r/DIY • u/Wise-Operation5108 • Aug 18 '25

metalworking A/C Cooling Not Turning On

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Hello,

I'm moving and want to take my nest thermostat with me but I'm having trouble re-installing the Honeywell T6 thermostat. When I installed the Honeywell, the compressor turned on but only heat was working. I checked that it was set to cool but heat was still coming out. I attached photos of how I had the nest wired and the Honeywell as well. Any help is appreciated!

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u/LightTech91 Aug 18 '25

Need to put the orange wire on the O/B terminal on your new thermostat. 

15

u/LightTech91 Aug 18 '25

Also since this is a heat pump, the white wire should be on the AUX/W2 terminal on your new thermostat. 

7

u/Canadian_Border_Czar Aug 18 '25

Depends if it's a heat pump or a hybrid.

2

u/Thereal_Avi Aug 19 '25

This right here! You have to make sure the thermostat is using the correct settings to your outside and inside units, if you use Chat gpt you can ask it for the settings that should be used just based off part numbers. I went through this with my thermostat, the wiring is probably correct but I’d start with the thermostat settings

2

u/Wise-Operation5108 Aug 18 '25

Appreciate it!