Synchron motor failure

In my last house with 3 zone valves I found the motors never lasted more than 3-4 years !

Does the valve move freely with the motor head removed? It could be that its putting undue preasure on the motor which is causing it to fail.

Alan

In 15 years with three zone valves I haven't had a single motor failure. Microswitches are another matter!

Agreed, has the motor really failed or is there a small lump of crud in the gear chain or in the valve. These motors have naff all torque and it doesn't take much to stop them.

The one on out CH was playing up recently, not quite getting far enough to operate the switch. Took it off, cleaned crud from the cog, might have regreased it, it's been fine since.

SteveW

That's unlikely to be the problem because the motors are designed to stall with the power still on when they reach the valve open position. If the valve is seized, the motor will just stall a bit earlier - but it won't hurt it.

Having said that, a perfectly good motor will, of course, fail to open a seized valve. Are you (the OP) *sure* that the new motor has failed. If you remove the actuator from the valve, does it still not move?

It seems to be fairly easy to move. I haven't taken the head off my CH valve to compare but I can open and close the valve with my fingers.

With the motor removed it doesn't spin even though I'm measuring 240v across the terminals.

David

In that case it looks like the motor is duff. It could just be a poor specimen which would have failed after half an hour whatever you did to it, rather than being the result of something you (or the valve) did to it. Send it back for a replacement.

As long as a pump i.e. 1-25 years. I think you were unlucky, the motors are designed operate 24/7 in the stalled condition so there are no real external factors which can screw them. Wrong supply would but that in very unlikely.