It's 95° out, the AC is running nonstop, and the house won't drop below 78. Before you book the $150–$250 'diagnostic visit,' work through the five causes that fix roughly half of all no-cool calls — none of which require a gauge set or a license.
Not sure this is your exact problem?Point your camera at it — SpotFix AI diagnoses it free in seconds, with a step-by-step AR guide for your exact model.
Scan It FreeA choked filter collapses airflow, freezes the coil, and mimics a refrigerant problem. If you can't see light through it, that may be your whole problem. Takes 2 minutes.
The air handler (inside) and condenser (outside) are on separate breakers. If the outdoor unit's breaker tripped, the fan inside blows room-temp air forever — the classic 'running but not cooling.'
Open the air handler area and check the copper lines and coil. Ice = shut the system off, run fan-only for 2–4 hours to thaw. Then fix the airflow cause (filter, vents) — if ice returns, it's low refrigerant and that's a pro visit.
Power off first. Years of cottonwood fluff and dirt insulate the coil so it can't dump heat. Gentle top-down rinse with a garden hose through the fins — you'll be shocked what comes out.
Trim shrubs, pull leaves off the fins, confirm the top fan spins freely and doesn't wobble.
Set to COOL, fan AUTO, 5° below room temp. Dying batteries or a thermostat baking in direct sun cause phantom 'AC problems' weekly. Scan the system with SpotFix AI — it checks symptoms against your model and tells you if what's left is a DIY fix or genuinely a refrigerant/compressor call.
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