AC Not Cooling

medium priority

Air conditioner runs but doesn't cool the house

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Understanding This Problem

When your AC runs but fails to cool your home, it can be frustrating and uncomfortable. This common issue has several potential causes, from simple fixes to more complex repairs.

Quick Answer

AC Not Cooling usually points to dirty or clogged air filter restricting airflow, low refrigerant due to leak, frozen evaporator coil. Start with the safe checks listed below, document what changed, and stop running the equipment if the symptom involves burning smells, gas odor, repeated breaker trips, ice, water damage, or unsafe operation.

Common Causes

Dirty or clogged air filter restricting airflow
Low refrigerant due to leak
Frozen evaporator coil
Dirty condenser coils
Faulty compressor
Thermostat issues
Blocked or closed vents
Undersized AC for space

What You Can Do

Replace air filter immediately
Check and open all supply vents
Clean outdoor condenser unit
Schedule professional refrigerant check
Have technician inspect coils and compressor

What to Document Before Scheduling

When ac not cooling started and whether it happens during heating, cooling, startup, shutdown, or long cycles.
Thermostat setting, actual room temperature, filter condition, breaker status, and any error codes.
Photos or short videos of the thermostat, indoor unit, outdoor unit, vents, leaks, ice, or unusual sounds.
System age, brand, model number, recent maintenance, and any previous repair recommendations.

Prevention Tips

  • Change filters monthly during peak season
  • Schedule annual AC tune-up before summer
  • Keep outdoor unit clear of debris
  • Don't close more than 20% of vents

Questions Before Approving Repair

Which finding best explains ac not cooling, and what reading or observation supports it?
Can any safe homeowner step be tried first, or should the equipment stay off until inspection?
What is the difference between the immediate repair, follow-up maintenance, and replacement planning?
What parts, labor, exclusions, warranty assumptions, and safety risks should be written into the scope?
Medium Priority

Schedule service soon to prevent the problem from worsening.

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Services That Can Help

AC Repair

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AC Tune-Up

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Refrigerant Recharge

AC refrigerant leak repair and recharge.

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Related Cooling Issues

AC Blowing Warm Air

high

Air conditioner blows room temperature or warm air

AC Short Cycling

medium

AC turns on and off frequently without completing cooling cycle

AC Freezing Up

high

Ice forming on AC unit or indoor coil

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