Hisense 2AMW-42U4RRA, Technical & Service Manual, Page: 49 / 80

10. PIPING WORK AND REFRIGERANT CHARGE
10.3 Air tight test
Do use nitrogen when performing air-tight test.
Connect the gauge manifold using charging hoses with a nitrogen cylinder to the check joints of
the liquid line and the gas line stop valves. Perform the air-tight test. Don't open the gas line stop
valves. Apply nitrogen gas pressure of 4.15MPa.Check for any gas leakage at the flare nut
connections, or brazed parts by gas leak detector or foaming agent. Gas pressure does not
decrease is OK. After the air tight test, release nitrogen gas.
10.4 Additional refrigerant charge
Although refrigerant has been charged into this unit, additional refrigerant charge is required
according to piping length.
•
The additional refrigerant precharge quantity should be determined and charged into the system
according to the following procedure.
•
Record the additional refrigerant quantity in order to facilitate maintenance and servicing activities.
Refrigerant charge before shipment (W0 (kg))
W0 is the outdoor unit refrigerant charge before shipment
；
Xg is additional refrigerant outdoor unit needed to charge according to piping length
during installation.
0-15m over 15m
12K/ 14K 950 0g
18K 1070 0g
21K/AMW3-24U4RFA 1450 0g
0-20m over 20m
27K 2200g 0g
36K 2200g 0g
Model
Refrigerant precharged
before shipment(W0(g))
Total refrigerant pipe length
Xg = 12g / m × (Total pipe length(m) -20)
Refrigerant precharged
before shipment(W0(g))
Model
Total refrigerant pipe length
Xg = 12g / m × (Total pipe length(m) -15)
AMW3-24U4RAA
1800 0g
0-25m over 25m
0g
Model
Refrigerant precharged
before shipment (W0(g))
Total refrigerant pipe length
Xg = 12g / m × (Total pipe length(m) -25) 42K 3000g
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