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3.
3
Purging air and checking gas leakage
When piping work is completed, it is necessary to purge the
air and check for gas leakage.
WARNING
Do not mix any substance other than the specified refrigerant
into the refrigeration cycle.
When refrigerant gas leaks occur, ventilate the room as soon as
possible.
The specified refrigerant should always be recovered and never
be released directly into the environment.
Use a vacuum pump for the specified refrigerant. Using the
same vacuum pump for different refrigerants may damage the
vacuum pump or the unit.
If using additional refrigerant, perform air purging from the
refrigerant pipes and indoor unit using a vacuum pump, then
charge additional refrigerant.
Use a hexagonal wrench(4mm/0.2in) to operate the stop valve
rod.
All refrigerant pipe joints should be tightened with a torque
wrench at the specified tightening torque.
1) Connect
the p
rojection side of charging hose (which comes from
the gauge
manifold) to gas stop valve's service port.
2) open gauge
fully the m
anifold's low-pressure valve (Lo) and
completely close its high-pressure valve (Hi)
(High-pressure valve subsequently requires no operation.)
3)
Perform
vacuum pumping and
pressure gauge reads -0.1MPa (-76cmHg).*1
4) Close
the gauge
manifold's low-pressure valve (Lo) and s
the v
acuum pump.
(
maintain
this state for a few minutes to make sure that the
compound pressure gauge pointer does not swing back.)*2
5) Remove caps from liquid stop valve and gas stop valve.
6) Turn the liquid stop valve's rod 90 degrees counterclockwise
with a hexagonal wrench to open valve.
Close it after 5 seconds, and check for gas leakage.
Using soapy water, check for gas leakage from
flare and outdoor unit's flare and valve rods.
After the check is complete, wipe all soapy water off.
7) Disconnect charging hose from gas stop valve's service port
then fully open liquid and gas stop valves.
(Do not attempt to turn valve rod byond its stop.)
8) Tighten valve caps and service port caps for the liquid and
gas stop valves with a torque wrench at the specified torques.
*1. Pipe length vs. Vacuum pump run time
ensure
that the compound
top
the
indoor unit's
Pipe length
Run time
*2. If the compound pressure gauge pointer swings back,
refrigerant may have water content or a loose pipe joint may
exist. Check all pipe joints and retighten nuts as needed,
then repeat steps 2) through 4).
3.
4
Additional refrigerant charge
CAUTION
Refrigerant may only be charged after performing the leak
test and the vacuum pumping.
Check the type of refrigerant
nameplate. Charging with an unsuitable refrigerant may
cause explosions and accidents, so always ensure that the
appropriate refrigerant is charged.
Refrigerant containers shall be opened slowly.
The outdoor unit is factory charged with refrigerant. Calculate the
added refrigerant according to the diameter and the length of the
liquid pipe of the outdoor unit/indoor unit connection.
Pipe length and refrigerant amount:
Connective
Air purging
pipe length
method
Less
Use vacuum
than
pump.
25ft/7.5m
Liquid side:
Use vacuum
R410A: (Pipe length-
More
pump.
than
25ft/7.5m
Liquid side:
R410A: (Pipe length-
Be sure to add the proper amount of additional refrigerant.
Failure to do so may result in reduced performance.
3.
5
Refrigerant pipi
1) Caution on the pipe handling
Protect the open end of the pipe against dust and moisture.
All pipe bends should be as gentle as possible. Use a pipe
bender for bending.
Rain
If no flare cap is
available, cover the
flare mouth with
tape to keep dirt or
water out.
13
Up to
49.2ft
/
15m
More than
Not less than 10 min
Not less than 15min
needed
on the machine
Additional amount of refrigerant to be charged
1/4in
/
6.35mm
25
(
7.5
))
x
0.16oz/ft
3/8in
/
9.52mm
25
(
7.5
))x
0.32oz/ft
ng
work
Be sure to
place a cap.
49.2ft
/
15m
(
15g/m
)
(
30g/m
)
Wall
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