Motorised valve problem

11 May 2013
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United Kingdom
I have two 22mm 2 port motorised valves.
the heating motorised valve is working, but I get heating and hot water when the heating ONLY is switched on.

The hot water motorised valve is not working. I get a light on my Neon from the motorised valve when selecting hot water on the programmer, but there is no motor noise.

It was fine in the winter - we had just heating on the programmer, and we got heating and hot water.
Now its Summer, I'm having to have the heating on , to get any hot water.
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Light on your neon - must be power then, only thing is we dont know where the neon is/was and they are totally unreliable. You need a meter to test for electricity
It seems the HW motor valve is jammed open but not moving to operate the microswitch.

Regardless it needs investigating.

What are you going to do now?

Did the system used to work properly and now it doesn't or have you either moved in or had new work done and don't know if it ever worked properly.

Do you get motor noise from the Hot Water Valve when the Heating is put on?

What are the makes of the valves?
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I've been in the house about fifteen years. It used to work fine, and only noticed the problem about six months ago.
There is no noise from the hot water valve when the heating is put on.

the valves are ACL, although the synchron motors are universal type.
You can check the operation of the valve manually.

It will (I think) indicate positions A and B for closed and open positions respectively
There is usually a separate lever to manually open the valve. Most operate on a spring return to close them. i.e I will normally be at A moving to B when heat is call for or when you manually move the lever

You need first of all to check that it is not jammed partially open.
I would suspect that after 15years the whole valve will require renewing, it might just need a motor or actuator but some older valves cannot be split.

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