New nest thermostat wiring?

[Devdeech]

We just had a Nest thermostat put in our house a couple months ago and our electric bill has been through the roof since. We haven’t had a bill over $190 a month since we moved in 4 years ago and our last 2 electric bills have been over $400. I asked around and someone said our system could be going into defrost mode and if so Nest doesn’t recognize that it does and our emergency heat could be running? We have a heat pump. Not dual fuel. Electric back up heat. 

are the wires set up incorrectly? I can’t help but think it’s something within this thermostat making our electric bill skyrocket.

[Markjosephp]

Hello Devdeech,

I'm sorry to hear about the spike in your electric bills since installing the Nest thermostat. Based on your description, it could be worth checking the thermostat settings and wiring.

Firstly, ensure that the wiring is set up correctly. Mistakes in the wiring could lead to the system operating inefficiently or activating emergency heat unnecessarily. Regarding the possibility of the system going into defrost mode, it's crucial to check if the Nest Thermostat is compatible with your specific heat pump model. Some heat pumps operate differently, and if the thermostat is not fully compatible, it might not be effectively managing your system.

Additionally, you can review the Nest Thermostat settings to ensure they align with your HVAC system's requirements. Make sure the thermostat is set up to optimize energy efficiency and is not causing the emergency heat to run excessively.

If the issue persists, it might be helpful if you could share with us your old thermostat and Nest Thermostat's wiring setup.

Best regards,
Mark