Smooth glass electric cooktop built into a wooden counter

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Heat pump outdoor coil iced over (not defrosting)

Light frost that clears every hour or so is normal. A solid block of ice means defrost isn't starting or finishing. Check outdoor fan, defrost sensor and board with a forced defrost before suspecting refrigerant.

Cross-checked ~60 min advancedBrands: All

Before you start

Switch to emergency heat while thawing so the outdoor unit is off.
Open disconnect and verify dead before working in the control box.
Never chip ice with tools.

Diagnostic steps

Unlock all 6 steps with expected values

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

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