Room Thermostat

[richardr35]

Hi,

I am trying to replace an old room thermostat (Switchmaster) with a digital version (Drayton Digistat 1).

I don’t have any instructions and would really appreciate some advice on how it should be wired-up.

The old Switchmaster has five terminals, three of which are connected as follows:

T1 = red (only live when heating turned on).
T3 = yellow (does not appear to do anything!
T5 = Earth

The Digistat has three terminals:

1 = C
2 = Sat
3 Call.

Can anyone tell me if the Digistat can be fitted and if so, how?

Many thanks,

Richard

 

[ArtfulBodger]

Your yellow should come live when there is a call for heat. Check this on the box or back at the wiring centre.

If this is the case, then red to common T1), yellow to T3 on the digistat, no earth required.

 

[ChrisR]

Let us know if still baffled - I've got it in a book somewhere!