Gree / Mace H8

Gree / Mace error code H8 indicates: Gree-Mace G10 Inverter / Free Match / GMV5 / GMV6 Multi-VRF Commercial & Residential HVAC: Diagnostic fault code H8 registered by the microcomputer controller. Condensate drain collection pan overflow limit safety float switch open.

The primary root cause for Gree / Mace code H8 is: On Gree-Mace appliances engineered with Gree G10 Inverter low-frequency torque control, intelligent dual-stage rotary compressor, 46 Ω electronic expansion valve stepping motor coils, high-voltage PFC boost circuit (380V DC), and precision NTC thermistors (15 kΩ ambient, 20 kΩ coil, 50 kΩ discharge): indoor condensate collection tray overflow float switch open Metrological tolerance verification: float switch contacts closed (< 1.0 Ω) in normal down position; 230V AC pump coil ~180 Ω..

To resolve error code H8: Disconnect mains power before servicing. Unplug the harness at the main PCB and use a calibrated digital multimeter: clear drain pipe blockage and test float switch microswitch continuity. Inspect contacts for pin oxidation or loose terminals. Replace defective part if out of tolerance, re-energize and clear error: Using the remote controller: point at the unit and press 'LIGHT' 6 times in 3 seconds (or hold 'TURBO' + 'MODE' for 5 seconds) to enter diagnostic query mode. For inverter lockout errors (H5, HC, P0, P8, E6), switch off the external electrical isolator / circuit breaker for at least 3 minutes to allow DC bus capacitors to fully discharge.

Resetting power (unplugging for 5–10 minutes) clears temporary memory errors. However, if Gree / Mace code H8 persists, the physical component causing On Gree-Mace appliances engineered with Gree G10 Inverter low-frequency torque control, intelligent dual-stage rotary compressor, 46 Ω electronic expansion valve stepping motor coils, high-voltage PFC boost circuit (380V DC), and precision NTC thermistors (15 kΩ ambient, 20 kΩ coil, 50 kΩ discharge): indoor condensate collection tray overflow float switch open Metrological tolerance verification: float switch contacts closed (< 1.0 Ω) in normal down position; 230V AC pump coil ~180 Ω. must be inspected or replaced.

Set a digital multimeter to ohms (Ω). Disconnect power and test NTC Temperature Sensor Probe (Thermistor) across Across sensor pins 1-2 (unplugged harness). Expected nominal reading is 4.8kΩ–12kΩ (at 20°C–25°C). Tolerance: Negative temperature coefficient: resistance drops smoothly when warmed with fingers. OL = open circuit..

Standard electrical safety protocol: 1. Disconnect 230V mains power before opening panels. 2. Verify zero voltage at test points. 3. Allow hot water or heating elements to cool below 30°C before handling.