E5 error, compressor does not start or trips quickly, outdoor fan may run

Safety first: Shut OFF power at the outdoor disconnect and verify with a meter if you are qualified. Capacitors can retain charge; discharge properly before handling.

• Step 1 – Listen for compressor: When the unit is commanded ON, note whether you hear a brief hum then click (locked rotor) or no compressor sound at all.
• Step 2 – Inspect capacitor: With power OFF and panel removed, locate the dual run capacitor (often metal can with three terminals labeled C, FAN, HERM). Look for bulging top, oil leakage, or rust. Replace if any signs of failure are present.
• Step 3 – Check wiring connections: Verify all compressor and capacitor wires are tight and not burnt at the contactor or board.
• Step 4 – Measure supply voltage: If equipped and qualified, measure line voltage at the contactor. Low voltage under load can cause overcurrent trips; contact an electrician or utility if voltage is low.
• When to call a pro: If a new capacitor does not resolve E5, the compressor may be failing or shorted. Compressor diagnostics and replacement require a licensed HVAC technician.