Motorised valve or programmer?

[StephenCampbell]

Hi there,

About a week ago we lost hot water, but CH was fine. I just stuck the 3 way valve on manual override for a few days until I had more time to look into the problem.

I've had the clip-on cover from the valve off and back on again and have fiddled around with the programmer to see whther the actuator was working and what it was doing. With CH and HW selected, the radiators are on full belt; the system doesn't respond to the room thermostat (valve is at "H" position). With only CH selected on the programmer, (HW turned off), the valve seems to respond normally - moving to the "H" position when the room theormostat demands more heat and returning to the "W" position when it's warm enough. So, selecting HW on the programmer seems to cause the valve to respond with continuous CH only. Which has got me foxed!

Any advice gratefully received.

Thanks in advance.

Stephen

 

[seco services]

if your only calling for heating and hw off at programmer.
and the heating is satisfied then it should stay in the h position as it willbe held in last position by the grey wire.

 

[StephenCampbell]

Thanks for the quick response, which is very much appreciated. Sorry if I didn't explain things very clearly. What I don't understand is why the CH will not trip off when it reaches the room stat temperature if HW is selected at the programmer as well as CH, but will trip off if only CH is selected at the programmer. Do you mean that you think there's a problem with the voltage hitting the grey wire? Would this arise from the electronics in the valve or the programmer? Or somewhere else entirely?

Thanks once again.

 

[seco services]

the hw side doesn't really have nothing to do with the valve as such.
only the grey wire.

if you have heating on, hw on and both calling for heat at the stats
the valve should be in the M position.

if you have heating on hw on and the heating becomes satisfied.
the hw will still keep the boiler etc going.

you need to do a few tests.

if hw/heating calling what is the valve pointing to W M H ?

 

[StephenCampbell]

Thanks; I'll check how it responds in the morning when things have cooled down.

As of tonight, the valve was moving from H to W when the heating stat was satisfied, but only if hot water on the programmer/timer was turned off. With hot water "on", the valve remained at H, even when the room stat was satisfied, leading to red hot rooms I realise that the hot water setting shouldn't affect the heating: that's why I'm confused! I'm *presuming* hot water is satisfied, which might explain why the valve was not moving to M, but as I say, I'll have another look in the morning after the showers have run off the hot water!

 

[seco services]

the valve was moving from H to W when the heating stat was satisfied, but only if hot water on the programmer/timer was turned off.

should stay in its last position. H

With hot water "on", the valve remained at H, even when the room stat was satisfied

if that was last port of call. hw may of been on at timer but satisfied by the cyl stat.
thats correct