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

Field manual · Air Conditioner

GREE Sapphire and Livo wall-mount mini-splits (SAP, LIVS, LIVV, 4LIV, LIV...R32): quick sheet

Covers: GREE single-zone inverter heat pump wall-mount systems sold in the US. US model strings read as series + size + HP + voltage + 1 + revision letter, with AH = indoor head and AO = outdoor unit (for example SAP12HP230V1AH indoor + SAP12HP230V1AO outdoor). Series seen on GREE's US site: Sapphire (SAP09/12/18/24...HP230V1AH, R-410A) and Sapphire R32 (SAP...HP230V1R32AH); Livo GEN3 (LIVV09-36...HP230V1AH and LIVV09/12...HP115V1AH for 115 V); Livo GEN4 (4LIV05-24...HP230V1AH); Livo R32 (LIV05-36...HP230V1R32AH); older Livo LIVS...HP230V1B. Related GREE wall lines (Vireo 3VIR/VIR, Envo ENV) share the code scheme. The GWH12AWD... string named in some requests is a GREE factory/international model style and was not found in US listings: read the nameplate. Search terms: Gree Sapphire, SAP12HP230V1AH, SAP12HP230V1AO, Gree Livo, LIVV12HP230V1AH, 4LIV12HP230V1AH, Gree E6, E1, H5.

Cross-checkedBrands: Gree9 components

GREE wall-mounts are inverter heat pumps where the outdoor unit powers the indoor head through a 3-wire-plus-ground interconnect, and terminal 2 carries communication. Sapphire is GREE's high-efficiency, low-ambient line (listings agree on heating down to about -22 °F); Livo is the mid-range line and comes in 115 V and 230 V versions. Codes show as letters and digits on the indoor unit's display. GREE's own tech tip says E6 (communication) is the most common residential code and is usually wiring, not a board.

Safety first

  • All refrigerant work is blocked: refer to an EPA 608-certified technician.
  • Inverter DC bus capacitors stay charged for minutes after power-off; verify 0 V DC before touching the outdoor board.
  • Live communication-voltage tests are line-voltage work: use insulated probes and PPE.
  • Do not mix R-410A and R-32 indoor and outdoor units.

How it works

Line voltage goes to the outdoor unit. Terminals 1 and 3 carry power to the indoor head, terminal 2 is the communication line, plus ground. GREE says the interconnect should be 14 AWG, 4-conductor stranded, 600 V cable, grounded, with no splices; miswired accessories (condensate pump, float switch, disconnect) are a common source of E6.

The indoor board reads an indoor ambient sensor and an indoor coil (evaporator) sensor, runs a DC fan motor and louvers, and sends the call to the outdoor board, which drives the inverter compressor, outdoor fan, electronic expansion valve and reversing valve.

Outdoor protections stop the compressor and post a code: E1 high-pressure protection, E3 low-pressure protection, E5 over-current, H5 power-module (IPM) protection, U3 DC bus voltage drop, L9 power protection.

H1 is defrost status, not a fault: in heat mode the outdoor coil is defrosted periodically and the indoor fan pauses.

Components & tests

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Official manufacturer documentation

Always confirm values against the tech sheet for the exact model.

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. © 2026 OnCall Tech. Original content; not a reproduction of any manufacturer document.Generic part photos (not of this brand): Air-source heat pump outdoor unit beside a house in the snow by PeterEastern, CC BY-SA 4.0

Diagnostic guides for this appliance

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PTAC not heating (electric heat or heat pump)

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5 steps ~60 minmoderate
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PTAC error codes: how to read and clear them

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4 steps ~20 mineasy

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Trane XR14 / XR16 and American Standard Silver 14 / 16 outdoor AC and heat pumps (4TTR4, 4TTR6, 4TWR4, 4TWR6): quick sheet

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GREE Sapphire and Livo wall-mount mini-splits (SAP, LIVS, LIVV, 4LIV, LIV...R32): quick sheet · OnCall Tech