Kaisai 06RY1, Service Manual

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M thermal Mono
12 202008
Midea
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Key components:
1.
Accumulator:
Stores liquid refrigerant and oil to protect compressor from liquid hammering.
2.
Electronic expansion valve (EXV):
Controls refrigerant flow and reduces refrigerant pressure.
3.
Four-way valve:
Controls refrigerant flow direction. Closed in cooling mode and open in heating mode. When closed, the air side heat
exchanger functions as a condenser and water side heat exchanger functions as an evaporator; when open, the air
side heat exchanger functions as an evaporator and water side heat exchanger function as a condenser.
4.
High and low pressure switches:
Regulate refrigerant system pressure. When refrigerant system pressure rises above the upper limit or falls below the
lower limit, the high or low pressure switches turn off, stopping the compressor.
5.
Air purge valve:
Automatically removes air from the water circuit.
6.
Safety valve:
Prevents excessive water pressure by opening at 43.5 psi (3 bar) and discharging water from the water circuit.
7.
Expansion vessel:
Balances water system pressure. (Expansion vessel volume: 8L)
8.
Water flow switch:
Detects water flow rate to protect compressor and water pump in the event of insufficient water flow.
9.
Backup heater:
Provides additional heating capacity when the heating capacity of the heat pump is insufficient due to very low
outdoor temperature. Also protects the external water piping from freezing.
10.
Water pump:
Circulates water in the water circuit.
Midea CAC Confidential
M thermal Mono
202008 13
Part
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3 Refrigerant Flow Diagrams
Heating and domestic hot water operation(4,6KW for example)
Figure 2-3.1: Refrigerant flow during heating or domestic hot water operation
Cooling and defrosting operation(4,6KW for example)
Figure 2-3.2: Refrigerant flow during cooling and defrosting operations
Midea CAC Confidential
Mono