AC blowing warm air — Hilversum, Noord-Holland

When your air conditioner runs but only blows warm or room-temperature air, the most common culprits are a dirty air filter restricting airflow, low refrigerant from a leak, a frozen evaporator coil, a failed compressor, or an incorrect thermostat setting. A clogged filter is the easiest DIY fix — replace it and wait 3–4 hours for a frozen coil to thaw. If the problem persists, the system likely has a refrigerant leak or a component failure that requires a certified HVAC technician. Refrigerant leaks require EPA-certified handling, and recharging without fixing the leak is both illegal and wasteful. Diagnosis costs $75–$200; common repairs range from $150 (capacitor) to $1,500+ (compressor replacement).