Motorised valve not doing what it should???

[tippers]

We have a combi-boiler system in which if the motorised valve is set so the water goes to heat the water (which can be achived by turning off the mains power) when the water heating thermostate is turned up - the boiler powers on and the water get heated, as it should.

If you then turn down the water heater thermostate so the boiler turns off and turn up the room-thermostate, the boiler turns on and the switch in the motorised valve turns to point to the radiators - and the radiators heat up.

Which so far sounds fine - however if I then turn the room thermostate down so the boiler turns off, the motorised valve stays where it is - pointing at the radiators. Then when you turn up the water heating thermostate the boiler turns on but the motorised valve does not turn back to point to the position to heat the water - instead it stays pointing towards the radiators and so the radiators heat up but the water doesn't.

Has the motorised valve's motor gone, even though when the heating is turn on it definitely moves from the original position to heat the radiators?

Or is something not sending a signal to it to move it back to position for the hot water?

I hope you can help,

 

[breezer]

Has any thing else changed? i should say that as the valve is a moving part and has a coil in it it is this that has given up. It would be worth while checking before you buy a new valve though, do you have a mains tester or meter?

 

[simon]

You can buy a new synchron motor for the valve about £20

 

[tippers]

Thanks for the advice, - though if the motor had gone why would it work when the valve is moving from the hot water setting to the radiators setting - surely it would just stick in place?