DIY HVAC Tools

Ruud mini split error codes

Ruud has sold ductless equipment from two makers. The Classic and Classic Plus lines (RIWH indoor / ROWH outdoor, sold by Ruud with a U prefix) are Fujitsu-built and use Fujitsu's two-digit code set, read from the wired controller display or from the indoor unit's lamp flashes. The Floating Air line, which Ruud added after acquiring Friedrich in 2023, is Gree-built and uses the Gree set. The model number on the indoor unit's label tells you which you have.

Covers: Classic and Classic Plus wall-mount (RIWH / ROWH / UIWH / UOWH), Endeavor Line multi-zone, Floating Air series (2023 and later).

Type it exactly as the unit shows it. Not sure which brand? It is printed on the front of the indoor unit.

Most looked-up Ruud codes

E:11Serial communication error between indoor and outdoor unitsE:41Indoor room temperature sensor fault (open or short circuit)E:63Inverter faultE6Communication error between indoor and outdoor unitsF1Indoor ambient (room) temperature sensor fault (open or short circuit)E1High pressure protectionH6Indoor fan motor not running (no feedback)

All Ruud codes

86 codes. Type to filter the list.

CodeMeaningTypeFix
E:11Serial communication error between indoor and outdoor unitsFaultDIY checks
E:12Communication error with the wired remote controllerFaultDIY checks
E:22Indoor unit capacity setting errorFaultDIY checks
E:23Indoor and outdoor unit combination errorFaultDIY checks
E:26Indoor unit address setting error (multi-split)FaultDIY checks
E:29Number of connected indoor units errorFaultDIY checks
E:32Indoor unit main board faultFaultTechnician
E:35Manual auto switch errorFaultDIY
E:41Indoor room temperature sensor fault (open or short circuit)FaultDIY checks
E:42Indoor heat exchanger (middle) temperature sensor fault (open or short circuit)FaultDIY checks
E:51Indoor fan motor faultFaultDIY checks
E:53Drain pump faultFaultDIY checks
E:62Outdoor unit main board fault (EEPROM)FaultTechnician
E:63Inverter faultFaultTechnician
E:65IPM (power module) faultProtectionTechnician
E:71Compressor discharge temperature sensor fault (open or short circuit)FaultDIY checks
E:72Compressor temperature sensor fault (open or short circuit)FaultDIY checks
E:73Outdoor heat exchanger (liquid) temperature sensor fault (open or short circuit)FaultDIY checks
E:74Outdoor air temperature sensor fault (open or short circuit)FaultDIY checks
E:75Suction gas temperature sensor fault (open or short circuit)FaultDIY checks
E:77Inverter heat sink temperature sensor faultFaultDIY checks
E:84Current sensor faultFaultTechnician
E:86Pressure sensor or pressure switch faultFaultTechnician
E:93Compressor start failureProtectionTechnician
E:94Compressor over-current tripProtectionTechnician
E:95Compressor motor control error (rotor position)ProtectionTechnician
E:97Outdoor fan motor faultFaultDIY checks
E:98Four-way (reversing) valve faultFaultTechnician
E:A1Discharge temperature too highProtectionDIY checks
E:A3Compressor temperature too highProtectionDIY checks
E:A5Low pressure protectionProtectionDIY checks
E1High pressure protectionProtectionDIY checks
E2Indoor anti-freeze protectionProtectionDIY
E3Low pressure protection (refrigerant shortage or blockage)ProtectionDIY checks
E4Compressor discharge temperature too highProtectionDIY checks
E5Over-current protectionProtectionDIY checks
E6Communication error between indoor and outdoor unitsFaultDIY checks
E7Mode conflict (multi-zone)ProtectionDIY
E8High temperature protection (overheating)ProtectionDIY checks
E9Indoor unit water-full (drain) protectionProtectionDIY
EEEEPROM (memory) error on a control boardFaultTechnician
FoRefrigerant recovery (pump-down) modeStatusDIY
F0Refrigerant shortage or system blockage detectedFaultDIY checks
F1Indoor ambient (room) temperature sensor fault (open or short circuit)FaultDIY checks
F2Indoor evaporator coil temperature sensor fault (open or short circuit)FaultDIY checks
F3Outdoor ambient temperature sensor fault (open or short circuit)FaultDIY checks
F4Outdoor condenser coil (middle) temperature sensor fault (open or short circuit)FaultDIY checks
F5Compressor discharge temperature sensor fault (open or short circuit)FaultDIY checks
F6Overload frequency limiting (protection)ProtectionDIY
F8Over-current frequency limiting (protection)ProtectionDIY
F9High discharge temperature frequency limiting (protection)ProtectionDIY
FHAnti-freeze frequency limiting (protection)ProtectionDIY
H1Defrost cycle runningStatusDIY
H3Compressor overload protectionProtectionDIY checks
H4System overload protectionProtectionDIY checks
H5IPM (inverter module) protectionProtectionTechnician
H6Indoor fan motor not running (no feedback)FaultDIY checks
H7Compressor desynchronization (loss of sync)ProtectionTechnician
HCPFC (power factor correction) protectionProtectionTechnician
U7Four-way (reversing) valve faultFaultTechnician
U8Indoor fan (PG motor) zero-crossing detection errorFaultDIY checks
C5Jumper cap malfunction (missing or wrong jumper)FaultDIY checks
PHDC bus high voltage (over-voltage) protectionProtectionDIY checks
PLDC bus low voltage (under-voltage) protectionProtectionDIY checks
LcCompressor start failureProtectionTechnician
LdCompressor phase loss or phase sequence errorProtectionTechnician
LECompressor stall (locked rotor)ProtectionTechnician
LPIndoor and outdoor unit mismatchFaultDIY checks
oEOutdoor unit fault (see outdoor board)FaultTechnician
U5Whole-unit current detection errorFaultTechnician
F7Oil return cycle (cooling)StatusDIY
LAOutdoor DC fan motor errorFaultDIY checks
LFCompressor over-speed protectionProtectionTechnician
P0IPM reset (drive module restarted)ProtectionTechnician
P5Compressor current protectionProtectionTechnician
P6Communication error between inverter drive and main controllerFaultTechnician
P7Inverter heat sink temperature sensor errorFaultDIY checks
P8Inverter heat sink (radiator) overheat protectionProtectionDIY checks
P9AC contactor protectionProtectionTechnician
PcCurrent sensor errorFaultTechnician
PdSensor connection protectionFaultTechnician
PETemperature drift protectionProtectionTechnician
PFDrive board ambient temperature sensor errorFaultDIY checks
PAAC current protectionProtectionDIY checks
PUCharging circuit errorFaultTechnician
PPAC input voltage anomalyProtectionDIY checks

How Ruud shows error codes

Classic / Classic Plus (RIWH / ROWH, Fujitsu-built): Units with a display show the code as E:xx (E:41). Wall units without one flash the Operation and Timer lamps: count the Operation flashes for the first digit and the Timer flashes for the second, so 4 Operation flashes then 1 Timer flash is E:41. A wired controller shows the code directly. 1x codes are communication faults, 2x are configuration and combination errors, 3x and 4x are indoor board, sensor and fan faults, 6x and 7x are outdoor board and sensor faults, 9x are compressor and fan faults, and Ax codes are temperature and pressure protections.

Floating Air series (Friedrich-built, Gree platform): The code shows on the indoor unit's display in place of the temperature. If the display is off, press the Light button on the remote. Some models also count out the code as indicator blinks. E codes are system protections and faults, F codes are mostly sensor faults, H codes are outdoor and compressor protections, U codes are motor and valve faults, and P codes are power-supply faults.

Brands built on the same platform

These brands share a code table with Ruud because the same factory builds them, so their pages describe the same faults: Arcoaire, Blueridge, Comfortmaker, Cooper & Hunter, Day & Night, Friedrich, Fujitsu, Gree, Heil, KeepRite, Rheem, Tempstar, Tosot, York.

Sources

  • Rheem RIWH / ROWH Ductless Design and Technical Manual (RIWH18ASJ to RIWH36AXJ)
  • Rheem Classic Series ductless installation manual 9318739237 (Fujitsu General document number)
  • Friedrich Floating Air Select Service and Parts Manual (2015-2019), diagnostic code table

Updated September 2026. Manufacturer site: www.ruud.com