glowworm boiler problem

[johnfh]

I have a conventional Glowworm boiler installed 3 years ago. All was fine but boiler now ignores programmer and is on all the time unless power switched off.Also does not heat water now. Suspected programmer fault so changed it but problem remains. Any idea what the fault is?

 

[ollski]

2 x 2 port motorized valves?

 

[johnfh]

No just one Danfoss Type HSA3 motorised valve

 

[Soggy_weetabix]

stuck valve

 

[bab]

can u remove the head & see if u can move the spindle with ya fingers. If not a sqirt of wd40 & work it free then try head again.

 

[johnfh]

Thanks Ill try that as soon as I get home from work!

 

[croydoncorgi]

For general information:

Most faults involving stuck Honeywell motorised valves end up with the valve open but the internal switch not operated, so (for example) you will get the hot water heating up only when the central is running, or vice versa.

But other makes of valves often (but not all types) operate the internal switch and open the valve together, so you can get the boiler working against a mostly-closed valve (overheat!) or the system running all the time even when the CH is off at the programmer.