please help, odd problem with heating...

[iany]

that's the weird thing...

if i turn on HW the white wire gets power.... its almost as if the turning on HW kicks the CH relay inside the timer box into life??

the voltage at the room stat is dead unless HW is on, once on that's live and as a result when activated it sends a voltage down the white wire.

If HW isnt on white wire is dead, HW on and its got voltage.

just read a thread on another site with exact same issue with same controller and unfortunately it didnt get to a resolution!! typical...

http://www.electriciansforums.co.uk...s/55870-strange-fault-drayton-programmer.html

 

[stem]

When you changed the motorised valve head earlier, was this because of exactly the same symptoms?

When you did change the head, did any of the symptoms change?

If the wiring is as it should be, then the wrong signals are coming from the programmer, then that will likely be your problem.

I can think of a couple of things to try. Either a programmer swap, or take the programmer off the wall and wire it up to a couple of lights to simulate the HW and CH signals and see how it performs switching them on and off.

 

[iany]

as far as i remember its no different after fitting it and that was the reason i swapped the head off the mid position valve.

stripped the programmer and no obvious broken bits but its all on a PCB so hard to tell, cleaned contacts and replaced but no change, gonna try a new programmer and see if that sorts it...

 

[stem]

You could try moving the central heating 'on' wire at the programmer into the same terminal as the hot water 'on' wire, and try it for a few days and see what happens. OK, both parts of the system will work according to the hot water set times, but if it works OK then you can be pretty sure it is the programmer that's at fault.

 

[iany]

took a gamble and just grabbed a new programmer from screwfix, its working now

got a slightly different model as it was cheaper and also worried that the others may be prone to issues....


thanks for your help in diagnosing this, i've learnt a fair bit along the way about how the black magic of heating works, not as complicated as i thought!!

 

[gigz]

had a further mess around since last reply...

if i start with neither on, then turn on CH, nothing happens, 3 way stays in position A (HW)

Know its sorted now and i don't know if this is rellevent but HW is port B.

 

[stem]

took a gamble and just grabbed a new programmer from screwfix, its working now

Good, glad to hear it. I hope you don't have a similar experience to the other post where it failed again after a short time.

[I don't think you will though]

 

[gazdaz36]

I know you've sorted it now but from what you say it's almost as though the programmer was set up for a gravity hot water system.

 

[iany]

I thought that too, the original had a switch on the back to run like that or as seperate systems, I tried to set it to gravity and both worked as expected, when set back to normal it had the issue, thinking about it maybe the fault is in the region of the switch within that circuit as that's the point where the two independent cuircuits could get power from a single source...

only difference was when in gravity mode when you turned the heating g on it turned the hot water on too.