Haier AU282FHAHA Service Manual page 21

Installation procedure
IV Vacuumizing of the pipes and indoor unit (using vacuum pump to vacuumize, it is strictly
forbidden to use refrigerant purging)
Choose of vacuum pump: it shall choose those that can reach a good vacuity ( Lower 200Pa ) and
have a large air discharge amount (over 40L/min).
After finishing the airtight quality test and discharging the nitrogen, connect the instrumental
diverter to the 3-way discharge valve, then connect the vacuum pump according to the below figure.
If the hi-pressure valve of the outdoor unit is 3-way valve.
Indoor side
Fasten
Fasten
Indoor unit
When the hi-pressure valve of the outdoor unit is 2-way valve .
Indoor side
Joint
Joint
Indoor unit
When the hi-pressure valve of the outdoor unit is 2-way valve:
(1) Firstly connect indoor, outdoor power supplies, and communication lines, then set addresses
of indoor units and check their correctness.
(2) Determine running mode according to indoor temperature: Set to cooling mode when indoor
temperature Ta
(3) Keep stop valve of outdoor unit close , and start the indoor unit according to running mode
determined by indoor temperature.
Commercial Air Conditioner
Stop valve close
Outdoor side
Fasten
Fasten
Stop valve close
(Liquid side)
Outdoor side
Fasten
Fasten
2-way valve
(Liquid side)
23 set to heating mode when Ta<23 .
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Connection of pipes
Low pressure
meter
(Gas side)
Gas discharging valve
Gas discharging
valve
Vacuum pump
Outdoor unit
Low pressure
meter
3-way valve close
(Gas side)
Gas discharging valve
Vacuum pump
Outdoor unit
Model: AU282FHAHA
High pressure
meter
Instrument
VL VH
distributor
P
High pressure
meter
Instrument
VL VH
distributor
P