I can see ice forming on my unit, is that normal?
Yes and no. If it is the outdoor section of a heat pump (in heating mode) then yes, frost will build up on the coil. The heat pump will initiate a defrost every 30,60, or 90 minutes to melt the ice.
If the system (any system) is operating in the cooling mode than no. The cooling should be switched off immediately to let the ice melt before a diagnosis can be completed. Some common causes for ice forming are a restricted air filter, bad blower motor, or low refrigerant charge. You can still run the indoor fan with the fan in the on position at your thermostat, this will help defrost the indoor coil. Lay some towels around the indoor section because as the ice melts it will likely leak out of the unit.
If your heat pump in heating mode continues to form ice and looks like a snowball then the defrost cycle has malfunctioned and it needs to be switched off as well. You can still operate the heat with the emergency heat setting at your thermostat until the outdoor unit is thawed and repaired.
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