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Air E
v
acuation
Note on Adding Refrigerant
Some systems require additional charging depending on pipe lengths. The standard
length is 25 ft (7.6m), add refrigerant for lengths beyond 25 ft (7.6m). The system
MUST be operating in cooling mode to add charge. The refrigerant should be charged
as liquid 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:
OPEN VALVE STEMS GENTLY
• When opening valve stems, turn the
hexagonal wrench until it hits against
the stopper. Do not try to force the
valve to open further.
• Ensure hexagonal wrench is inserted
to full depth of socket. Failure to do
so or use of stepped service valve tool
may result in stripped and unusable
socket.
CAUTION
DO NOT
mix refrigerant types.
Liquid Side Diameter
Ø9.52mm (3/8in)
R-410A:
(Metering device in the indoor unit):
(Total pipe length - standard pipe length)
x65g (0.69oZ)/m(ft)
R-410A:
(Metering device in the outdoor unit):
(Total pipe length - standard pipe length)
x30g (0.32oZ)/m(ft)
10. Watch the Pressure Gauge for one
minute to make sure that there is
no change in pressure. The Pressure
Gauge should read slightly higher
than atmospheric pressure.
11. Remove the charge hose from the
service port.
Flare nut
Cap
valve body
valve stem
12. Using hexagonal wrench, fully open
both the high pressure and low pressure
valves.
13. Tighten valve caps on all three valves
(service port, high pressure, low
pressure) by hand. You may tighten it
further using a torque wrench if needed.
Summary of Contents for 18K
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