Page
11
Air
Evacuation
3.
Open the BLUE (Low Pressure) valve of Manifold
Gauge. Keep the RED (High Pressure) valve closed.
4.
Turn the vacuum pump ON to start evacuating the
air from the line set and indoor unit circuits.
5.
Run the vacuum pump for at least 15 minutes, or
until the Low Pressure Gauge reads -76cmHG
(-100 kPa or -30 In Hg). (Negative value)
6.
Close the Blue (Low Pressure) valve of Manifold
Gauge, then turn the vacuum pump OFF.
7.
Wait for 5 minutes, then check that there has
been no rise in Low Pressure Gauge reading.
8.
If there is a rise (Vacuum Loss), refer to the
Gas Leak Check section for information
on how to check for leaks. If there is no
change in vacuum reading, unscrew the cap
from the LIQUID Side Service Valve (Fig. 6.2)
9.
Insert a hexagonal wrench into the service valve
(LIQUID Side Valve), and open the valve by
turning the wrench in a 1/4 counterclockwise
turn. Listen for the sound of gas exiting the
system, then close the valve after 5 seconds.
10.
Watch the Pressure Gauge for a few minutes,
to make sure that there is no drop in the
pressure value (indicating a leak)
The Low Pressure Gauge should now show
a positive pressure value (Above Zero).
Flare Nut
Hexagonal
Dust Cap
Valve Core
11.
Remove the charging hose from the service port.
12.
Using a hexagonal wrench, fully open both the
LIQUID side and GAS side Service Calves.
13.
Tighten valve caps on all three valves (service
port, liquid side, gas side) by hand.
Then, tighten it further using a torque
wrench, if needed.
OPEN VALVE STEMS GENTLY
When opening valve stems, turn the hexagonal
wrench until it seats 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 (5m/~16’)
Vacuum Pump
Liquid Side: Ø 6.35 (ø 1/4”)
Gas side either
Ø 9.52 (ø 3/8”) or
Ø 12.7 (ø 1/2”)
Add for lengths beyond 5m (16 feet)
(Per additional meter) x 15g /m
(Per additional foot) x 0.16 oz/ft
CAUTION
DO NOT
mix refrigerant types. Be sure to use only the same type of refrigerant (R410a).
Fig. 6.2
Some systems require additional charging depending on pipe lengths. The pipe length varies according
to locations of the indoor and outdoor units. The system has been factory charged with sufficient R410a
refrigerant for the standard pipe length of 5m (~16‘). The additional refrigerant to be charged can be
calculated using the following formula. This is necessary only if the length exceeds 7.5m (25 feet).
Liquid Side: Ø 9.52 (ø 3/8”)
Gas side either
Ø 15.87 (ø 5/8”) or
Ø 19.05 (ø 3/4”)
Add for lengths beyond 5m (16 feet)
(Per additional foot) x 0.32 oz/ft
(Per additional meter) x 30 g/m
Copper Pipe from Indoor Unit
Service Port
(Only the GAS Side
Valve has this port)
