Hot water ok, no central heating

[freddier]

I have a ACL Drayton LP722, the hot water side is fine, however the central heating simply does nothing. I've bled everything I can find to bleed, several times, to no avail. I can get the rads nice & hot by manually switching the mid position valve with the hot water side on.

Any thoughts?

 

[fuzzy]

motor gone on 3 port. try manually moving it and locking it into mid position

 

[freddier]

Thanks fuzzy, locked into the mid position but still no response from the boiler when the thermostat clicks.

 

[fuzzy]

arrhh, seems like a wiring fault then, if you are competent to do so you could link out the stat to see it it fires

 

[freddier]

Would that be to short the "Call" terminal bact to live?

 

[craig gas]

check white cable on mid pos valve if 240v present when controls are calling but lever isnt moving valve is faulty probably get away with changing motor

 

[freddier]

Thanks Craig, would a faulty motor still account for the boiler not firing when the C/H stat "clicks"

 

[craig gas]

yes when calling for heating the boiler will not fire untill valve has opened and microswitch in actuator has made

 

[RoryD]

should have 240v at the white wire in wiring centre, if you have then check if you have 240v on the orange wire, if no then replace diverter. If yes the fault is back at the boiler

 

[freddier]

Thanks Craig, with that as the case it sums my promlem up to a tee.
Rory, Thanks. I'll check for voltage before I change the actuator motor.