Swapping Drayton RTS1 for digital thermostat - Wiring question

[Wraxity]

Hi all.

Im trying to replace my Drayton RTS1 with a digital thermostat. I can get power just fine, but I can't for the life of me figure out where terminal 3 on the existing block should be wired to on the digital thermostat.

See below pictures. (this is for heating only, as water is controlled by another unit in my kitchen).



Can anyone suggest how to proceed? Please.

Thank you

Tom

 

[Johnmdc]

Connect the yellow wire to terminal 2 on your new thermostat, you will also need a short length of wire to link terminals 1 and 4.
You will need to set your existing programmer so that heating is on constant for the new thermostat to work correctly.