Installation Manual

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Page 20
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Indoor Unit
Installation
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 25 ft (7.5m).
In other areas, the standard pipe length is 16 ft (5m). 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.
ADDITIONAL REFRIGERANT PER PIPE LENGTH
Connective Pipe
Length (m)
Air Purging
Method
Additional Refrigerant
> Standard pipe
length
Vacuum Pump
Liquid Side: Ø 0.25” (6.35mm)
Liquid Side: Ø 0.375” (9.52mm)
R410A:
R410A:
(Pipe length – standard length) x 15g/m
(Pipe length – standard length) x 0.16oZ/ft
(Pipe length – standard length) x 30g/m
(Pipe length – standard length) x 0.32oZ/ft