heating won't swich off?

[dml]

Have a job where although the programmer is off the rads stay on, everything seems to be working including the boiler, could it just be a programmer replacement?

 

[plumbnuts]

Check operation of motorised valve and replace the motor if required.

 

[buffy27]

what type of boiler is it.some times boilers in a shed or out doors may have a frost stat.permanent live supply,activated depending on setting.


or are u saying that when u want hot water only ,the rads are heating also? if this s the case it may be a motorised valve letting water by for some reason.check the room stats-really depends on how the controlls are set up!!!!!

 

[sonray ltd]

Check operation of motorised valve and replace the motor if required.

where does the motor come into it.
if the system is a y - s plan and the heating is still running and the valve is calling for heat where does the motor come into it ?

a motor only opens the valve not close it.

 

[plumbnuts]

Sonray
Get over yourself!
What type of system is it then?
Could it not be the motorised valve then?
Just giving sugestions that might help with the limited informtion supplied.
Maybe it's the aquastop valve?
I thought that the aim of this site was to help people in need?
If you have nothing constructive to say to me, please don't bother.

DML
Please supply further informtion about the type of set up that you have. Thanks

 

[sonray ltd]

If you have nothing constructive to say to me, please don't bother.

your suggesting the motor in the mot valve is at fault.

a motor only operates the valve to open not close.
if you remove power from programmer calling and any stat calling
then the valve will fall to its relaxed position by a spring not a motor.
or beheld in last position on a 3 port valve by the grey wire.

if the valve has no power to it and the valve is still calling for heat then the valve is stuck but not by the motor.

this will only happen on a zone valve not a 3 port valve.

as a zone valve always has a perm live on the grey.
a 3 port never has a perm live.
only live is from the white or the grey and its not perm.

so don't say my advice is not constructive
you need to understand how valves work first.

 

[dml]

Thanks guys, he is more detail.

Even when the programmer is switched off and the room stat turned down the heating stays on with the rads red hot - I think it's the motorised valve but would like conformation.

Many thanks.

 

[sonray ltd]

what valve is it a 3 port mid position or 2 port zone valve.
and name or model numbers on the lid.

 

[plumbnuts]

Sonray
I am well aware of how a MV works, Have you never come accross a 2 port that sticks open then? This would cause the heating to stay on.

DML
Do you have 2 motorised valves? 1 for the heating and 1 for the hot water?

 

[sonray ltd]

yep a 2 port will stick open due to spindle seizing or stiff.
a micro switch will stick aswell.

but none will be due to the motor.
the motor only plays a part if heat is called for.



(Check operation of motorised valve and replace the motor if required.)