Central Heating: Radiators not working. Hot water OK

[Rincewindwiz]

Hi,
Arrived back late after 3 weeks away. Fired up central heating and went to bed. Next morning I noticed the radiators were cold. Hot water is fine. Fiddled with the room thermostat and could hear it click on and off.
Fiddled with the main timer (On/Once/Twice/off) and could hear the pump start up.

Discovered the Actuator (Drayton TA/M4) with lever pointing to 'Hot water' and not 'Heating'. Nothing I did to the other heating controls seems to make a difference to this setting or to get the lever to move.

I tried moving the lever by hand but could not move it and did not want to try to hard and maybe break something.
so:
1. Any thoughts on the problem of cold radiators?
2 Am I supposed to be able to move the metal lever on the actuator from 'Hot water' to 'Heating' and will that solve the problem
3 How hard can I reasonably force it
And any other helpful ideas you may have
Thanks in advance

[stoneyboy]

Rincewindwiz,
Sounds like the valve has seized.
You could try more force on the actuating lever but I think these are plastic and it's easy to break them inside the head. If the head is removable take it off and try operating the valve directly.
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[Rincewindwiz]

Thanks for the thought.
Eventually worked out how to the the actuator off and the value then works just fine manually.
So now I just have to figure which bit of the actuator is broken

[stoneyboy]

Rincewindwiz,
Buy a replacement head - saves a lot of hastle.
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