Bypass radiator always hot/ Boiler pump constantly on
Boiler: Potterton Promax 30 SL
S plan/ 1HW/1CH zone valve
Our bypass radiator by the HW tank is constantly permanently hot regardless of the radiator valve position. If I turn the valves off, it causes the boiler to go into overheat lockout.
I've checked and touched the boiler pump and that seems to be constantly on/vibrating.
I've noticed that our boiler also sometimes randomly fires up for a few seconds.
We have had our HW zone valve replaced not too long ago with a wiring mishap which was later rectified. My understanding is, if it was the zone valve issue again, wouldn't that also fire up the boiler and not just have the pump constantly running?
With both HW/CH controls off, what's causing the Bypass radiator to be permanently hot/pump to be constant?
2 Answers
GC Oil and Gas
0 Reviews
Probably siezed ch valve stem or one or both actuator micro switches stuck on causing a constant demand and ch. valve passing
8th Jul 2021
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Da contractors
0 Reviews
It shouldn't be hot if your programmer isn't calling for heat.
Some heating engineers will wire the pump permanently on but this isn't really practical id normally wire it to the hot water on function.
You could do with someone checking your central heat wiring
Some heating engineers will wire the pump permanently on but this isn't really practical id normally wire it to the hot water on function.
You could do with someone checking your central heat wiring
10th Nov 2021
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