Elec Room Thermostat to replace mech Timer

[Giblets46]

Hi, as my system has no Room thermostat, i have decided to replace my mechnical timer with an electronic timer/ room thermostat.
Here I am a bit confused. The mechanical timer appears to have its own electrical supply and two wires connected to the combi boiler. I want to replace it with a Hirstmann DRT2.

The Thermostat is a Horstmann DRT2, which has a
'no',
'com' and
'NC' connections in it (it is battery powered).

I want to connect it to the chaffoteaux et Maury Britony combi 80.
This has
1.Neutral,
2, Phase,
3, Room Thermostat live
4. Accelerator Resistor
5. Common for Accelerator and room thermostat

The horstmann instructionsa re pretty vague and suggest connecting the live to the 'Com', then the 'No' to the 'heater (or NC depending on the type of heater); and the neutral from heater to the Neutral.
So how should I connect this up? Seems very confusing
Cheers
Edward

 

[PaulAH]

You can work it out
NC = Normally closed. COM is connected to this when it's off (no call for heat)
NO = Normally open. COM is connected to this when it's on (calling for heat)

Accelerator needs to connect when it's on. This speeds up the stat's slow response to the room heating up, so it switches off again earlier than it would left to its own devices.