Main combi E30 Eco bolier

12 Feb 2013
Reaction score
United Kingdom
Hi all,
I am still losing pressure on my boiler and find that every morning the pressure is down to zero.
I have tried the following after a reply was posted:

Try turning off boiler, pressurise system to 2 Bar, and close the isolation valves where the flow and return pipes (the bigger pipes left and right side) go into bottom of boiler. Leave the boiler overnight.

When you return to boiler, if pressure has dropped, then fault is with boiler. If when you open the valves, the pressure then drops, the leak is somewhere on the system.

The answer to this is YES the pressure drops over night when the valves are turned off. Where is the water going then?

Please someone advise........ :(
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Don't quite get your humour here, the water aint on the worktop and after tying bags on the pipes outside it aint going out there either.
Any sensible answers would be appreciated.

Best regards.
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Check if the white plastic pipe if water comes out when boiler been off for a while then as above main heat ex gone thats what u get for buying cheap
Thanks guys, You say the main heat exchanger has gone, Am I right in saying that this is different to the heat plate exchanger?
Also where does the water go?

Both of you say to buy a decent boiler and not a cheap one ( it was in when we moved in) What is the best make to buy?


ps thanks guys for replying and advising
It will go out of the condensate pipe (plastic) it is different to the plate heat ex, you will hear of lots of boilers which are 'best' on here i like vaillants but im sure u will get replys saying worcester andintergas, just stay away from ibeal and anything from b&q
As Baz said.

Its the gas to water heat exchanger and not worth the cost of replacing the part alone on that boiler.

I would suggest the previous owner had to get a new boiler fitted quick because of the sale and got that thrown as quick as possible.

My preference for new boilers goes:


Atags are big brutes though.
Toe knee it does sound like the main heat exchanger has got a pin hole causing the water to leak out of the heat exch down the condense pipe!
Your best option is to take out a fixed price repair with the manafacturers covering all parts and giving you a years warranty! IMO the boiler is a very reliable one and you have been unfortunate! I have visited lots of these and only had to change the main heat exch once in the 2 to 3 years they have been made! ;)
Thanks to all that have replied to my dilema, I think maybe a call to British Gas and get them to do a "one off" repair.
What you reckon???????
If its the later type with a Gianonni style heat exchanger then the list price of these will be about £400 so a fixed price repair by the manufacturers will be a cheaper option.

If its the type with a recouperator then I would expect these are only about £90 so any engineer could probably do it for the same or less than the makers fixed repair price which is probably about £200-£300.


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