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.
