Boiler quandary

[agardner09]

We have an elderly Vaillant Turbo max 242E which has been serviced, etc but during the last 3 months has increasingly been "locking out" when we try to use it.
The engineer who has serviced it for the last 3 years has so far replaced the mother board (including the ignition mechanism) and the air pressure switch to no avail. He is now proposing to replace the gas valve. A second engineer whose opinion we asked said that he would not have replaced any of those components.
Our quandary is - do we stick with the first who at times seems unsure or do we risk someone new.
We are running out of arms and legs and winter is looming. Anyone got any helpful advice?

[The Builder]

You don't say exactly how old the boiler is, but there comes a time to stop throwing money at it!
Easy to say, I know. So, for now, I'd be inclined to give Guy B a chance this time

[terence7556]

do not use the first guy again, unless it is to ask for your money back.try the second chap but why not ask the second guy to fix it on a no fix, no pay basis.why should you keep subsidising part changing guys that do not appear to fault find on a logical basis.a PCB and gas valve plus fitting is not cheap
is the boiler showing any fault codes?

[agardner09]

Thanks for your contributions. The boiler is around 16 years old we believe, it was already in the house when we arrived. I understand lifespan is about 20 years so this one is probably on borrowed time.
As to fault codes this one hasn't even got a display to provide such luxuries, definitely prehistoric I'm afraid.
We have already considered a new one but an updated similar model (with minimum installation costs) would cost around £1800. A different (simpler?) one would need more installation and up goes the cost so we're back to an arm and a leg. We can't win!

[AlBags]

Have the pressure switch hoses been checked for cracks/leakage?
I just had an issue like that on a Baxi. Hose was splitting and causing gas valve to cycle.

[agardner09]

Thanks albags. We notice it is more likely to lock out when it is cold, if we can get it to warm up it will keep on lighting, could that be linked to split hoses ? Incidentally if a hose is cracked/split isn't there a danger of explosion!?

[AlBags]

Anybody's guess. Pretty easy to check tho. They are usually replaced by silicone tube (off the roll from local heating supplier)
Has the burner assy been properly removed and all the nozzle holes and jumper tracks been cleaned of scale?

[gucciman]

you could try calling out vaillant themselves to take a look at it, they have a fixed price repair charge that includes all parts and labour, if they can't fix it no-one can.
you could also try british gas, they also have a fixed price repair charge and if they don't fix it they don't charge, beware tho they WILL try to talk you into a new boiler !