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42
Air Evacuation
Note on Adding Refrigerant
Some systems require additional charging depending on pipe lengths. The standard pipe length varies
according to local regulations. For example, in North America, the standard pipe length is 7.5m (25’).
In other areas, the standard pipe length is 5m (16‘). The refrigerant should be charged from the service
port on the outdoor unit’s low pressure valve. The additional refrigerant to be charged can be
calculated using the following formula:
CAUTION
DO NOT
mix refrigerant types.
Liquid Side Diameter
R32 :
(Total pipe length -
standard pipe length)x
12g(0.13oZ)/m(ft)
(Total pipe length -
standard pipe length)x
24g(0.26oZ)/m(ft)
(Total pipe length -
standard pipe length)x
40g(0.42oZ)/m(ft)
φ
6.35(1/4”)
φ
9.52(3/8”)
φ
12.7(1/2”)
R22
(orifice tube in the indoor unit):
(Total pipe length -
standard pipe length)x
30g (0.32oZ)/m(ft)
(Total pipe length -
standard pipe length)x
65g(0.69oZ)/m(ft)
(Total pipe length -
standard pipe length)x
115g(1.23oZ)/m(ft)
R22
(orifice tube in the outdoor unit):
(Total pipe length -
standard pipe length)
x15g(0.16oZ)/m(ft)
(Total pipe length -
standard pipe length)
x30(0.32oZ)/m(ft)
(Total pipe length -
standard pipe length)
x60g(0.64oZ)/m(ft)
(Total pipe length -
standard pipe length)
x65g(0.69oZ)/m(ft)
R410A:
(orifice tube in the indoor unit):
(Total pipe length -
standard pipe length)
x30g(0.32oZ)/m(ft)
(Total pipe length -
standard pipe length)
x65g(0.69oZ)/m(ft)
(Total pipe length -
standard pipe length)
x115g(1.23oZ)/m(ft)
R410A:
(orifice tube in the outdoor unit):
(Total pipe length -
standard pipe length)
x15g(0.16oZ)/m(ft)
(Total pipe length -
standard pipe length)
x30g(0.32oZ)/m(ft)
