Although you want your air conditioner to be cool, it is never a good thing for any part of a central air conditioning system to be frozen! There should never be ice on either the indoor or the outdoor unit, or on the connecting line-set. Occasionally, the indoor coil may ice up if the unit is operating at or in extremely cold temperature.
The minimum operating temperature of an air conditioner or heat pump is 70°F. In cases when air conditioning is required during cooler ambient temperatures, it is recommended that proper measures be taken to avoid freezing the system. Often, restaurants will install a ‘low ambient kit’ to allow for year-round operation without freeze up issues.
Often, when ice is visible on an air conditioning system, the problem must be resolved by Seattle A/C Service and Repair technicians. There is the occasional problem that can be solved by the homeowner/business owner:
- Dirty Air Filter — the air filter must be replaced. Regular visual inspection (once per month) will assure that the filter is always in peak condition.
- Vents — if the supply or return vents are closed, this can cause a problem with air flow that may cause freezing. Open all vents.
- Windows — running a central air conditioning system with windows open will place constant demand on the system, which can result in frozen lines or coils. Be certain that all window in the conditioned space are closed.
- Thermostat — be certain that the thermostat is set no lower than 70°F, or the system can eventually ice-up.
Issues that will require the diagnostic skills of Seattle A/C Service and Repair:
- Indoor Fan Motor — if motor is running slow, or not running, it must be repaired/replaced immediately
- Fan Belt — a loose or broken fan belt will render the fan idle, and must be replaced immediately
- Fan Relay — if the indoor fan relay is broken, it must be replaced immediately
- Blower Wheel — if the blower wheel is clogged or otherwise rendered inoperable, it must be serviced/replaced
- Refrigerant — the charge of the refrigerant may be low. A thorough inspection for leaks is indicated. Repairs and recharge of refrigerant as necessary.
- Restricted Air Flow — will not allow the cooled air to be circulated properly. The problem must be located and repaired.
- Capillary Tube/Orifice — any blockages found on inspection must be removed
- Expansion Valve — inoperable or faulty expansion valve must be repaired/replaced
- Contact — on the compressor, if the contact is stuck, it must be repaired/replaced
- Thermostat — if set above 70°F, the thermostat may be faulty and must be replaced
- Indoor Coil — if damaged or excessively dirty, the coil must be cleaned/repaired/replaced as indicated
Finally, the last item to check, if applicable is the whole house humidifier. If your system does include a humidifier, be certain to turn it off in months when using the air conditioner. Be certain to close any dampers associated with the humidifier as well.