Zahid Ali
4 min read · Air Conditioning
Check the Filter First
A severely clogged air filter restricts airflow to the point where the evaporator coil freezes over. When the coil freezes, no cooling happens — and the system may run continuously without lowering temperature. Check your filter: if it's grey and clogged, replace it, turn the system to fan-only for an hour to defrost the coil, then restart in cooling mode.
Check the Thermostat Settings
Confirm the thermostat is set to COOL and the set temperature is below the current room temperature. If it's set to HEAT or AUTO-HEAT, the system won't cool. If batteries are low, the thermostat may not be communicating correctly with the unit.
Check the Outdoor Unit
Go outside and look at the condenser unit. Is the fan running? Is there ice on the refrigerant lines? Is the unit surrounded by debris or vegetation? The condenser needs clear airflow on all sides. Ice on the lines almost always means a refrigerant issue or airflow problem that requires a technician.
What to Tell Us When You Call
If you've done the above and the system still isn't cooling: note the age of your system, the brand if you know it, what the thermostat reads versus what you've set it to, and whether the outdoor unit is running or not. This lets us arrive with the right parts and diagnose faster.
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