2 weeks ago
I recently had my heat pump replaced and had a couple HVAC techs out. All messed with the wiring and said the installer or last guy had it wrong. I think the first guy had it right, I had only one heating element setup and I had the option for Heat Pump Balance allowing me to run both the heat pump and electric strips when it got really cold. Now I only have the option for Alt heat.
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My system is all-electric with a single-stage heat pump and electric heat strips for backup heat. It has two zones, each with a Gen3 Nest Learning Thermostat. Currently, the Nest shows I have dual fuel Alternative Heat and Alternative Heat Stage 2 (Which I'm certain is incorrect). One technician fixed the wiring and said I didn't need either the black or white wire (I can't remember which) and set them both to the same W1/F connector in my zone controller. He then placed one of the wires in the * spot on the Nest. The Nest then recognized I had a single-fuel system, not a dual-fuel system, and allowed me to set up Heat Pump Balance.
Right now, it's 18°F outside, and my system is running on heat strips. Anyone able to verify if I should have heat pump balance as an option and how I should correct the wiring to fix this?
Answered! Go to the Recommended Answer.
2 weeks ago
@Ben25 ,
It looks like you need some help understanding your new system with electric heat strips.
Whenever you have a heat pump, you can have alternate heat for those times it is so cold outside and your heat pump cannot keep up. In that case your thermostat can call for Auxiliary heat. The Auxiliary Heat is electric heat strips in the air handler. There is no thermostat control for nor does it know you have two 10kW heat strips.
When you see Emergency Heat, this is the same Heat Strips. The difference is when you have Emergency Heat the home owner can manually activate the heat strips. By giving the homeowner the ability to get some heat if the heat pump should fail and need repair in the winter time. This way you still have a way to have some heat so you don’t freeze out of your house while you wait for the repairman.
This is why the black wire and the White wire are on the W/E terminal in the zone controller.
On the Google Nest thermostat you should have the White wire on W2 and the Black Wire on *. Then define the * as Emergency Heat.
AC Cooling Wizard
AC Cooling Wizard
2 weeks ago
@Ben25 ,
It looks like you need some help understanding your new system with electric heat strips.
Whenever you have a heat pump, you can have alternate heat for those times it is so cold outside and your heat pump cannot keep up. In that case your thermostat can call for Auxiliary heat. The Auxiliary Heat is electric heat strips in the air handler. There is no thermostat control for nor does it know you have two 10kW heat strips.
When you see Emergency Heat, this is the same Heat Strips. The difference is when you have Emergency Heat the home owner can manually activate the heat strips. By giving the homeowner the ability to get some heat if the heat pump should fail and need repair in the winter time. This way you still have a way to have some heat so you don’t freeze out of your house while you wait for the repairman.
This is why the black wire and the White wire are on the W/E terminal in the zone controller.
On the Google Nest thermostat you should have the White wire on W2 and the Black Wire on *. Then define the * as Emergency Heat.
AC Cooling Wizard
AC Cooling Wizard
2 weeks ago
This is the exact answer I needed, this fixed my issue thank you @CoolingWizard!!
Just a note if anyone else comes across this, I did end up having to go into the "Pro setup" and select single fuel rather than dual fuel and confirm all the connections, but it popped up. I also swapped the power from Rh to Rc just because I noticed on my zone controller that what it was connected to, but it apparently doesn't matter.