Fitting Honeywell DT90E in Place of old Dial Thermostat
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M_arnold218
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Fitting Honeywell DT90E in Place of old Dial Thermostat

Post by M_arnold218 » Wed Oct 30, 2019 5:32 pm

I have a dial thermostat with the following 3 wires (according to the connections in it): N, L also looped through to COM, ON (and no wire in OFF).

I'm not sure how these should connect to the DT90E A,B,C connections.

Help appreciated.

ericmark
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Re: Fitting Honeywell DT90E in Place of old Dial Thermostat

Post by ericmark » Thu Oct 31, 2019 1:56 pm

http://www.free-instruction-manuals.com ... 457920.pdf

It seems A = Com
B = NO
C = NC
So you only use A and B so make the neutral safe, and other two go to A and B and really does not matter if wrong way around.

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