Heat pump thermostat wiring help.

Old 08-13-16, 11:26 AM
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Heat pump thermostat wiring help.

Hello All,

I'm upgrading my Honeywell T8411R Heat Pump t-stat with an AprilAire 8466 and need some help with wiring. It is blowing warm air instead of cool air with the AprilAire t-stat installed.

1. On the original Honeywell (first image).
a. Green wire = G terminal. This should be the fan.
b. Brown wire = C terminal. This should be common.
c. Red wire = R terminal. This should be hot.
d. Yellow wire = connects to both W1 and Y terminals via jumper. This
seems odd given Y is typically for cooling and W is typically for
e. White wire = connects to both W2 and E terminals via jumper. This
should be secondary heating but I don't know what the E terminal is
f. Blue wire = O terminal. I'm not sure what the O terminal is for, secondary cooling??

2. On the AprilAire t-stat (second image). Note: I have it set to operate with Heat Pumps and I left the manufacture installed jumper between RC and R.

I wired it as follows.

a. Red wire = connects to both RC and R via jumper.
b. White wire = W terminal. This should be heating.
c. Yellow wire = Y terminal. This should be cooling.
d. Green wire = G terminal. This should be the Fan.
e. Brown wire = C terminal. This should be the common.
f. Blue wire = I didn't connect this wire to anything.

Apparently the O terminal is supposed to be for cooling also, which is the blue wire, but where would I hook it given the Yellow wire is in the W spot already? Would the blue wire go to the W2 spot on the AprilAire? Would everything seem correct in that case? What about the jumpers used in the original hookup (W1/Y and W2/E)?

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Old 08-13-16, 12:28 PM
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The wire on O/B activates the reversing valve in order to get A/C.
When not activated you get heat from the heat pump.

These two steps are mandatory.... the rest of the programming steps are incidental.
00- set equipment type jumper on back of stat to HP
02 - set to 1

should be set to default 0

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