Wiring central heating controls

[Will]

I have a Potterton Performa 28i combi boiler.

At present the timer is a fixed mechanical type and I do not have a room thermostat fitted.

I want to install a Drayton Digistat 1 Thermostat (battery operated) and a Drayton Tempus 1 timer (mains operated). I need some clarification on the wiring.

There are 2 connections from the boiler pcb (1 and 2). However there are 3 connections on the Digistat. I assume I connect terminal 1 from the pcb to the com terminal (1) on the Digistat. Terminal 3 (call) on the Digistat to terminal 1 (com) on the Tempus. Then terminal 3 (on) from the Tempus back to terminal 2 on the pcb. Is this correct. I have a seperate feed, live and neutral into the Tempus 1.

[Sparks]

Sounds fine to me!

The three terminals on the stat will be Com, Call for Heat and call for cold (Air Conditioning) so make sure you use the correct two, or it will end up calling for heat when it doesn't want it!

Sparks...