Continuous heating

[thebadleys]

The pump on my central heating continues to pump after the thermostat has switched off and no hot water has been used. I realise that the pump should "overrun" but mine just keeps running.

The thermostat is a wireless type and the receiver does not indicate a heat call when the pump is going.

Any ideas please

 

[Agile]

And the make and model of the boiler is........

 

[thebadleys]

Sorry the boiler is a Worcester Greenstar CDi Condensing with a Drayton Tempus 7 Electronic Programmer and a Salus Digital Radio Thermostat

 

[bengasman]

When and how did this change?

 

[simond]

This would the 30CDi conventional.

Most likely your motorised valve is stuck and the boiler is 'on' all the time.

Check the 'switched live' cable connection to the boiler. if it is on all the time (even with the tempus off) you have a stuck microswitch in the valve.

It is unusual for the Worcester PCB to play up.

 

[thebadleys]

It has been a intermittent problem for a few months, the boiler was installed 18 months ago and the installer has said he cannot fault it but it still happens.

Perhaps the motorised valve sticking intermitantley could be the reason, can it be repaired or does it need replacing?

 

[bengasman]

Did it suddenly start misbehaving? Are you sure it did not run all the time right after the boiler was installed? Has anything happened or been changed?

 

[thebadleys]

We really only noticed the problem this spring when we wanted to reduce the heating, but my wife now says she's sure it was like that since it was installed.