Air Source Heat Pump Freezing Up
Our team receives frequent calls about refrigerated heat pumps. Although common, a heat pump freezing usually means that your system components are not functioning properly. Sometimes you can fix it yourself. But many times you need to call a heating, ventilation, and air conditioning (HVAC) professional like we do because the problem may require replacement parts or complex repairs.
Heat pump brain freeze
To help solve the problem, here are six common suspects that cause a heat pump to freeze:
1. Air filter clogged
When air filters take too long to collect particles, they can clog. This blocks airflow and traps moisture. Dust, pet dander, and smoke are just a few examples of possible clogging filters.
The National Air Filter Association (NAFA) recommends replacing your system's filters as soon as they become full of dust and debris. How quickly your filter clogs depends on many factors in your home. We recommend replacing the filter with a new one at least every three months.
Try changing the air filter, then running the unit's heat setting to melt the ice. If this does not resolve the issue, please contact one of our trained specialists for assistance.
2. Low or empty refrigerant
If your heat pump is running low on refrigerant, it could leak. This could be due to weak solder joints, faulty valves, or loose fittings. Also, when a part rubs against the refrigerant tank over time, it can eventually puncture it, causing it to freeze.
Take it easy and turn off the heat pump when the pipes start rattling. Then contact one of our HVAC specialists for an immediate inspection.
3. Dirty evaporator coils
The refrigerant flows through the evaporator coil of the heat pump. It transports heat into your Wrightsville home in cool weather and pulls it out in hot weather. When the coil gets dirty, its ability to transfer heat is compromised. Impaired airflow can cause freezing.
If you notice ice on the coil, turn off the heat pump. Then gently pour warm water over the coil to melt the ice. If your coil freezes again, please contact our team for assistance.
4. Faulty blower motor
If your blower motor isn't up to speed, it can wreak havoc on your system, causing it to freeze.
Fans may start and stop intermittently, run with reduced spin cycles, or not run at all. If this is the case, have it replaced by a professional contact us.
5. Dirty fan blades
When the fan blades of the blower become dirty, this affects the airflow and exhaust output of the system. Moisture can get trapped and turn into ice. If this happens, please call us to correct it as the fan blades are very fragile.
6. Winter Neglect
Depending on your heat pump model, some air source heat pumps (ASHPs) do not always operate efficiently in cooler temperatures. If this is a problem for your heat pump, ask one of our experts.
Also, the unit should be perfectly flush with the ground; any tilt will cause moisture to trap and freeze. If you think your heat pump is not level, please consult our HVAC professionals again.
Lastly, keep your equipment away from drains, as this can cause ice to form. In winter, be sure to check for ice buildup around or on the unit and remove it to prevent further problems.
Can I pour hot water on the heat pump?
Most heat pumps will have a defrost cycle that starts automatically, and you should never pour hot or cold water on appliances with electrical components. If you've checked your heat pump and found it's frozen, check that it's in defrost mode before trying anything else. It could be that the heat pump is already struggling with this.
If the defrost system isn't working, it could be a sign of a problem with the heat pump. You should call a qualified engineer to inspect the pump to see where the problem is.
Other online sources may suggest using tools to cull the ice rather than trying to melt it. However, in doing so, you may further damage the heat pump by denting or hitting critical components. We do not recommend trying to remove ice in this way.
Please contact us for any other heat pump questions.