Motorised Valve Sticking / Stuck?

[Pete_S]

Hi All,

Buried somewhere here is some info regarding how much force is required to establish that a three-port valve is not stuck. I seem to recall that you should be able to turn with finger pressure or possibly small pliers wrench?

Further, can someone advise how far a healthy valve should be turning. The Drayton unit under suspicion seems to move about 1/8th of a turn.

Thanks in advance,
Pete Springfield

 

[kevplumb]

they usually move more than that

 

[MANDATE]

The valve spindle should have little resistance and turn using finger and thumb. You would not need any tool.
Regrading actuators, would think they are all the same. The actuator on the myson moves 45 degrees from rest position (HW) to mid way and another 45 degrees to the CH position. If you can take the actuator off the valve you can watch it move as you choose CH or HW or both. Also you can check the voltages on the 'white' 'grey' and 'orange' wires in the terminal box under the various positions.
Most problems appear to be the 'motor' or small pcb in actuator head containing microswitches.
Sounds as though yours can't get past mid point.

 

[Pete_S]

Thanks for the replys chaps,

I've now managed to examine a new Drayton unit identical to mine (courtesy of B&Q of all places!) and the shaft movement is identical, a mere 22 degrees.

Unless, I am suffering a sticking microswitch (as helpfully explained in a nearby thread) which would explain the pump overun part of my problem then the 3 port valve is OK.

Cheers,
Pete

 

[ChrisR]

Yes they don't move much!
Wot boiler - maybe you said on other thread?
Find the connections to it.
When the pump is ON but you think it shouldn't be, see if the Switched Live terminal is live, and if the Pump terminal is live. Simple as that really.