3 port valve running hot

[davidxm]

can anyone please help?
I have just replaced a 3 port central heating/hot water valve with a new Wickes model and wired it in as the previous one. 4 wire + earth (Blue/Orange/Grey/White/Green-Yellow).
The valve appears to control the water OK but the internal drive motor is too hot to touch even when both CH and HW switched off!
Any ideas?
Regards
David

 

[mysteryman]

It will be driven to the CH only position [grey wire live] when the controls are both off. The motor is mechanically stalled, but still drawing about
3 watts of power. This may keep it hot, but if it is overheating or getting smelly, it may be worth asking Wickes what they think.

 

[davidxm]

Yes, the grey is live. It takes a little while to get very hot (too hot to continue touching for more than a few seconds) but it doesn't smell.

Thanks for the advice.
Regards
David

 

[ChrisR]

Sounds wrong to me. There are lots of cheapa motors about. A "Shorted turn" in a motor like that could make it run very hot.
SHould be under a Watt when it's stalled, unless there's something else wrong in the head.
Sling it back at Wickes saying it doesn't work any more.

 

[davidxm]

Thanks again to those who gave me valuable advice.

In order to help anyone else with this problem, the current situation is:-

Returning the old one would have entailed drain-down and removal - not easy and I didn't have a receipt. So I bought a new one, it's Wickes branded but Siemens manufacture.

I connected it in (electrically) and waited for 30 minutes - lo and behold it operated perfectly but was too hot to touch!

So I returned it and had a refund and saved myself a lot of work.

What a strange design !!

Regards

 

[oilhead]

your problem can be resolved by replacing the programmer with one that kills the supply to heating when not programmed. Most modern programmers include this interlock.
The design of the valve is common to all manufacturers of spring return actuators. If at the end of a programmed heat period there is still a heating demand, then the valve is held at stall until the next timed period.
Alternatively, you can fit a motor open/motorclose valve.

 

[mysteryman]

It is the DHW off connection from the programmer to the grey wire on the valve which holds the valve fully motored when everything is timed off.

 

[davidxm]

Thank you for such a concise answer.
Unfortunately I can't check the programmer for some time because the owner (my son) is on holiday.
Although I don't know the programmer details, I know it's very modern as it was installed within the last year.
When I get a chance to check it what connections should I be looking for and is it a case of swapping existing wires or will it need new wires between programmer and valve (not easy).

Thanks again
david

 

[mysteryman]

I think you are worrying over nothing - this is the usual layout.

 

[davidxm]

I know! I'm a natural worrier.

Although the internal drive motor housing is too hot to touch, the outer aluminium casing is just warm to the touch, so there's no fire risk.

It just seems a great waste of energy and surely must reduce the life of the valve?

Thanks for yours and others posts which have helped me immensely, keep up the good work.

Regards David