Heating wiring help

kevh1987

Hi all

I am looking for some help to see if I could make my heating set up run a bit different.

I have 3 zones in the house upstairs, downstairs and HW, with an oil boiler and solid fuel stove with back boiler.

I have the power for the oil boiler ran through a NC contactor with the other zones ran through NO contactors.

So for each zone the switch wire of the stat for that zone is connected to A1 of the contactor for that zone along with the live for the pump of that zone, thus bringing on the pump for that zone and oil boiler.

The switch wire of the stove stat is wired to A1 of the NO contactor, thus bringing on the stove pump and knocking out the boiler.

Now here is my problem, when the stove is on I have to manually turn on the Timeclock to bring on the upstairs and downstairs pumps to send the heat to those zones.

Is there a way I can wire it so when the stove pump kicks in it will automatically bring on the upstairs and downstairs pumps?

Thanks in advance for any ideas.

brightspark

any chance you can sketch your current circuit?


(I think you will need to use a no contact on the same contactor that the stove brings on to effectively short out the timer contact)

kevh1987

Hope that diagram makes sense.

brightspark

can you post a pic of the contactors too?

kevh1987

I could tomorrow, they are just double pole 25a contactors. The way its wired works fine but i would like that when the stove kicks in it also brings on the upstairs and downstairs pumps.

brightspark

As I suggested then one of the contacts on the contactor that is brought on by the stove could be used in parallel to the time switch?

kevh1987

So finally have an update on this. I took your advice and changed the 2 pole NC stove contactor for a 4 pole, 2 Open, 2 Closed contactor.

The NC contacts isolate the boiler and the NO contacts bring on the upstairs and downstairs pumps.

All seems to be running well now. Thanks for your advice.