Powermax 155x boiler - Cylinder gas leak?

21 Nov 2009
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United Kingdom

Can anyone give some advice...I have a service and maintenance plan for my boiler.

Last week we smelt gas coming from our powermax 155x (6yrs old) heating boiler, the engineer came out 2 days later and changed various burners then said the leak was somewhere in the cylinder and could not find it, he told us he had already gone over his alotted time and condemmed the boiler.

Can someone tell me if gas goes through the cylinder in this particular model and would this part/s still be available. My service plan allows upto £1500 on parts.

The service contractor has since given us a quote for a new boiler which I will have to pay as my insurance does not cover for replacement.
Any advice would be appreciated.
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I dont know of any boiler where gas goes through the cylinder! In plumbing and heating terms the cylinder is usually found in an airing cupboard and is actually the hot water tank, (containing water NOT gas!). It is known as a cylinder due to its shape!

It would be unlikely parts are not available for a boiler of this age, rather smells to me like a scam and they're trying to sell you a new boiler rather than correctly diagnosing the fault on the exisiting boiler and repairing it. If the engineer went over his allotted time then he should have scheduled another visit.

I strongly recommend you get them back, tell them you want the correct fault diagnosed and repaired. That is what you are paying your premiums for! If they still insist parts are unavailable then ask for the name of the part they claim is faulty and post back.
No not gas though burnt combustion fumes come out of the bottom. Call the company back and ask them to identify the faulty part and the reason it can't be repaired and advise you will be seeking a second opinion. The cylinder is obsolete by the way and it is possible for it to be so damaged as to condemn the boiler but I doubt it's the case here.
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I just scrapped one of these things. If its leaking gas then I'm assuming its been turned off? surely they must be able to locate it. Get them back to at least accurately tell you the problem.
When you say gas coming from boiler, can yoo smell natural gas or is it fumes / co alarm going off. Gas train on 155x isn't very big so any 'gas' leak should not be difficult to trace. Simple tightness test would tell engineer if leak is prior to or after appliance isolation point.
It sounds like you have a POC leak from engineers work.
There are two seals plus test point on boiler which can leak POC's that can be repaired.
Any leak on flue is normally not covered by Insurance policies as are leaks on gas carcass but this depends on your individual contract.
Thanks for all of the responses, The service/maintenance package is supplied through Domestic and General...

I have gone back to them and requested the part no. for the part that is faulty, they could not tell me and heat team who carried out the work on there behalf said the service engineer did not record the faulty part no. and was not in work this weekend. I will hopefully find this out tomorrow.
This boiler is a downward firing burn chamber........the cylinder is an integral part of the heating/fluing system. The baffles corrode as does the sump at the bottom. IF and only IF the leak (i doubt it's gas as it would be ignited) is say on the cylinder shoulders etc it would be beyond economical repair. As would corrossion of the baffle compartments etc. Burner and sump etc are still available as spares......however you may well be better reoplacing it anyway......it's trouble!

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