Heat pumps don’t behave like furnaces. A furnace blasts hot air in short bursts; a heat pump delivers gentler heat over longer stretches. In a Chicago cold snap, running most of the day can be completely normal.
When it’s normal
- Outdoor temperatures are well below freezing.
- The house is holding its set temperature.
- You have a variable-speed model, which is designed to run at low output for long periods.
- It periodically pauses to defrost, sometimes with steam rising from the outdoor unit.
When it’s a problem
The house won’t reach the set temperature
If it runs constantly and the house stays cold on a mild day, the heat pump may be low on refrigerant, undersized, or have a failing component.
The outdoor unit is encased in ice
Light frost is normal. A solid block of ice means the defrost cycle isn’t working or water isn’t draining, and the unit can’t pull heat from the air.
Backup heat running all the time
Electric backup strips use a lot of power. If they’re on constantly, the heat pump isn’t doing its share, or the thermostat is set up to call for backup too readily.
Large setbacks
Turning the thermostat way down at night and back up in the morning makes a heat pump run hard and often triggers backup heat. Small setbacks or a steady setting usually work better.
What you can check
- Replace the filter.
- Clear snow and ice from around the outdoor unit (gently, without chipping at the coil).
- Make sure the thermostat is in heat mode, not emergency heat.
If the house stays cold or the unit keeps icing up, call (312) 924-7223 for heat pump repair in Chicago.