Honeywell DT90E Thermostat

22 Dec 2011
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United Kingdom
I have just purchased a Honeywell DT90E Thermostat to replace my current dial operated Honeywell T40.

The wiring to the T40 is Red to terminal 1 and Black to terminal 3. The earth is not connected and has been cut and pushed out of the way.

After reading other threads on this site, concerning the wiring up of this Stat, Am I right in thinking that the Red wire should be connected to terminal A in the DT90E and the earth to terminal B with the black wire,which I'm assuming is neutral, being terminated.

Any advice will be much appreciated.
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Black in terminal 3 is switched live, not neutral.

Wire as -

Red to A
Black to B

Leave the earth out of the way.

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