xtinexoop wrote:

Hi

We have a problem with the central heating. I think we have narrowed
it down to the motorised valve which is a Myson 3-Port valve.

The problem is that although we have hot water the heating doesn't
come on unless you use the manual override lever. We can see from the
lights on the actuator that the timer control is passing the right
'signals' to it, but it isn't opening the valve.

I had a look on the Myson website and it is possible to buy the
'actuator' bit seperately and its 4 screws and some simple wiring to
replace which having taken the current one off to have a look I think
I could manage. The alternative would be to buy a complete new valve
but I understand that would require draining the system and would be
beyond my capabilities and expensive to have done (a quote to replace
it with a Honeywell valve is £150+VAT).

Can anyone tell me whether it would be false econonmy simply to
replace the actuator - is it like replacing the disks in a car and not
getting new pads at the same time for example?

Any suggestions gratefully accepted.

Thanks

Christine

Provided that the valve is moves freely just changing the motor should do
the trick. make a sketch of which wire goes where and then take the old
motor with you when you buy the replacement just in cas eit is a bit
different or there is a choice of motors.

Good luck

Bob