Replacing honeywell T40(T6360B) thermostat for wireless stat

[D_Hailsham]

If I can get another cable to the thermostat receiver can I do this so that it is also still controlled by the timer

N = Neutral
L = Perm Live (new cable to patch panel)
A = Timer Live
B = Switched Live

The wire to A has to come from the CH ON terminal of the timer not the Live terminal.

If you are replacing the existing cable with a 4-core, trace the existing cable back to the junction box and then wire the new cable as follows:

New cable - Old cable Terminal
Brown ------- Permanent Live (This is a new wire)
Blue ----------- Blue
Colour 3 ------ Red
Colour 4 ------ Yellow

At the relay:
Brown to L
Blue to N
Colour 3 to A
Colour 4 to B

 

[stem]

Apologies for the incorrect information earlier. I have only ever seen a R6660D supplied with a CM921 which is a programmable thermostat and as you didn't state what the thermostat was I just assumed that was what you had. Just shows you should never assume.

I will leave you in the capable hands of D Hailsham and wish you a successful conclusion to your project.

 

[sparkler13]

thanks stem, maybe I should have known to be clearer working in TAC support, i get this all te time people leaving out important info!!

Anyway further info, I have checked voltage on Live when timer is off on CH and I have 40V, is this normal? Does this mean I do not need to put in a an extra live, would 40V be sufficient ?

 

[D_Hailsham]

Anyway further info, I have checked voltage on Live when timer is off on CH and I have 40V, is this normal? Does this mean I do not need to put in a an extra live, would 40V be sufficient ?

Simple answer: NO.

 

[sparkler13]

Just an update for others that may come across this thread, all wired in as follows and work perfectly :-

T40 ---------- Relay

Terminal 1 ----- A (this is connected to Programmer CH ON terminal)
Terminal 2 ----- N (probably connected to Programmer N terminal)
Terminal 3 ----- B (this is the switched live)

New wire
Permanent L to Relay L


Thanks for your info D_Hailsham