Field pattern: AC not cooling? Dirty condenser and failed capacitor before 'low refrigerant'
Weak cooling has cheap mechanical causes that look like a charge problem to a customer: a plugged condenser coil, a failed run capacitor or a slow outdoor fan. The wrong turn is adding refrigerant before checking airflow and the capacitor; that hides the real fault, and a system that is truly low has a leak that must be found by a certified technician.
Cross-checked ~60 min moderateBrands: All
Before you start
- Shut off the outdoor disconnect and the breaker, and verify zero voltage before opening the control panel
- Discharge capacitors before handling; they can hold a charge after power is off
- Refrigerant gauges, recovery, leak search and charging are BLOCKED for this guide: refer to an EPA 608-certified technician
- Live-voltage checks only with insulated probes, dry footing and one hand
Diagnostic steps
Unlock all 7 steps with expected values
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