Any ideas please?
I have a Baxi solo boiler about 8 years old and the ch and dhw are controlled by 2-port motorised valves operated by the room and tank stats respectively. (fully pumped system)
Everything is fine with the ch but whenever the dhw valve closes there is an almighty single bang.
If the ch valve is open at the time then there is no problem and if I jam the valve open with the manual control lever there no problem when the tank stat shuts the boiler off.
I've bled the system more times than I can remember and drained and refilled the system twice but no success. Everything used to work fine so the 2 port dhw valve cannot be fitted backwards even though that would seem to be the obvious answer.
The pump is fitted to the return side of the boiler rather than the flow but once again it's been like that for years with no problems.
I have a Baxi solo boiler about 8 years old and the ch and dhw are controlled by 2-port motorised valves operated by the room and tank stats respectively. (fully pumped system)
Everything is fine with the ch but whenever the dhw valve closes there is an almighty single bang.
If the ch valve is open at the time then there is no problem and if I jam the valve open with the manual control lever there no problem when the tank stat shuts the boiler off.
I've bled the system more times than I can remember and drained and refilled the system twice but no success. Everything used to work fine so the 2 port dhw valve cannot be fitted backwards even though that would seem to be the obvious answer.
The pump is fitted to the return side of the boiler rather than the flow but once again it's been like that for years with no problems.