Radiators only getting hot when the water is being heated

[wesley1978]

My central heating is only coming as the water in the cylinder is being heated. Once the water has reached optimum temperature instead of reverting to just heating the radiators it clicks off & the boiler reverts onto standby & the radiators go cold. If i turn up the stat on the water cylinder the heating comes on again & heats the radiators but for only as long as it takes to heat the water again. I hope this explains my problem & somebody out there can help.

 

[Armo74]

Assuming you have a 3 port valve it sounds like it is stuck in mid-position.A temporary solution would be to turn your cylinder stat up a little and your boiler stat down a little that will give you heating as long as you have the programmer set to hot water. Please bear in mind this is only a temporary fix.

Or the other option is to isolate the electricity supply remove the actuator from the valve body and gently try and free it yourself.

 

[seco services]

Or poss the 3 port is not getting 230v on the grey wire from the hw satisfied/off
or faulty micro switch or valve not fully activating micro switch to give 230v on the orange wire on ch only.

 

[Armo74]

As seco services says aswell it could be a number of things which is usually down to a process of elimination.