Vaillant VCW 242E Reluctant hot water
Luke
My friend's Vaillant VCW 242E has been getting more and more reluctant
to produce hot water in the last few months. By "reluctant" I mean
that the hot tap has to be opened wider and wider before the burner
fires and hot water issues forth. This has got so bad lately that it
is impossible to use the shower unless the boiler is first given a
prod by opening the hot water tap in the kitchen full blast.
We have taken the front off the boiler and observed that the command
to fire the burner is controlled by firstly a microswitch and then a
gas valve(?), both of which are operated by a pushrod which is
connected to the incoming cold water supply. It seems that whatever
controls the pushrod is no longer giving it the required "ooomph" at
low to medium flow rates.
We have hypothersised it is the diaphragm at fault here - would we be
correct? Looking at the availability of spare parts, I have found
http://www.uk-plumbing.com/vaillant-spares-vaillant-diaphragms-c-938_852_1244.html
Which seems to list a number of different diaphragm options for this
boiler.
My questions are:
1. Are we right in suspecting the diaphragm is at fault here?
2. If so, which of the options on the page referenced above should we
choose?
3. Will we need the service manual in order to fix the problem or
should it be pretty obvious disassembly-wise to remove and replace?
Thanks in advance
Luke
geoff
<d0cdf552-348e-4a12...@r40g2000yqn.googlegroups.com>,
Luke <wing...@fsmail.net> writes
>Hi,
>My friend's Vaillant VCW 242E has been getting more and more reluctant
>to produce hot water in the last few months. By "reluctant" I mean
>that the hot tap has to be opened wider and wider before the burner
>fires and hot water issues forth. This has got so bad lately that it
>is impossible to use the shower unless the boiler is first given a
>prod by opening the hot water tap in the kitchen full blast.
>
>We have taken the front off the boiler and observed that the command
>to fire the burner is controlled by firstly a microswitch and then a
>gas valve(?), both of which are operated by a pushrod which is
>connected to the incoming cold water supply. It seems that whatever
>controls the pushrod is no longer giving it the required "ooomph" at
>low to medium flow rates.
>
>We have hypothersised it is the diaphragm at fault here - would we be
>correct? Looking at the availability of spare parts, I have found
>
>http://www.uk-plumbing.com/vaillant-spares-vaillant-diaphragms-c-938_852
>_1244.html
>
>Which seems to list a number of different diaphragm options for this
>boiler.
>
>My questions are:
>
>1. Are we right in suspecting the diaphragm is at fault here?
Almost certainly the diverter valve and yes, probably the diaphragm
>2. If so, which of the options on the page referenced above should we
>choose?
You'll see that some of them are kits and some of them diaphragms - a
complete mess like most 242 parts
Personally, armed with the exact model and serial number (e.g. is it a
242E or 242EH?) I would email them and ask them which one (I would buy
the diaphragm kit as should include the seals etc. It's not something
you want to repeat next year because a seal has gone or something), then
the responsibility lies with them to get it right
>3. Will we need the service manual in order to fix the problem or
>should it be pretty obvious disassembly-wise to remove and replace?
>
No - the manual only goes as far as replacement of the diverter valve
IIRC
SO ...
You want to repair your diverter valve
Make drawings and photos at every stage. I can't emphasise how important
this is - there are so many things that could go one way or an other
Do it in one sitting then you have less time to forget
its much easier once you've done a few
Other than that, it's straightforward
Isolate the boiler, drain down, remove the diverter valve, mend and
replace
--
geoff
Thomas Prufer
>>My questions are:
>>
>>1. Are we right in suspecting the diaphragm is at fault here?
>
>Almost certainly the diverter valve and yes, probably the diaphragm
Is there a small chance that lubricating it would help?
I have a 240, and the diverter valve pin that actuates the microswitch started
to stick. A drop of light lubricant (no, not WD-40!) sorted it, now going on for
a few years.
>Personally, armed with the exact model and serial number (e.g. is it a
>242E or 242EH?) I would email them and ask them which one (I would buy
>the diaphragm kit as should include the seals etc. It's not something
>you want to repeat next year because a seal has gone or something), then
>the responsibility lies with them to get it right
>
>
>>3. Will we need the service manual in order to fix the problem or
>>should it be pretty obvious disassembly-wise to remove and replace?
>>
>
>No - the manual only goes as far as replacement of the diverter valve
>IIRC
>
>SO ...
>
>You want to repair your diverter valve
>
>Make drawings and photos at every stage. I can't emphasise how important
>this is - there are so many things that could go one way or an other
>
>Do it in one sitting then you have less time to forget
>
>its much easier once you've done a few
>
>Other than that, it's straightforward
>
>Isolate the boiler, drain down, remove the diverter valve, mend and
>replace
And you may need some stuff to descale the innards, depending on your water. And
gaskets for the stuff nearby. They will start to leak if disturbed when the
shops are closed...
geoff
<prufer...@mnet-online.de.invalid> writes
>On Wed, 2 Dec 2009 21:23:51 +0000, geoff <ra...@kateda.org> wrote:
>
>
>>>My questions are:
>>>
>>>1. Are we right in suspecting the diaphragm is at fault here?
>>
>>Almost certainly the diverter valve and yes, probably the diaphragm
>
>Is there a small chance that lubricating it would help?
>
>I have a 240, and the diverter valve pin that actuates the microswitch started
>to stick. A drop of light lubricant (no, not WD-40!) sorted it, now
>going on for
>a few years.
Usually, the diaphragm kit includes the pin, which does wear with use
If you must lubricate - silicone grease
>
>
>>Personally, armed with the exact model and serial number (e.g. is it a
>>242E or 242EH?) I would email them and ask them which one (I would buy
>>the diaphragm kit as should include the seals etc. It's not something
>>you want to repeat next year because a seal has gone or something), then
>>the responsibility lies with them to get it right
>>
>>
>>>3. Will we need the service manual in order to fix the problem or
>>>should it be pretty obvious disassembly-wise to remove and replace?
>>>
>>
>>No - the manual only goes as far as replacement of the diverter valve
>>IIRC
>>
>>SO ...
>>
>>You want to repair your diverter valve
>>
>>Make drawings and photos at every stage. I can't emphasise how important
>>this is - there are so many things that could go one way or an other
>>
>>Do it in one sitting then you have less time to forget
>>
>>its much easier once you've done a few
>>
>>Other than that, it's straightforward
>>
>>Isolate the boiler, drain down, remove the diverter valve, mend and
>>replace
>
>And you may need some stuff to descale the innards, depending on your
>water. And
>gaskets for the stuff nearby. They will start to leak if disturbed when the
>shops are closed...
--
geoff
Luke
>
> >On Wed, 2 Dec 2009 21:23:51 +0000, geoff <ra...@kateda.org> wrote:
>
> >>>My questions are:
>
> SNIP USEFUL ADVICE FROM GEOFF & THOMAS
>
>
> > - Show quoted text -
Thank you both for your replies. We had already lubricated the
diverter valve pin a month or so ago, admittedly not with silicon
grease but with 3-in-1. It seemed to have a temporary effect but the
problem remains.
We are going to buy the diaphragm kit as recommended by Geoff and
replace it. As suggested we will take photos and make copious notes
etc and should hopefully be okay. Will report back afterwards.
Thanks again
Luke
peter richards
over 5 years old and its easey [keep away from the gas side] also look at
the radiator again a simple job of replacement it could be fured up with
scale and you can get the part from the manafacturer also are you in a hard
water area ? That could be a furing up of the pipes, fit a cheap scale
inhibitor
Best wishes for hot water