Honeywell room thermostat change

[taylorhouse]

Hi. I want to replace my old Honeywell room stat t6060 I think with a new t6360. There are 3 wires in my old one. Black : number 2. Red : number 1 and earth : 3. can anybody help. Lookig at the diagram I think I need 4 wires and not 3.

[/quote]

 

[stem]

They both require the same connections, however the original installation is badly installed because the earth wire is being used as a switched live. So there isn't an actual earth connection.

In the lid of your old 6060 there should be a wiring diagram which if I remember correctly will be.

Terminal 1 = Live
Terminal 2 = Neutral
Terminal 3 = Switched Live
Terminal 4 (not used in your application)

The new 6360 thermostat uses exactly the same configuration. If it does need an earth connection though, you have a problem. Check with the manufacturer's instructions. Even though there is an earth terminal provided, doesn't necessarily mean the thermostat needs an earth connection.

 

[taylorhouse]

Hi and thank you for your reply. There was no wiring diagram for the old one. However looking at the wire it seems to be as you stated. The new one needs 2 wires if the system load is over 6amps and 3 wires if below 6amps.
Not knowing what my system is i have tried both. When using 2 wires the fuses blows stright away. Using 3 wire the centeral heating is on all the time even if the main control unit is not in the heating on position. Don't know what to do next.

 

[D_Hailsham]

How did you wire the new stat?

 

[stem]

You seem only concerned with the number of wires. What is far more important is what wires go where. If your new thermostat only needs two wires, do not use the neutral as one of them. If you managed to blow a fuse that is probably what you have done. You may now have damaged the new thermostat.

Anyway you now need to answer the question posed by D_Hailsham.