Unit turns on but compressor does not start; only the fan runs and no cooling occurs.

Safety first: Unplug the unit. Compressor circuits carry high voltage and can be dangerous.

Steps:

• 1. Listen for sounds: When cooling is selected, listen for a click and a deeper humming sound from the compressor. A brief hum followed by a click may indicate a locked compressor or bad start device.
• 2. Check airflow and settings: Confirm the unit is set to Cool mode with a low enough temperature setpoint and that the fan is running.
• 3. Access compressor compartment: Remove the outer shell (window/through-the-wall) or rear panel (portable) to access the compressor area.
• 4. Inspect wiring: Verify that all wires to the compressor terminals, start relay/PTC, and capacitor are firmly connected and not burnt.
• 5. Replace start components: If the start relay or capacitor is visibly damaged or tests bad with a meter, replace with Koldfront-specified parts.
• 6. Professional diagnosis: If the compressor still will not start, a technician must check compressor windings and system pressures. Compressor replacement is not a DIY repair.