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HomeRepair HelpHeil Central A/C RepairHeil Central air conditioner has poor temperature control Repair
Heil Central air conditioner has poor temperature control
If your Heil central air conditioner has poor temperature control, uneven cooling in the house, an AC temperature that is not accurate, or temperature swings, start with the air filter. A dirty or clogged air filter is the most likely cause because it restricts airflow through the furnace or air handler, reduces cooling capacity, and can cause the evaporator coil to frost over. Next, check the wall thermostat. Failed thermostat contacts can prevent the furnace or air handler and condensing unit from operating correctly or can cause the AC to cycle intermittently. Blocked or leaking vents can also create weak airflow and inconsistent room temperatures. An oversized air conditioner may cool quickly and shut off before conditioned air distributes evenly, leaving some rooms uncomfortable. Replace the air filter, inspect accessible vents, and use a multimeter to test thermostat continuity if you are comfortable doing so. Turn off power before servicing, and leave 240V components, the disconnect box, control board, and other line-voltage repairs to a qualified technician. Enter your Heil model number to find the exact air filter, thermostat, blower wheel, or other replacement part for your specific central air conditioner.
01 - Heil Central Air Conditioner Air Filter
Check and replace the air filter at least twice a year, more often in dusty/dirty environments or if there is a pet in the home. A clogged air filter will greatly reduce the air flow of the furnace or air handler which can result in poor temperature control when trying to heat or cool the home.
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Highly Likely
02 - Heil Central Air Conditioner Wall Thermostat
The wall thermostat has electrical contacts that control the power supply to the furnace or air handler and condensing unit. If the contacts in the thermostat fail, certain components of the cooling system may not work or may only work intermittently. To determine if the thermostat is defective, use a multimeter to test it for continuity. If the wall thermostat does not show proper continuity, replace it.
Common
03 - Heil Central Air Conditioner Wifi Thermostat
The WiFi thermostat has electrical contacts that control the power supply to the furnace or air handler and condensing unit . If the contacts in the thermostat fail, certain components of the cooling system may not work or may only work intermittently. To determine if the thermostat is defective, use a multimeter to test it for continuity. If the WiFi thermostat does not show proper continuity, replace it.
Common
04 - Clogged Air Filter
If the air filter is clogged, air cannot flow properly through the home's venting system. This greatly reduces the cooling capacity of the air conditioner. In addition, if the air filter is clogged, the evaporator coils will frost over and not be able to remove moisture from the air. The air filter should be checked and replaced at least twice a year, more often in dusty/dirty environments. Refer to owner's manual for guidance.
Less Common
05 - Blocked or leaking vents
The furnace or air handler must have good airflow to work properly. A blocked or leaking vent can prevent good air flow and cause inconsistent room temperatures.
Less Common
06 - Oversized air conditioner
An oversized furnace or air handler will quickly heat or cool the home and shut off. This causes acceptable temperatures in certain areas but not in others. The circulated air needs time to distribute evenly throughout the home; the air recirculating through the furnace or air handler for longer periods of time will produce better results.
Less Common
Frequently Asked Questions
Why does my Heil central air conditioner have poor temperature control?
Can a dirty air filter cause weak airflow and uneven cooling from my central air conditioner?
How do I know if my Heil wall thermostat is causing poor temperature control?
Why does my central air conditioner cool some rooms but not others?
How do I find the correct Heil central air conditioner replacement part?
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