Building facade with window and wall air conditioner units

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PTAC not cooling (fan runs, air not cold)

Most PTAC no-cool calls are airflow (filter, coils), a wrong control setting or a failed compressor start component. Rule those out before suspecting the sealed system.

Single source ~60 min moderateBrands: Amana, GE Zoneline, Friedrich, LG, All

Before you start

265/230 V or 208 V circuit: unplug the chassis or kill the breaker before opening it
Inverter and capacitor-start units hold dangerous voltage after power-off; wait the time on the label and verify 0 V DC before touching boards or capacitors
Sealed refrigerant system work (leak search, recharge, valves, compressor): refer to an EPA 608-certified technician. No procedure here.

Diagnostic steps

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