The past few weeks, it's been a little cool in our area! The past few days, I've noticed that one of our heat pumps seems to be running all the time. In the past three days, it's ran +/-48 hours. Below is some quick info of what I'm seeing (bullet version; with questions to follow.
Quick Info
Conditions
Unit(s) Performance
As I understand HVAC, the first stage heat pump should only heat about 15-25F above internal temps, maybe lower under very cold conditions. Based on this, my units seem to be working properly (68F + 20F = 88F +/-Cold factor).
My question:
1) Does the thermostat tell the heat strips to kick on or is that a function within the unit?
1b) if function of unit, should it have an external temp sensor in the heat pump itself?
1b) if thermostat, where is that setting in the omnistat? I've caught myself going into every menu, but could have very well overlooked it.
1) With the two electric-only heat pumps, should the heat strips kick on if it's below 35 degrees; like the gas switch over? They seem to only kick on when there is >2F heating difference
2) Other than energy consumption, is it normal for a heat pump to run almost all the time in this cold weather?
Quick Info
- New House, first winter; not sure what normal is! Previous houses were smaller/single electric-only heat pumps.
- 2 Heat Pumps (2 stage) with backup heat strips (3T upstairs/ 2T downstairs)
- 1 Heat Pump (2 stage) with backup dual fuel/gas (3T downstairs)
- 1 ER Temp/Humidity Sensor
Conditions
- Night temps have been 25-35F
- Day temps < 40F
- Thermostats are setpoints are 68/73 for downstairs; 69/74 for upstairs.
Unit(s) Performance
- Upstairs heat pump is up stairs and doesn't kick on that often...heat rises. Register heat is around 86F. (single arrow beside temp on thermostat)
- Downstairs dual fuel system is switching properly as it gets colder. Register heat is around 110F (on gas).
- Downstairs 2T heat pump is running all the time. Single stage register heat around 83F. (single arrow beside temp on thermostat)
- Note: When I force the heat strips to come on, by increasing the temp >2 degrees; second stage registers heat around 110F (noted double arrows beside temp on thermostat).
- This past summer, the house seemed to cool fine and as needed. No issues with air flow, etc.
As I understand HVAC, the first stage heat pump should only heat about 15-25F above internal temps, maybe lower under very cold conditions. Based on this, my units seem to be working properly (68F + 20F = 88F +/-Cold factor).
My question:
1) Does the thermostat tell the heat strips to kick on or is that a function within the unit?
1b) if function of unit, should it have an external temp sensor in the heat pump itself?
1b) if thermostat, where is that setting in the omnistat? I've caught myself going into every menu, but could have very well overlooked it.
1) With the two electric-only heat pumps, should the heat strips kick on if it's below 35 degrees; like the gas switch over? They seem to only kick on when there is >2F heating difference
2) Other than energy consumption, is it normal for a heat pump to run almost all the time in this cold weather?