Adjust the compressor-to-auxiliary heat delta. This is the primary fix.
- Navigate to MAIN MENU > SETTINGS > INSTALLATION SETTINGS > THRESHOLDS > CONFIGURE STAGING MANUALLY > COMP TO AUX DELTA.
- Increase the value. This setting defines how many degrees the indoor temperature can drop below the setpoint before auxiliary heat engages. A higher number gives your heat pump more time to work.
If that didn't work: Check the minimum outdoor temperature lockout.
- Go to MAIN MENU > SETTINGS > INSTALLATION SETTINGS > THRESHOLDS > COMPRESSOR MIN OUTDOOR TEMP.
- If set to a fixed temperature and it's colder outside, the heat pump is locked out. Set to 'Disabled' to maximize heat pump use.
Heads up: To prevent short cycling and improve efficiency, increase the HEAT DIFFERENTIAL TEMP in the same THRESHOLDS menu. This makes the system turn on for a larger temperature drop.