Tighten screw terminals on all high-voltage and low-voltage electrical terminal blocks.
: Daisy-chain format only. T-tap or star configurations disrupt data packet delivery. Shielding Ground : Ground the shield layer (
When a fault occurs, the outdoor unit’s main PCB digital display or the indoor unit's wired controller will flash a specific alphanumeric code. Below are the most common critical codes found in the Midea V4 Plus service manual. Outdoor Unit Fault Codes Error Code Fault Description Immediate Checklist & Fixes Communication error between outdoor units
Outdoor DC fan motor failure, jammed blades, or inverter driver fault.
The EEV regulates refrigerant flow to individual indoor evaporators and outdoor sub-coolers. Power down the system. Unplug the EEV coil from the main board. midea vrf v4 plus service manual
Open or short circuit in outdoor ambient (T4) or condenser pipe (T3) thermistor. Measure sensor resistance. Cross-reference with standard at 25°C temperature chart. Voltage protection error Supply voltage fluctuates outside of nominal rating (380V-415V 3-Phase).
If an indoor unit is blowing warm air during cooling mode, or freezing up when it should be off, the EEV may be stuck. Disconnect the EEV coil from the PCB.
[Outdoor Unit Master] --(P Q E)-- [Indoor Unit 1] --(P Q E)-- [Indoor Unit 2] --(P Q E)-- [Indoor Unit 3] | (H1 H2 E) [Outdoor Unit Slave] Critical Wiring Rules:
Verify liquid and gas service valves are fully open. Check for overcharging, condenser fouling, or failed outdoor fan. Low Pressure Protection Tighten screw terminals on all high-voltage and low-voltage
Pull a second vacuum down to 1500 microns; hold for 30 minutes.
Indoor Unit Address Conflict. Cause: Duplicate address settings.
represents the total length of each liquid pipe size in meters. Indoor Unit Addressing Addresses can be assigned automatically or manually.
Verify that only one module is set to "0" on rotary switch ENC1. High pressure protection High-pressure switch open ( / 638 PSI). Shielding Ground : Ground the shield layer (
In a multi-module system, if one unit fails, another unit can act as a backup, ensuring continuous service. 5. Summary
175 meters between the outdoor unit and the farthest indoor unit.
Detailed diagrams for branch pipe connections, oil traps, and refrigerant charge calculations.
