Vaillant VCW 242EH Boiler - No Hot Water

[VaillantHelp01]

Hi all,
thank you for taking the time to look at my 'post' & hopefully you may offer some ideas on how to rectify the problem?

The hot water has virtually stopped working however the C/Heating is still operating ok.
Generally the boiler is not firing up when the HW is called for, however the other day the boiler did fire & the water temperature was warm only.
The HW adjustment knob is seized in position & a replacement part (011299 supersedes 011267) is on site however the small microbore pipe is no longer required on the new part (any ideas, is it just capped off when new part is fitted?)
Seems like it may be an electrical issue? as the boiler should fire each time the HW is called for so i'm considering the following items;
Micro Switch (126233)
Diverter Valve (012684)
Vaillant engineers have been out a couple of times previously & adjusted 'something' allowing the HW to work for some time after the repair but never a satisfactory fix (last time around1 yr)
I would like to find the problem and replace the faulty part as generally this is a good old boiler which just needs a little tlc (well don't we all from time to time!)
Well if you have any ideas to locate the problem they will be much appreciated, thank you.
ps the boiler is located off site (mums house) so i would not be able to inspect there & then so please bear this in mind if you are kind enough to answer, thanks[/b]

 

[twgas]

Sounds like the div valve diaphragm needs replacing, the bits that were adjusted, were they the microswitch(es) near the bottom on the right?

 

[VaillantHelp01]

Hello Mick,

thanks for your reply

i'm not really sure as not there when the engineers carried out the works.
I've been drawn to the diverter valve ( just by looking up info on the internet) is it much easier to just change the diaphram or not too bad to change the whole valve?

Re the Water Valve - the existing unit has x5 outlets (x4 large & x1 microbore) however the replacement item only has x4 large outlets and the microbore is no longer required. Do you know what should happen with this pipe ? (checked with vaillant helpline & correct part has been supplied however no further information forthcoming)

thanks
Pat

 

[The831Bunny]

Hi Pat

Change the water section - the small 6mm tube to the domestic expansion vessel can be connected to the cold inlet on the valve after removing the plug and bending the tube down and round. It's not generally needed, so don't worry if you can't manage it. FYI it's there to absorb the expansion of hot water (very small) and to comply with water by laws concerning back flow and contamination. It only really comes into play if you have a non-return valve on your cold water main.

This appliance is getting on now, but is worth repairing. Have you not considered a local independent engineer who has knowledge of Vaillant appliances. There's lots to check and adjust on this model, and you could be at the start of a slippery slope of making rash decisions on replacing it when all you really need is knowledge from an experienced engineer.

Hope you get on ok

 

[VaillantHelp01]

Thank you Mr.Bunny,

i'm going to call vaillant on Monday & see if they can recommend a local engineer whom has training on the vcw boiler.
As you stated it appears to be quite complex therefore looking for an engineer with the relevant experience.

Many thanks for your reply

Pat

 

[Agile]

I would doubt that Vaillant will know more than 1% of all the competent engineers in the country if any! Why should they?

Better to find a competent local engineer and ask if he is familiar with your boiler.

Its nothing very special!

Tony

 

[VaillantHelp01]

Hi Tony

thanks for your reply.

Just thought vaillant have a training programme & may be able to point me in the right direction ?
i'm sure we've all watched 'Watchdog' (haha) so just a little sceptical thats all.
Well looks like hitting the phone tomorrow & see what happens ?

Cheers
Pat

 

[Phill Peck]

As tony suggested they are not hat difficult

But they do look a bit confusing compared with modern stuff

As said someone familiar with the boiler is what is needed, ill admit that I have had to put my hand up and ask for help when working on these

 

[Bunnyman]

Sorry mate Vaillant will be no help with this boiler, it was listed as obelete from April 2012. I still have dozens on my books an there a good unit. Google a local Vaillant specialist is ur best bet. Vaillant will recommend a new unit!