Wiring to replace old Honeywell thermostat

[eddibo]

Hi, I've bought a ThermSave Celect LCD3 programmable thermostat to repace an old manual Honeywell room thermostat (no programmable timer in the existing system).
Can anyone help with the wiring connections?
The Honeywell has 4 terminals - all with current when I use a test screwdriver. Currently connected are a red wire to terminal 1 and a black to terminal 3.
The new 'stat has 3 terminals: 1=NO, 2=COM, 3=NC

Any help appreciated....

 

[gas4you]

Red wire to com,power in, black wire is switched live back to boiler. Try this on 3., but needs to be connected tocall for hest conector.

 

[eddibo]

Thanks for the reply - I had fought through the hangover & worked it out though! For the record, red to common & black to 1 (normally open) was the correct sequence. Cheers.