Good one by Dave Cooper posted 16 Feb 2020 at 6:55 PM
It's more violent than just a sound. The whole boiler shakes.
My combi has started shaking intermittently during the recent stormy weather almost as if air pressure is getting trapped in through the flue...
What would happen if it was fully open or closed?
Please let me know if you guys need more info
There is a valve connected between the outflow and return pipes just under my combi boiler. What is this for and should it be open or closed?
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