Gree GUD71W/NhA-T - “Lp” IDU and ODU Unmatched; “U7” 4-Way Valve Switch-Over Error

GREE U-Match 5 SERIES UNIT SERVICE MANUAL
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3.4.24 “Lp” IDU and ODU Unmatched
Error display: ODU mainboard, IDU wired controller and IDU receiver light board will display Lp
Error judgment condition and method:
Possible reason:
■Models of indoor unit and outdoor unit do not match with each other
Troubleshooting：
Turn off the unit and replace with a matched indoor or outdoor unit.
3.4.25 “U7” 4–Way Valve Switch-Over Error
Error display: ODU mainboard, IDU wired controller and IDU receiver light board will display U7
Error judgment condition and method:
Possible reason:
■Voltage is abnormal. For example, low voltage will cause abnormal direction change of the 4-way valve.
■Pilot valve holder hole or the capillary tube is blocked, which has caused small flow or no flow.
■Capillary tube is blocked when connecting to the pilot valve or main valve.
■Coil is not power-connected, or is open-circuited. Voltage is low, or the contact between turns or terminals is
bad.
■The stainless steel cover of pilot valve is damaged, or the steel core is stuck, or the spring is not elastic.
■Insert block is bent or not elastic, so the little slide cannot get in place.
■When adding refrigerant, the little slide is over-running and can’t spring back.
Troubleshooting：