PM12/9/13
to
IR thermometers are notoriously inaccurate.
They measure radiation, not temperature.
Different surfaces have different emissivities. They
give different readings for the same temperature.
More expensive ones have adjustments for emissivity,
you just have to know the exact number for that exact
surface...

Another little-appreciated fact is that cheap ones have
a wide
field of view. Unless the item fills the field of view,
you can't count on the numbers.

If you wanna measure the temperature in the fridge for cheap,
go get a liquid thermometer. Those graduated on the glass
are likely more accurate than those that can move
against a calibrated holder.


gregz

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Dec 9, 2013, 9:49:09 PM12/9/13
to
Looks like you tried two thermometers good show. Where it was placed and
time of day might alter readings.

If you want to be safe, use one thermometer that measures closely to one or
two others. I also often use an IR thermometer to verify another reading.
Thermometers can drift off, or be off. Just know what Is what.

I don't have access to it anymore, but I used to also use a data logger to
track 24 hours.

Greg

gregz

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Dec 9, 2013, 10:00:46 PM12/9/13
to
Not sure what that is, but when I measured lab equipment I had access to a
few of my choice instruments. Radio shack $15 thermistor probe, fluke and
triplet thermocouple probes. Fluke IR thermometer, as well as HF near field
IR thermometer. Large mercury thermometer, I only used as a comparison.

Sometimes probes have to be right on top of each other, and stabilized, to
get the same readings. Air flows can be deceiving. Even taking a reading of
a beaker of water, needs high circulation to get equal readings. There is
normally a high temperature differential of a still beaker of water.

Greg

garyr

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Dec 9, 2013, 10:38:12 PM12/9/13
to

"KenK" <inv...@invalid.com> wrote in message
news:XnsA29163A04C...@130.133.4.11...
> The past week my Kenmore refrigerator freezer has been running about 15
> over 0. It used to be 0 or a bit less on the Walmart freezer thermo. I
> tried another Walmart thermo that measures both refrig and freezer. Same
> reading. Called extended warranty service guy. His (expensive?) thermo
> read -5. He says freezer ok, my thermos bad. I had no grounds to argue
> with him about it.
>
> So my question is, where can I get an accurate thermo a service guy will
> believe? Brand name? Source? Service guy says to buy from refig supplies
> co - he also says the only one in my city only sells to dealers, service
> guys, etc.
>
> I also found out a previous service guy was wrong, my refrig does have
> cooling coils. They are in back at bottom-rear (not under) of refrig. He
> and I tried to pull refrig away from wall in it's little walled-off area
> but were unsuccessful. Any suggestions on how I (79 yrs old) can move it
> out to get at coils to clean them?


Rent an air sled. Easy as pie.

RMD

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Dec 10, 2013, 12:43:08 AM12/10/13
to
I've found mercury thermometers are all over the place at freezer
temperatures. 10C errors are easy to have. I put the unkown
thermometer in a known good freezer running at -18C and mark the
mercury level with a marker pen, then use it to check my unknown
freezer temperature.

Even allegedly accurate thermocouple thermometers on a digital
multimeter can be all over the place at -18C.

Having said that I do have some cheap mercury thermometers that do
actually read correctly at -18C. Otoh I have two quite expensive
refrigerator mercury thermometers that read fine at refrigerator
temperatures, but are both quite wrong at freezer temperatures.

My experience is that it isn't easy to read freezer temperatures
accurately. Even allergedly identical mercury thermometers can differ
by 5C. (I've tried 30 or 40 mercury thermometers out btw.) Ditto
bimetal strip thermometers.

Yeah, I know. It surprised me too!

Btw it makes quite a difference to freezer running cost if it is
running too cold. 10C too cold is the same as making it 10C hotter
ambient temperature. It can boost the daily running cost by 50%.

Ross

Ross

Ross

KenK

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Dec 11, 2013, 12:56:01 PM12/11/13
to
"garyr" <ga...@fidalgo.net> wrote in
news:l862bn$3rl$1...@speranza.aioe.org:

>
> "KenK" <inv...@invalid.com> wrote in message
> news:XnsA29163A04C...@130.133.4.11...
>> The past week my Kenmore refrigerator freezer has been running about
>> 15 over 0. It used to be 0 or a bit less on the Walmart freezer
>> thermo. I tried another Walmart thermo that measures both refrig and
>> freezer. Same reading. Called extended warranty service guy. His
>> (expensive?) thermo read -5. He says freezer ok, my thermos bad. I
>> had no grounds to argue with him about it.
>>
>> So my question is, where can I get an accurate thermo a service guy
>> will believe? Brand name? Source? Service guy says to buy from refig
>> supplies co - he also says the only one in my city only sells to
>> dealers, service guys, etc.
>>
>> I also found out a previous service guy was wrong, my refrig does
>> have cooling coils. They are in back at bottom-rear (not under) of
>> refrig. He and I tried to pull refrig away from wall in it's little
>> walled-off area but were unsuccessful. Any suggestions on how I (79
>> yrs old) can move it out to get at coils to clean them?
>
>
> Rent an air sled. Easy as pie.


What's an air sled? Sounds better than my little hand truck.

Bob F

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Dec 11, 2013, 2:02:52 PM12/11/13
to
Fred McKenzie wrote:
> I use a Radio Shack wireless indoor-outdoor thermometer, catalog
> number 6300333. It is compatible with remotes from their older model
> 63-1030. You would need to find another way to test the remote for
> accuracy, since they are not meant to operate under water!
>
> This type of thermometer can be set to read remote units on three
> different channels. If you buy two units, you could put one remote in
> the freezer and one in the refrigerator section on different channels.
> I currently have remotes in two areas of my refrigerator to
> investigate why my milk was spoiling.
>

And they will transmit through a freezer's grounded metal shell?


Irreverent Maximus

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Dec 11, 2013, 5:18:28 PM12/11/13
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"Bob F" <bobn...@gmail.com> wrote in message news:l8act8$g5h$1...@dont-email.me...
Are the doors grounded?

Bob F

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Dec 11, 2013, 7:35:33 PM12/11/13
to
The hinges on mine have metal to metal contact. Any reason they wouldn't be?


k...@attt.bizz

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Dec 11, 2013, 9:37:08 PM12/11/13
to
On Wed, 11 Dec 2013 16:35:33 -0800, "Bob F" <bobn...@gmail.com>
wrote:
You're not an engineer, are you? Nah, you're too stupid.

gregz

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Dec 11, 2013, 9:46:14 PM12/11/13
to
In order for it to be a shield, the door would have to make electrical
contact all the way around. Grounded hinge only, is an antenna.

Greg

Irreverent Maximus

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Dec 11, 2013, 10:23:54 PM12/11/13
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"gregz" <ze...@comcast.net> wrote in message news:710102429408509090.27...@news.eternal-september.org...
Bingo!

Fred McKenzie

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Dec 13, 2013, 6:23:44 PM12/13/13
to
In article <l8act8$g5h$1...@dont-email.me>, "Bob F" <bobn...@gmail.com>
wrote:
I did not think of that, but it has not been a problem with my
refrigerator with top freezer. I suppose some may have better shielding
than others.

Fred

Erik

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Dec 13, 2013, 9:48:10 PM12/13/13
to
Those thick plastic/rubber refrigerator door seals leak RF like a sieve.
There are typically other cavity breaches only plugged with plastic
and/or insulation.

Refrigerators make horrible Faraday cages...

http://en.wikipedia.org/wiki/Faraday_cage

A little off topic, but on the subject of Faraday cages... A while back
I stumbled across some law enforcement training videos on the use of
portable 'Faraday Bags'... to prevent thugs (and their family & friends)
from remotely tampering with seized smart phones and other devices.
They made it sound like most every cop car on the planet now stock's an
assortment of the things. There are some limitations and gotchas
involved... more here:

http://en.wikipedia.org/wiki/Mobile_device_forensics

Erik

bengian...@gmail.com

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Mar 16, 2016, 10:54:36 AM3/16/16
to
Kenworth told us on our new trucks refrigerator and freezer were just fine with temp when we took it to Desmoines dealer where it was bought, when both freezer and fridge were running about 20 degree higher than their readings. We had spoiled food and freezer didn't freeze. They were suppose 2 fix 4 things and only fixed 1! Why would u buy another Truck from them when they don't fix what's wrong with it when it's brand new! Plus their customer service is lousy!

Tekkie®

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Mar 16, 2016, 4:52:33 PM3/16/16
to
bengian...@gmail.com posted for all of us...


>
> Kenworth told us on our new trucks refrigerator and freezer were just fine with temp when we took it to Desmoines dealer where it was bought, when both freezer and fridge were running about 20 degree higher than their readings. We had spoiled food and freezer didn't freeze. They were suppose 2 fix 4 things and only fixed 1! Why would u buy another Truck from them when they don't fix what's wrong with it when it's brand new! Plus their customer
service is lousy!

Dats nize

--
Tekkie
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