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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)
Only for Australia models :
• This unit contains factory charged refrigerant covering 20m of refrigerant piping and additional
refrigerant charge on the installation site is not required for an installation with up to 20m
refrigerant piping. When refrigerant piping exceeds 20m, additionally charge an amount
calculated from the pipe length and the above table for the portion in excess of 20m.
• If an existing pipe system is used, a required refrigerant charge volume will vary depending on
the liquid pipe size.
Formula to calculate the volume of additional refrigerant required
:
Additional charge volume (kg) = { Main length (m) – Factory charged volume 20(m) } × 0.03(kg/m)
• Make sure to remove the additional refrigerant amount according to the nameplate rated
charge (under 5m refrigerant piping ) under market or government verification testing .