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At some point all owners of air conditioning units will come across common problems with the operation of their unit. By following the proper Use and Care Instructions that accompany your Owner’s Manual you will greatly reduce the instances of issues.
However, should you happen to experience a blip in operations, the following list aims to address common problems, causes, and solutions for owners to try.
Common Problems: Air is not cooling enough:
1. Indoor airflow is not adequate
Check your furnace air filter to ensure it is clean and not dirty or clogged—this could be restricting air flow. Also make certain there is a proper supply of air coming through your home’s vents. Adjust all registers so they are open—if you find air not moving through all vents there may be a block in your duct work. These can be some common problems you run across.
2. A/C unit is not the correct size
An A/C unit that is too small will have continuous run cycles. An A/C unit that is too big will have short run cycles. Both of these issues will eventually cause your HVAC system to prematurely fail. Confirm you are using a unit that is the appropriate size for the space you are cooling by contacting an HVAC professional.
3. Outside compressor/condenser unit is obstructed
Remove any brush or debris from the area surrounding the unit—a good rule of thumb is to have nothing within 24”, including building walls and/or fences. Outside units require proper cool air flow in order to function correctly.
Common Problems: AC unit will not turn ON:
1. Power to unit is disconnected or loose
Locate the plug for the A/C unit and ensure it is properly plugged in to the electrical outlet. If power is not restored, check the building electrical panel to ensure a fuse has not blown, or a breaker tripped.
2. Blown fuse or tripped breaker
Replace the fuse or reset the breaker. If the fuse blows again, or the circuit breaker re-trips, leave it OFF.
3. Thermostat is not set correctly
Ensure the thermostat has working batteries and is operational. Turn your thermostat to its lowest temperature setting to see if the A/C unit turns ON. If your unit turns ON the temperature setting was set too high on your COOL setting. Set the temperature for lower than the actual room temperature is showing. If your unit does not turn ON there may be an issue with either your thermostat, or A/C unit.
AC unit is noisy:
1. Banging noise could mean a broken or loose part
Potentially a connecting rod, piston pin, or crankshaft inside the air compressor has broken or come loose, or possibly the compressor requires total replacement.
2. Humming due to loose or unattached parts
Loose parts, electrical issues, and loose wiring can all cause humming. To avoid damaging your A/C unit, turn the unit’s power OFF.
3. Screaming or loud whistling means a refrigerant leak or high pressure within the compressor
Immediately turn OFF the unit.
AC unit is leaking:
1. Overflow pan has a hole or crack
Check each corner and edge of the pan for a hole or crack—these can be repaired with an epoxy glue as a temporary fix. Damaged pans should be replaced.
2. Clogged filter
A dirty filter will cause ice to form on the unit’s evaporator coils-when it melts it will drip. Replace the filter and set a reminder to change it every 1-2 months while the A/C unit is in use.
3. Plugged condensate line
A plugged line will cause water to back up and fill the overflow pan. Try using a wet/dry vacuum, or a hand pump made for clearing A/C condensate lines, to suck or blow the line clear. To prevent build up from mildew or algae, pour a little bleach down the line every 4-6 months.These are examples of the most commonly experienced A/C unit problems by owners, and possible remedies. An HVAC professional can further troubleshoot and recommend corrective action or service should your problem persist. Contact a trusted local distributor to discuss any questions you may have concerning your A/C unit, or to learn about warranty coverage.