Worcester Heatslave - heating issue

[rubber_hammer]

The head contains a microswitch which brings on the boiler with pump when the valve is moved to a position.

But it is most likely to be only a failed motor. Just changing that is likely to be the easiest and cheapest option. Often called Synchron motor as that is the brand name of a well known manufacturer.

Often available for around £10.

Does the motor play any part in bringing the pump in - as I have the valve manual switch pushed across to give hot water to the radiators, but the pump still doesn't turn on. The pump will only turn on when the boiler is firing for hot water (either when bring the water up to temperature or when a hot water tap is opened).

I did flip the manual switch back to auto just now and it does not slide all the way back. It sticks about half way - I can push it the full way across, but the last bit has little or no resistance, so is quite loose. I don't know if this makes any difference, but I thought I'd mention it.

Could the motor be knackered to the point where it is not switching the microswitch? Might be time to take it off for a proper look.

Naturally, I'd rather just pay out £10-20 than almost £200, if I can help it. Note that I can only find the heads in this model with the valve body included.

Many thanks!

 

[Harry Bloomfield]

The head contains a microswitch which brings on the boiler with pump when the valve is moved to a position.

But it is most likely to be only a failed motor. Just changing that is likely to be the easiest and cheapest option. Often called Synchron motor as that is the brand name of a well known manufacturer.

Often available for around £10.

Some can be quite fiddly, worthwhile buying a complete new head, then tackling the failed one to repair it, to keep as the spare, as I used to do.

 

[Harry Bloomfield]

Naturally, I'd rather just pay out £10-20 than almost £200, if I can help it. Note that I can only find the heads in this model with the valve body included.

Often an indication, that the head is permanently attached to the water valve.

 

[rubber_hammer]

So, after having a closer look, the head does detach from the valve body - that's a positive. The reason the pump wasn't being powered is because the micro switch was not being released. I messed about with it to try and adjust the lever position - it seemed ok until I put the head back on the valve spindle, but this has resulted in the micro switch being permanently on, so will need a bit more playing about with.

I think the synchron motor is knackered though, so I'll replace it.

How much resistance should the valve spindle have? I can turn it by gripping it with my finger and thumb but it's quite tight - much easier with a pair of grips. I assume that's ok?

 

[Harry Bloomfield]

How much resistance should the valve spindle have? I can turn it by gripping it with my finger and thumb but it's quite tight - much easier with a pair of grips. I assume that's ok?

Yep, that is normal.

I think the synchron motor is knackered though, so I'll replace it.

You can simply apply mains across the motor terminal wires, and it should run.