Is my heating programmer at fault?

[Surrey101]

I have recently replaced my mid-port valve as had died and also my thermostat for good measure. Replaced with like for like (Honeywell / Sunvic). All working great but during afternoon the thermostat stays on and will not turn off. When I reset the programmer all goes back to normal. Have gravity system with Potterton boiler.
Any ideas????

 

[motorbiking]

Are you saying it doesn’t click ?

 

[transam]

hang on u say u have a 3 port valve

must be fully pumped ??
U say gravity ?????

 

[Surrey101]

Sorry yes, it is pumped but not a combi boiler. The thermostat clicks on fine and seems to work fine. However, on 2 occassions have come home to hot house and not so hot water. When tried to turn down thermostat nothing doing. Light stays on and will not click off. When I reset programmer / or turn system off/on then ok.

 

[transam]

Assuming valve has been changed wire for wire ?

room stat the same ??

than logic would point to the programmer ??? Is at fault ?
Possibly ? May be ?

 

[Dangee]

Are you sure cylinder stat & room stat wiring hasn’t been crossed.

 

[Ihavenojob]

When tried to turn down thermostat nothing doing. Light stays on and will not click off.

What roomstat, is it a Drayton digistat ? They have trouble with relays sticking, but it usually sticks so it won't turn on. Lots of videos on youtube about it if it is.

 

[Surrey101]

No its a Sunvic TLX9021

 

[Surrey101]

Will recheck the room stat / cylinder stat wiring as took a pic prior to changing but expecting all good.