Can I change wiring on Nest Learning from duel fuel option which negates heat pump balance feature

[rgaila]

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Original Poster: Christy Davy 8374 

Want to be able to use “heat pump balance’ feature on Nest Learning Thermostat, Gen. 3; had pro install it yesterday w/ 20+ year old Water Furnace geothermal heat pump w/ auxiliary back up electric strips. See that he wired it as dual fuel option, thus not showing/allowing ‘heat pump balance’ option as available. Isn’t this in error? This is not a duel fuel geothermal heat pump. Only back up electrical strips as auxillary. Can it be compatible/thermostat wired differently, so to use ‘heat pump balance’ option? Third picture is of the wiring of the Nest Learning Thermostat, done by a local pro installer.First picture is of the back/wiring side of the original Water Furnace Thermostat; 2nd picture is of the front of the old Water Furnace thermostat. Thank you for any advice.

[rgaila]

Hi Christy, 

Thanks for reaching out to us and welcome to our community! I'm happy to look into this for you. 

Here is what I found looking over your current wiring: 

• I can get why your pro wired it as a dual fuel system due to the presence of an Rc and Rh wire. In that case, each system can have its own thermostat or if a single thermostat is used for both systems there must be Rc and Rh terminations in the thermostat to keep the two control/transformers circuit(s) apart. However, since you know your HVAC to be geothermal/furnace, it could have led to the other conclusion below. 
• If you have wires in both the W1 and W2 connectors of your Nest thermostat, your system is a dual fuel system, and won’t use Heat Pump Balance. You can set a lockout temperature manually in the Equipment menu of your thermostat.

Unfortunately, I can only speculate as to why or how it was set up, but am unsure of how your specific HVAC system ultimately works. Our Compatibility Checker might provide some guidance; however, it seems best to reach out to that Nest Pro to report the malfunction and rearrange the wiring. 

My sincere apologies that I can't provide a clear-cut answer for your system. I hope your Nest Pro is able to see what's going on and rearrange your wiring to best suit your home. 

-From Ai, Community Specialist.