Microwave displays H1 and stops; may occur after long cooking times.

Safety Warning

This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.

If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.

Possible Causes

Blocked vents, failed cavity thermostat, cooling fan not running at full speed, excessive ambient temperature around unit

How to Fix / Troubleshooting

Safety first: Unplug the microwave and allow it to cool.

Ventilation:

Ensure there is adequate clearance around all vents (sides, rear, top). Move the microwave if necessary.
Clean dust and grease from vents with a vacuum or soft brush.

Usage:

Avoid running the microwave for extended periods at maximum power without breaks.
Do not operate the microwave empty; always have food or liquid inside.

If H1 recurs even with good ventilation and normal use, the cavity thermostat or cooling fan may be failing and should be checked and replaced by a technician.

Repair Difficulty

Hard 4/5

Required Part

Cavity Thermostat

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