Ehh? What are you on about? I’m trying to deter people from taking incorrect and expensive advice.
I did read it properly, you didn’t. You also said it wouldn’t be at the OP’s expense
Vaillant boiler losing pressure
- Thread starter Patrick_
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It doesn't explain how the boiler can fail on an F22 due to low pressure, then mysteriously top up its own pressure to be able to function again. Heat input causes pressure to rise, when it cools pressure reduces. The complaint seems to be that it is doing the precise opposite of that - despite the protests to the contrary.
What I believe has happened, the boiler pressure has dropped to 0.5 bar, on that model of pro once the pump kicks in (the 2nd component to be energised), the pressure goes up by 0.5 bar, so could have brought the heating on that way.
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A temperature rise in the property heats the water in the system which expands and raises system pressure enough to bring the boiler back on. Especially when ev is depleted.
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Then it is under Vaillant warranty so get them out, I agree probably an expansion problem, which they would say should be checked at every service, but as it isnt 12 months old yet, that is not a get out they can use, as @jeff the gasman says the expansion vessels on these are very poor
Guess again
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