Heating fault

[Silverspeed]

Central heating has a wireless stat and frost stat. Heating and water have motorised valves. Heating room stat call for heat but boiler doesn't cut in. Tried turning frost stat up to see if it was a controller issue but nothing. Hot water works fine so thought it was the Heating side motorised valve. Manually opened the honeywell valve but the boiler still won't cut in on the heating cycle! When the water calls for heat pump cuts in and everything works. If I manually open the heating valve the rads get hot on thd heating cycle. At a loss now what the issue is. Help would be greatly appreciated. Thanks

 

[hansthebear]

i would try re-syncing the wireless stat to the receiver

 

[Silverspeed]

Thanks will try that but surely by turning the frost stat up this should override both the controller and wireless room stat?

 

[5544]

is this a recent problem. in other words has it worked fine before.
initially i would ignore the frost stat. look at the heating first. does the wireless room state provide 230 volts to the wiring centre when the room state calls for heat. (check this with a multimeter). If it does not, check the batteries in the room state as they might be strong enough to power the room state but not enough to send a signal, or as previously mentioned re sync with the receiver) if it does provide 230v then does the motorised valve drive over on calling. (if it does not check continuity of sychro motor, if there is no resistance, change). If it does drive over, do you get 230volts from the motorised valve back to the wiring centre to power the switched live to boiler and pump? if it does not, its the valve.
(remember that s plan valves have a switched and permenant live on them)

since the water works i suspect it is an electrical problem on the heating side which can be easily be worked out if you just follow the path of electricity to the boiler.

 

[bengasman]

Drayton stat by any chance?

 

[picasso]

micro switch knackered on the heating 2 port valve, just change the head, I think the heads are about £50.

 

[Silverspeed]

Thanks for the replies. Just what I feared. The valve it's in an unbelievably bad place to get to! Think need to take megaflo out to reach it! Why did the builder put it there?