-
72
-
Operation valve
size (mm)
ø9.52 (3/8")
ø15.88 (5/8")
Tightening
torque (N·m)
34~42
68~82
Tightening
angle (
°
)
30~45
15~20
Recommended length
of a tool handle (mm)
200
300
Do not hold the valve cap area with a spanner.
Please use a torque wrench. If a torque wrench is not
available, fasten the flare nut manually first and then
tighten it further, using the left table as a guide.
10) Tighten a flare joint securely with a double spanner.
a) Do not apply force beyond proper fastening torque in tightening the flare nut.
b) Fix both liquid and gas service valves at the valve main bodies as illustrated on the lower, and then
fasten them, applying appropriate fastening torque.
(c)
How to remove the side cover Unscrew a screw from the side cover
(d)
Refrigerant pipe connection
●
Install a pipe carefully so that it may not touch the unit’s internal components.
●
A pipe touching with an internal component can generate abnormal noises or vibrations.
Airtighteness test completed
Vacuuming begins
Vacuuming completed
Vacuum gauge check
When the vacuum gauge's needle pointer creeps up, there is moisture left in the system
or a leak. Pull air again after you have checked the system for a leak and rectified it. Use
a reverse flow stop adapter to prevent the vacuum pump's lubricant oil from flowing into
the refrigerant system.
Please run the vacuum pump for at
least one hour after the vacuum gauge
shows -101kPa or lower. (-755mmHg
or lower)
No increase in the reading of the
vacuum gauge's needle pointer.
(3)
Air tightness test and air purge
●
Always use a vacuum pump to purge air trapped within an indoor and the refrigerant piping.
(a)
Air tightness test
1) When all the flare nuts on both indoor and outdoor unit sides are fastened. Conduct an air-tightness test from the service
valves charge port with the outdoor unit service valves (on both liquid and gas sides) closed tightly to check whether the
system has no leaks.
2) Use nitrogen gas in the air-tightness test. Do not use gas other than nitrogen gas under any circumstances.
Conduct the air-tightness test by applying 4.15MPa (42kg/cm
3
G) of pressure.
3) Do not apply the specified pressure at once, but increase pressure gradually.
a) Raise the pressure to 0.5 MPa, and then stop. Leave it for five minutes to see if the pressure drops.
b) Then raise the pressure to 1.5 MPa, and stop. Leave it for five more minutes to see if the pressure drops.
c) Then raise the pressure to the specified level (4.15 MPa), and record the ambient temperature and the pressure.
d) If the pressure does not drop after the units is left for approximately one day, the airtighteness is acceptable.
When the ambient temperature changes 1˚C, the pressure also changes approximately 0.01 MPa. The pressure. if
changed, should be compensated for.
(b)
Air purge
When a vacuum air purge is completed, remove the valve rod cap nuts and open the service valves (both liquid and gas sides)
as illustrated below. After you have made sure that the valves are in the full-open position, tighten the cap nuts (for the valve
rads and charge ports).
Side cover
Fixing screw
⁄
Pipes can only be laid toward
the rear direction.