Air Handlers
NOTE: Y means Compressor control signal for the outdoor unit;
B which is energized under the heating mode means 4-way valve control
signal;
D means defrosting signal;
R means 24V AC power supply;
C means 24V common;
G means indoor unit fan signal for the indoor unit;
W1 means heater control signal.
NOTE: For cooling only unit, there is no need to connect the B and D
terminals.
NOTE: When outdoor defrosts, D of outdoor unit will send 24V signal to avoid
cold winds.
NOTE: When the electric heating operate, the indoor unit is forced to open the
indoor unit fan.
①. High and low voltage wires should be led through different rubber rings of the
electric box cover.
②. Do not bundle up the thermostat 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 big clamps and the latter ones with small clamps.
④. Use screws to tighten up the thermostat wires and power cords of unit on the
terminal board. Wrong connection may lead to fire hazard.
⑤. If the thermostat wires of unit and power cords are not correctly connected, the
air conditioner may get damaged.
⑥. Ground the unit through 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 cords, make sure the phase sequence of the
power supply matches with the corresponding terminals, otherwise the
compressor will get reversed and operate abnormally.
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