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View Full Version : New Honeywell thermostat wiring


dadakyleb
Nov 23, 2008, 08:22 PM
I am replacing my old Honeywell (q675 subbase) with a new Honewell FocusPro TH6220D.
I have a RUUD heatpump with a RUUD electric furnace.

It looks as though there are some wiring differences between the old and the new one.

The old thermostat had the following wires connected.

X (Brown) -- "Clogged filter switch or common connection"
E (White) -- "Emergency Heat Relay:
G (Green) -- "Fan Relay"
R (Red) -- "Power connection to transformer"
B (Blue) -- "Changeover Valve"
Y (Yellow) -- "Compressor Contactor"

The descriptions of the connections are from a manual for the q675 I found online.

Based on this I suspect that the connection is made in the following way on the new one.


Old Terminal Color New Terminal
X (Brown) C
E (White) E
G (Green) G
R (Red) R
B (Blue) G
Y (Yellow) Y

Does this look correct?

This basically means that the only change for honeywell was X is now C. I don't know if this is standardized in the HVAC world, or just a Honeywell terminal naming convention. In any case I have heard that if you miss wire these things it can cause major problems.

hvac1000
Nov 23, 2008, 09:32 PM
Looks good