Pump always on

[jep49]

Just replaced the trvs on possibly future son in laws house today. Turned it all off and pump continued to run, and not stop. He says it has always done that. Its a british gas programmer, made by invensys, model UP2. 2 ports, wiring centre,glowworm micron 40ff,system. Strange thing it , it is fully trv on all rads, with a bypass PIPEwith a gatevale on it. It has, and is working ok though. But as the boiler seems to have just a switched earth conection, do you think it is a programmer fault or a wiring centre fault that is keeping the pump on? i had to switch it off at the mains to stop it. He says as far as he can remember it has been on since new boiler was fitted 10 years ago, but now system is quiter he notices it more.

 

[Tipper]

Is there a motorised valve involved?

If so then it's probably the failure of the valve head which contains auxiliary switches which control the pump and boiler.

 

[jep49]

There are two valves on system, but i think i saw both of them moving when the system was switched about. Will have to rechech this . Is it likely the pump was wired to a permanent live wire in the wiring centre by mistake.

 

[Tipper]

My point is that when valves are installed in the system, the boiler and pump are usually wired through the auxiliary switches in the valve head using the permanent live via the auxiliary switches.

If one of these has failed then the boiler and pump will be on 24/7.

A new valve head will be probably required on one of the valves.

 

[jep49]

I see what you mean. The boiler itself didnt appear to be on with the pump.would that necesserily mean it wasnt the motorised valve. I will chech out furthur about the vaves to see what is happening.