Air-source heat pump outdoor unit beside a house in the snow

Generic photo: PeterEastern · CC BY-SA 4.0

HVAC: which family is this outdoor unit?

Read the data plate, match badge, model prefix and serial style to one of the seven US residential families, and confirm with the indoor unit or the 'manufactured by' line. Once the family is known, use that family's quick sheets and code lists.

Cross-checked ~10 min easyBrands: All

Before you start

Read the plate without removing electrical covers; if you must open a cover, kill power at the disconnect and verify dead first.
Do not touch refrigerant service valves: sealed-system work is blocked (EPA 608).

Diagnostic steps

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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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