Homeowner in Tomahawk, WI, troubleshooting why the home's heat pump is freezing up.

Our team at Premier Heating & Cooling gets calls about frozen heat pumps on a semi-regular basis. Though common, a freeze up usually means your system’s components aren’t working correctly. Sometimes you can fix it yourself. But oftentimes, you’ll need to call a professional, as it may call for a part replacement or complex repair.

To make the process easier, here are the six usual suspects causing heat pumps to freeze up:

  1. Clogged Air Filter
  2. When air filters are left to collect dust for too long, they become clogged. This hinders airflow, which can trap moisture, along with many other component problems. Try replacing your air filter, then running your unit’s heat setting to melt the ice. If that doesn’t work, contact a professional.

  3. Low or Empty Refrigerant
  4. If you’re low on refrigerant, this is indicative of a leak. When a component rubs against the refrigerant tank over time, it can eventually puncture it, leading to a freeze up. This could be a weakened solder joint, an opened valve, rattly pipes, or unsecured fittings. In this case, you should power down your heat pump and contact your technician for immediate inspection.

  5. Filthy Evaporator Coil
  6. Refrigerant flows through the evaporator coil. It transports heat into your home during cool weather and pulls it out during hot weather. When it becomes dirty, this impairs its ability to transfer heat. This can compromise airflow, leading to a freeze up. If you notice ice on your coils, power down your heat pump. Then gently attempt to remove the ice using a dull object. After removing the larger chunks, pour warm water over the coils to melt the remainders. If your coils freeze back up, call your HVAC technician.

  7. Faulty Blower Motor
  8. If your blower motor isn’t up to speed, it can wreck havoc on your system, leading to a freeze up. See if the exhaust fan is running properly. It may start and stop intermittently, run at a reduced spinning cycle, or not run at all. If this is the case, have a professional replace it.

  9. Dirty Fan Blades
  10. When the blower’s fan blades become dirty, this compromises the system’s airflow and exhaust output. Moisture will become trapped and turn into ice. If this happens, call an experienced technician to correct it, as the fan blades are very sensitive.

  11. Wintertime Neglect
  12. Remember, air-source heat pumps generally should not be operated in temperatures under 40 degrees Fahrenheit. The unit should be completely level with the ground; any tilting can cause moisture to get trapped and become frozen. Additionally, your unit should be away from gutter flow, as this can cause ice formation. During the winter, always check for ice accumulation on your unit, and clear it away to prevent further issues.

Experiencing a frozen heat pump? Premier Heating & Cooling’s team of experienced technicians is just around the corner in Tomahawk, WI, to assist you. Call us today at 715-453-4700, or schedule service online if you need a repair.

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Premier Heating and Cooling services residents in Arbor Vitae, Birnamwood, Brokaw, Harshaw, Hazelhurst, Irma, Merrill, Minocqua, Rhinelander, Rib Mountain, Tomahawk, Tripoli, Wausau, Weston, Woodruff, and surrounding Wisconsin communities. Visit our service area page to learn more. For service, call us now at 715-453-4700 or request service online today.