Vaillant VCW 242/282 Heat Exchanger Leaking

[NotTheRedWire!]

Hi

I have a Vaillant VCW 242/282 combi with a leaky DHW heat exchanger. I have read some of the other posts about this as it seems fairly common with the older Duralite (I think its Duralite anyhow, the black plastic looking one) models.

I have bought the new "sardine can" upgrade which comes with all the bits and bobs but as I am a novice really I need a little advice before I get started.

1. I think I need to change the disc in the diverter valve as I have TRVs throughout the system. Is this a tricky procedure?

2. I have seen comments about cutting a link on the pcb on hybrid models but how can I tell if I have this model and if so, what link?

This may seem a little trivial to most i know, but be gentle!!!

Thanks in advance!!

 

[Agile]

As these boilers are getting pretty long in the tooth now I am surprised that anyone is still fitting this conversion.

I did one about five years ago for a ( low ) fixed price but it took longer than expected and I decided that I would think three times before doing another.

We still have a kit in stock somewhere but its probably going to stay there!

All I can advise is take care and allow plenty of time.

Tony

 

[NotTheRedWire!]

Thanks for getting back to me Tony, much appreciated. The main reason I am fiddling with this is that the boiler has only had about 4 years of use. It was sitting idle for donkeys years and then installed so its a fairly new old one if that makes any sense.

Any ideas on identifying the hybrid model or the disc in the diverter valve?

 

[Gasguru]

Always replace the auto air vent at the back.

Re-charge the expansion vessel - valve lower left.

Refurb the water section while you're at it.

Refurb the diverter since it has to come apart.

Remove and clean out all the control tubes (and banjo restrictor).

You may need to replace/refurb the servo valve - sometimes they play up.

Hybrids have HY printed on the diecast control box.

The new pipes often don't line up that well even on the genuine kits.

You need plenty of room on the LHS to tighten the plate exchanger fittings.



1/2 days work if it all goes well. and it will outlive most boilers installed today

But if your not mechanically minded forget it - this is old school German engineering - complex and not for the beginner.

 

[NotTheRedWire!]

Thanks, thats very uselful info.

I am planning on spending this Saturday on the repair so hopefully will have enough time, although time is not the issue. Its a love job you see......family eh!

Thanks again.

 

[garethr83]

any reason not to just dismantle the old plastic one by undoing the 16 screws and using new gaskets or sealing paste or similar?

thanks

 

[evsy01]

A non RGI should not be even taking the case off a boiler.

 

[Agile]

There is no real reason why a DIYer should not replace the plastic HE.

However, any expectation of stopping them leaking is a waste of time.

This boiler is now about 17 years old and the normal soluytion would be to replace it.

I have only fitted one conversion kit and that took me 2.25 hours and was not very enjoyable. Luckily I have not needed to do another one.

Tony

 

[garethr83]

well it's off and back on now so not much I can do about it.

the leak is only a small one which progressively got worse to around 4-5tsps a day. I can live with it to save £120 being asked for the new kit but as it is in the kitchen an directly above the worktop join sometimes there is a bit of swelling to be seen. Think I'll need some worktop sealant!

 

[Bunnyman]

Ok mate first ucant mend the plastic ht exch get the kit from abcot not the vailant one it sits sideways on it's cheaper an only takes a hour to fit. I have fitted dozens no problem with availability don't do the disc in divertor it's not necessary

Untitled

• Bunnyman
• 26 Mar 2010
• 499

 

[garethr83]

is this the part you speak of?
http://www.abcotuk.co.uk/Product.aspx?ProductId=P216&catid=C2

 

[Bunnyman]

thats the one the trick is fit the pipes to the heat exch then remove the old one and offer new one up and connect up..it is easy as long as u got left hand clearence