This blog was originally published 3/8/2014.
Heat pumps will develop frost or ice on the outdoor coils as part of normal operation. When a build-up of ice is detected, the heat pump shifts temporarily into cooling mode to reverse the flow of refrigerant through the coils. Hot refrigerant moves through the outside coils, melting ice and defrosting the system. During the defrost cycle, supplemental heating units provide indoor heating. When the defrost cycle is complete, the unit shifts back to heating mode.
What Causes Your Heat Pump to Freeze Up?
If you have issues with your heat pump freezing up, it usually means a serious problem that should be addressed by an HVAC professional. If left unrepaired, the unit could suffer even more damage and eventually break down permanently. Your HVAC expert can address problems such as:
- Low refrigerant levels.
- Malfunctioning defrost controls.
- Bad defrost thermostats or sensors.
- Malfunctioning defrost relay.
- Sticking reversing valve.
- Damaged or malfunctioning outdoor fan motors.
- Need for elevation or leveling.
If your heat pump is completely covered with frost or ice, shut the system off and call your HVAC contractor for help. Some troubleshooting steps you can take before it reaches this point include:
- Check the unit’s air filter to make sure it’s not clogged or damaged. Replace dirty filters.
- Check indoor air vents and registers to make sure they are not blocked by boxes, furniture, clothing or other items.
- Clean away accumulations of leaves, grass, sticks, snow, dirt or other material that could be interfering with the unit’s airflow or blocking the outdoor coil.
- Check to make sure overflowing gutters are not dripping onto the outside unit.
Aqua Plumbing and Air serves HVAC and plumbing customers throughout Sarasota, Bradenton and Manatee County. Contact us today for more information on how to solve problems related to a heat pump freezing up and what to do to get the equipment working again. Call us at (941) 306-3715.
Written by John Miller
Image Provided by Shutterstock.com