Kaisai 06RY1, Service Manual

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M thermal Mono
20 202008
Midea
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4.4 Four-way Valve Control
The four-way valve is used to change the direction of refrigerant flow through the water side heat exchanger in order to
switch between cooling and heating/DHW operations.
During heating and DHW operations, the four-way valve is on; during cooling and defrosting operations, the four-way
valve is off.
4.5 Electronic Expansion Valve Control
The position of the electronic expansion valve (EXV) is controlled in steps from 0 (fully closed) to 480 (fully open).

At power-on:

The EXV first closes fully, then moves to the standby position. After a few seconds the EXV moves to an initial
running position, which is determined according to operating mode and outdoor ambient temperature. After a
further a few minutes, the EXV is controlled according to suction superheat and discharge temperature. Once a
further a few minutes have elapsed, the EXV is then controlled according to suction superheat, discharge
temperature and compressor speed.

When the outdoor unit is in standby:

The EXV is at standby position.

When the outdoor unit stops:

The EXV first closes fully, then moves to the standby position.
4.6 Outdoor Fan Control
The speed of the outdoor unit fan(s) is adjusted in steps, as shown in Table 3-4.3.
Table 3-4.3: Outdoor fan speed steps
Fan speed index
Fan speed (rpm)
6kW 8-10kW 12-14kW 16kW
0 0 0 0 0
1 200 200 200 200
2 250 250 250 250
3 300 300 300 300
4 350 350 350 350
5 400 400 400 400
6 450 450 450 450
7 500 500 500 500
8 530 530 550 550
9 550 550 580 600
10 580 580 610 650
11 600 600 630 700
12 600 600 650 730
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