Installation Manual
 Page 30  
3.  Open the Low Pressure side of the manifold 
gauge. Keep the High Pressure side closed.
4.  Turn on the vacuum pump to evacuate the 
system.
5.  Run the vacuum for at least 15 minutes, or 
until the Compound Meter reads -76cmHG 
(-10 Pa).
6.  Close the Low Pressure side of the manifold 
gauge, and turn off the vacuum pump.
7.  Wait for 5 minutes, then check that there 
has been no change in system pressure.
8.  If there is a change in system pressure, refer 
to Gas Leak Check section for information 
on how to check for leaks. If there is no 
change in system pressure, unscrew the cap 
from the packed valve (high pressure valve).
9.  Insert hexagonal wrench into the packed valve 
(high pressure valve) and open the valve by 
turning the wrench  in a 1/4 counterclockwise 
turn. Listen for gas to exit the system, then 
close the valve after 5 seconds.
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.
Flare nut
Cap
V
alve body
Valve stem
11.   Remove the charge hose from the service port.
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.
 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.
Note on Adding Refrigerant
ADDITIONAL REFRIGERANT PER PIPE LENGTH
Connective Pipe 
Length (m)
Air Purging 
Method
Additional Refrigerant
< Standard pipe length Vacuum Pump N/A
> Standard pipe
 length
Vacuum Pump
Liquid Side: Ø 6.35 (ø 0.25”)
R22: 
(Pipe length – standard length) x 30g/m 
(Pipe length – standard length) x 0.32oZ/ft
Inverter R410A: 
Fixed-frequency R410A: 
Inverter R410A: 
Fixed-frequency R410A: 
(Pipe length – standard length) x 15g/m
(Pipe length – standard length) x 0.16oZ/ft
(Pipe length – standard length) x 20g/m
(Pipe length – standard length) x 0.21oZ/ft
(Pipe length – standard length) x 40g/m
(Pipe length – standard length) x 0.42oZ/ft
Liquid Side: Ø 9.52 (ø 0.375”)
R22: 
(Pipe length – standard length) x 60g/m 
(Pipe length – standard length) x 0.64oZ/ft
(Pipe length – standard length) x 30g/m
(Pipe length – standard length) x 0.32oZ/ft
 CAUTION
DO NOT  mix refrigerant types.
Fig. 6.2
Air Evacuation
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 (25ft).
In other areas, the standard pipe length is 5m (16ft). The additional refrigerant to be charged can be 
calculated using the following formula: 
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