Installation Guide

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Unit Installation
WARNING
1. High and low voltage wires should be led through different rubber rings of the electric box
cover.
2. Do not bundle the temperature controller wires or lay them side by side, otherwise errors will
occur.
3. High and low voltage wires should be secured separately. Secure the former ones with large
clamps and the latter ones with small clamps.
4. Use screws to tighten the power cord and signal wire of the units on the terminal board.
Improper connection may create a fire hazard.
5. If the power cord and communication wire are not correctly connected, the air conditioner
may suffer damage.
6. Ground the units by connecting the ground wire.
7. The units should comply with applicable local and national rules and regulations on power
consumption.
8. When connecting the power cord, make sure the phase sequence of the power supply
matches with the corresponding terminals, otherwise the compressor will get reversed and
operate abnormally.
Electrical Connection
Connecting the Power Cord & Communication Wire
Electrical wiring of Single-phase unit: MDUI18048/MDUI18060
Fig. 2.13
Terminals
Code
Remarks
Y
To a contact to control compressor
B
To a contact to control the 4way valve. It is suitable for
four way valve working in heating mode.
W1 To a contact to control the auxiliary heater 1
R
24 Volt Emergency (hot)
C
24 Volt (Common)
G
To a AC contact to control the indoor unit fan