Display shows E7; unit may not start compressor or may shut down shortly after starting.

Warning: Work around the compressor involves live voltage. Only perform checks you are comfortable with and always disconnect power before removing covers.

Basic checks:

• Unplug the unit and remove the rear or bottom access panel to expose the compressor compartment.
• Inspect the compressor start relay and overload device mounted on the compressor terminals. Look for signs of burning, cracking, or melted plastic.
• Remove the relay/overload assembly and gently shake it. If you hear loose rattling pieces, the relay is likely failed.
• Test the relay and overload with a multimeter for continuity according to Marvel specifications. Replace the start relay/overload kit if defective.
• Check the compressor windings for continuity and proper resistance between terminals (C‑R, C‑S, R‑S). An open winding or direct short to ground indicates a failed compressor.
• Verify that the unit is receiving proper line voltage at the power cord and at the compressor terminals when commanded on.
• Reassemble with a new Marvel‑approved start device if needed, restore power, and observe operation. If the compressor still hums and trips or does not start, the compressor itself may be locked and require professional replacement.