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AC not cooling
Your AC is running but the house isn't getting cooler. The cause is usually simple — and often fixable before you call a pro.
Before anything — check these
If any of these are true, stop and get professional help now:
- Ice on the refrigerant lines or indoor coil
- Burning smell or unusual noises
- Warm air even with a clean filter and correct settings
Answer a few questions
Your answers help narrow down the likely cause.
Is the air filter dirty or overdue for a change?
Is there ice or frost on the pipes or indoor coil?
Does the system run but blow warm air?
Is the outdoor unit not running at all?
Safe checks you can do
Tick what you've checked. Only do homeowner-safe actions.
Likely causes
| Cause | Likelihood | Severity | Cost |
|---|---|---|---|
| Dirty air filter | high | Low | $0–$25 |
| Low refrigerant / leak | medium | Medium | $200–$1,500 |
| AC capacitor or contactor | medium | Medium | $150–$400 |
| Thermostat issue | medium | Low | $50–$300 |
| Compressor failure | low | High | $1,500–$3,000 |
Recommended next action
If the filter is clean and settings are correct but it's still not cooling, book an AC service call. If you see ice, a burning smell, or hear loud noises, call an emergency HVAC technician now.
Related tools
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Emergency AC Repair — What To Do
Burning smells, no cooling in extreme heat, or a frozen system need fast, safe action. Here's exactly what to do first.
Plan the fix
Once you know roughly what's wrong, size the job and get a cost range:
HVAC System Planner