1 Reply Latest reply: Mar 9, 2013 8:42 AM by MOD-Rhiana RSS

Aux heat VS Emergency heat ?

New Nester

I just installed my Nest thermostat but I'm confused between Aux heat (W2) and Emergency heat (*).

Which one should I choose ?

All I have is a one stage heat pump (cooling and heating) and an electrical heating element inside my furnace which I want to turn ON when it is too cold outside.  I don't want the heat pump to be turned On automaticaly when it is so cold outside.


Please help ! 

  • Re: Aux heat VS Emergency heat ?
    Nest Employee

    Hi Gates,


    If your heat strips are actually part of a separate furnace, you’ll need to make sure your Nest is set up as a dual fuel system. You’ll want to contact a Nest Certified Tech to make sure your dual fuel system is set up correctly.


    If your heat strips are part of your heat pump, you’ll want to plug that wire into the W2/AUX terminal. You can make sure your heat pump compressor doesn’t turn on when it’s cold in Settings under Equipment. Here’s how:

    • Press the ring to access the Nest menu
    • Select SETTINGS
    • Turn to EQUIPMENT and press to select
    • Press CONTINUE through your wiring setup and select HEAT PUMP
    • Confirm your heat pump orientation (your current orientation should be highlighted)
    • Select your compressor lockout temperature



    Rhiana B.