Problem with Central Heating Controller. CH command switching HW too, not valve prob.

GBY

Hello,

I recently had a new 3 port valve fitted as the previous one had packed in. The valve is now operating correctly. Although the Potterton EP2001 had been functioning correctly it is now acting rather strangely. Switching hot water is fine, but whenever I switch on the CH the hot water comes on as well as the heating. It actually switches it on at the controller!! I have changed the internal battery as it was low and I know this can cause some problems but I suspect something was not wired correctly when the valve was installed by the plumber. I have asked him and he says the work could not have affected the controller. However, it is a strange coincidence and I do wonder whether there is any tally back incorrectly wired that could be causing this.

Does anyone have any suggestions before I trace the wiring?? I have diagrams and am aware mains is involved.


Thanks.

Canucklehead

Hi

Your plumber would not have needed to open up the programmer (unless it was used as a juction box)
It sounds like it is working correctly the way it is wired up (when the cylinder stat is satisfied it will swing to c/h only) but it should be possible to wire it so they are independant.
Check the sliders on the programmer are in the correct position. (the one where you move it to set the times etc must be in the 'run'? position.)

Corgi Guy.

Fred56

Try turning down the temp on the hot water cylinder thermostat until it clicks. Try your heating with the cylinder stat in that position. The valve should move to CH only assuming the rooms stat is calling for heat - turn it up until to make sure. Modern digital rooms stats tend have a 1 minute delay so if you have one, give it a chance to make its mind up.

Don't forget to put the stats back to where they were when you've finished testing.