Pump won't stop running

[Jonathan Myers]

Hi

First post!

I’m having an intermittent problem with our central heating. It’s a fully pumped system almost 30 years old. It has 3 motorised valves for hot water, downstairs CH and upstairs CH.

The problem is that when all the timers are turned off, the pump keeps running. The boiler isn’t firing. Just the pump is running. If I fiddle with the lever on the downstairs motorised valve I can sometimes get it to stop.

I don’t think any water is actually circulating around the system . So what I’d like to ask is, if all of the three motorised valves are closed and the pump is running, is this dangerous or going to cause any damage? Or is it safe to just let this continue? Thanks!

 

[king of pipes]

If you could post some pictures we will be able to help you , the pump should only run for 3 - 4min after a valve closes this is known as pump overun and removes the access heat from the boiler it needs the facility fitted in the pipework flow and return known as a automatic bypass to do this, if the pump runs continually it will eventually fail, you need a heating engineer to diagnose and repair the fault . regards kop

 

[Harvest Fields]

Also have you just moved in or been there years?

 

[Steve.H]

is the lead from the pump wired into a wiring centre or going straight to a socket? I’ve seen it before going straight to the socket and the pump has been running continuously.

 

[Harvest Fields]

is the lead from the pump wired into a wiring centre or going straight to a socket? I’ve seen it before going straight to the socket and the pump has been running continuously.

Bad practice mate. Should be wired in correctly

 

[Steve.H]

Bad practice mate. Should be wired in correctly

Yeah I agree just something I’d seen on old systems,and was wondering why Jonathan’s pump was running continuously !

 

[dan_the_plumber]

Sounds to me that it’s been wired incorrectly.
Pump may be getting its switch live direct from the programmer or room stat, rather than from auxiliary switch in motorised valve (grey & orange)

 

[SimonG]

Enquiring minds looking for an update to the supposed problem!

 

[Jonathan Myers]

Thanks for all the replies. We've been here since the house was built almost 30 years ago. I'm sure the problem is with the downstairs motorised valve - if I fiddle with the lever on that valve for long enough there is a little click and the pump turns off - but if I leave it alone the pump just runs continuously. Over the years we've had occasional problems with all three motorised valves sticking open and they've all been replaced once. But in the past the problem has been the boiler keeps running continuously and won't turn off with the clocks - this time the boiler isn't firing, it's just the pump that's running.

 

[king of pipes]

Sounds like you have found the fault get the compleate valve changed . kop