Faulty 3 Port Valve

[Photodom]

I had what I thought was a faulty 3 port valve actuator. I removed the head and tried to turn the valve manually on it's spindle. It is incredibly stiff, and the only way I can move it is to use a pair of pliers. I would imagine that for the motor to operate the valve properly, the valve should be spinning freely. Is this the case? If it is stuck, would the motor burn itself out?

Can anyone confirm if the above is correct so that I can try and fix the problem - February in Scotland is not when you want to be without Central Heating.

Thanks

 

[ollski]

yes your motors will be burning out...what valve is it?

 

[Photodom]

The actuator is a Sunvic. The whole thing was fitted as new when the house was built 7 years ago. Would it be debris in the pipes causing the valve to stick or simply wear and tear. All water coming from rads and the pump bleed point is clear - not black which I have been told means some corrosion?

Thanks for replying.

 

[oilman]

If you wiggle the spindle about a bit with a spanner, you may be able to loosen it. If you can't get a Sunvic valve, a Danfoss HSA3 is a possible replacement.