From CoolAutomation Wiki
Jump to: navigation, search

Connecting to Midea VRF system

  • If CoolMasterNet is the only central controller in the system:

Outdoor Switch SW3-1 must be ON for proper operation of CoolMasterNet connected to XYE bus.

  • If two central controllers should be connected:


We recommend to connect to line L7 on CoolMasterNet. Lines L4, L5, L6 can also be used.

Auto Addressing Mode

For proper operation of the Central Controller (CoolMasterNet), it is important to have an Auto Addressing Mode turned ON on Outdoor PCB. This is done by setting S6 (on some models it is called NI_SD-AD_FD) DIP Switches to OFF-OFF-OFF positions like shown on the below picture. After that setting is done it is required to power reset the Outdoor unit.

Midea VRF Error Codes

Malfunction Code Problem
E0 Phase sequence disorder or loss of power phase 0x10 16
E1 Communication malfunction 0x11 17
E2 T1 sensor malfunction 0x12 18
E3 T2A sensor malfunction 0x13 19
E4 T2B sensor malfunction 0x14 20
E5 T3 or T4 sensor of discharge of compressor fails down 0x15 21
E6 Detection of current direction alternating is abnormal 0x16 22
E7 EEPROM error 0x17 23
E8 Fan speed is out of control 0x18 24
E9 Communication malfunction between main board and display board 0x19 25
EA Compressor Over-current (four times) 0x1A 26
EB Inverter module protection 0x1B 27
EC Cleaning malfunction 0x1C 28
ED Outdoor unit malfunction 0x1D 29
EE Water level detection malfunction 0x1E 30
EF Other malfunctions 0x1F 31
P0 Evaporator temperature protection 0x20 32
P1 Anti-cool or defrost protection 0x21 33
P2 Condenser high-temperature protection 0x22 34
P3 Compressor temperature protection 0x23 35
P4 Discharge pipe temperature protection 0x24 36
P5 Discharge high pressure protection 0x25 37
P6 Discharge low pressure protection 0x26 38
P7 Voltage of power supply is too high or too low protection 0x27 39
P8 Compressor over-current protection 0x28 40
P9 Reserved 0x29 41
PA 0x2A 42
PB 0x2B 43
PC 0x2C 44
PD 0x2D 45
PE 0x2E 46
PF 0x2F 47
00# Communication malfunction between NIM and main PCB 0x30 48
01# Communication malfunction between central controller and NIM 0x31 49
02# Communication malfunction between central controller and functional module 0x32 50
03# Communication malfunction between central controller and PC (gateway) 0x33 51
04# Control Operation denied 0x34 52
05# Control Operation timeout 0x35 53
06# Address does not exist 0x36 54
07# Unsupported Control Operation 0x37 55