Vaillant DHW heat exchanger conversion kit ??

[Mike1300]

Hi there all,
This is my first post and hopefully someone can help me.
I have a vaillant VCW GB240H combi boiler which has the usual fault with the plastic DHW heat exchanger (leaking).

I have the conversion kit to install my problem is that i purchaced this kit about 2 years ago but never got around to installing it as the leak has never got any worse and i have lost the fitting instructions.
I am okay with all the pipe connections as this looks like they will only fit one way, but i seem to remember something has to be done to the diverter valve and circut board but what ?

Also i have a replacement water section to fit at the same time and i was wondering if anybody can tell me what to do with the copper microbore pipe which i think goes to the expansion vessel as there is no connection for this on the newer version of water section (do i blank it off or leave it open)

 

[ChrisR]

Jeez fellah you're a sucker for punishment! Can only suggest you contact Vaillant for instructions. Yes there are some changes you'd have to make, a bit much for a forum answer - you'd be better off with full info.

 

[Slugbabydotcom]

Also i have a replacement water section to fit at the same time and i was wondering if anybody can tell me what to do with the copper microbore pipe which i think goes to the expansion vessel as there is no connection for this on the newer version of water section (do i blank it off or leave it open)

Its a while since I did one but as I recall there is a spare pipe which you can often just leave off.
If it does go to the mini PV as you say and you are concerned then theres nothing to stop you adding one to the Cold Water pipework close to the boiler after any check valve. They are available from BES Ltd online.
Generally you are advised to fit one if theres a check valve , water meter or shower in your cold /hot water pipework.[/code]

 

[mickyg]

don't worry about the mini ev. Its been designed out.
I might have some pics somewhere to help you out. Its quite an easy job tbh.

edit..here you are. This might be of some help...

Untitled

• mickyg
• 2 Jan 2010
• 3

 

[Mike1300]

Thanks guys for all your info regarding my problem.

Yesterday i replaced just the water section which has given me the the best hot water at the taps for ages, The temp adjustment valve had been jammed !!

Any way i still need to get the info on the diverter valve and circuit board mods before changing the heat exchanger, I have been told that the circuit board mod is only required if i have a hybrid control system, (How do i tell what mine is ? )

My system is 17 years old whats your opinions on replacement of a boiler this old ? I am very impressed with the service this boiler has given me over this time the other faults i have had is one diaphragm and one pilot thermocouple, so i do not really want to replace it yet as it seems like a well made and reliable boiler (ok as long as i can get spares for it)

Thanks again and happy new year to you all..

(I also have another problem with my vaillant VC112EH THERMOcompact ! please see my new post)

 

[mickyg]

If your happy with the performance then I would suggest keeping it. Pretty much all parts are still available and the boiler is capable of 25yrs of service.
As for the modification I'll have a check somewhere for instructions, but tbh unless you live in a really hard water area I wouldn't be that worried. Basically the water can get very hot, and the mod just tones it down to prevent scaling and scaulding.

in regards to hybrid/non-hybrid, pull of the thermostat knob, if the spindle is white plastic its a Hybrid model, if its metal its non-hybrid.