Heil communicating system shows E6; indoor blower runs but outdoor unit does not start

Safety first: Shut off power at the outdoor disconnect and verify with a meter. Capacitors can hold a charge; discharge properly before handling.

• Step 1 – Listen for contactor pull-in: With power on and a call for cooling, you should hear a click from the outdoor unit. If not, the contactor coil may not be energized or is defective.
• Step 2 – Inspect contactor: With power off, remove the service panel and inspect the contactor for burnt or pitted contacts. Replace if heavily worn or if the coil is open.
• Step 3 – Test capacitor: Remove and test the dual run capacitor (for compressor and fan) with a capacitance meter. Replace if more than ±10% out of rating or if bulged/leaking.
• Step 4 – Check wiring lugs: Tighten all high-voltage lugs on the contactor and compressor terminals. Look for signs of overheating or melted insulation.
• Step 5 – Compressor evaluation: If the contactor and capacitor are good but the compressor hums and trips, the compressor may be locked or failing and requires professional diagnosis.