Specifications

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(3) Air purging
To protect the global environment, use a vacuum pump that do not release flourocarbon gas into the atmosphere.
(a) Remove the cap on both gas and liquid sides before starting operation.
(b) After completing the operation, do not forget to tighten the cap (gas may leak).
(c) Conduct air purging for all connected indoor units.
(2) Connection
Indoor Outdoor
¡ Secure the nut with a specified tightening
torque to avoid any gas leaks.
¡ Secure the nut with a specified tightening
torque to avoid any gas leaks.
¡ When air purging with a vacuum pump,
secure the nut with a specified tightening
torque to avoid any gas leaks.
¡ When air purging with a refrigerant from
an outdoor unit, just temporarily secure the
nut.
¡ Specified tightening torques are as follows:
Liquid side (ø 6.35): 17mm in width across flat of the flare nut: 15.7-19.6 N·m (1.6-2.0 kgf·m)
Gas side (ø 9.52): 22mm in width across flat of the flare nut: 29.4-39.2 N·m (3.0-4.0 kgf·m)
Gas side (ø 12.7): 24mm in width across flat of the flare nut: 39.2-49.0 N·m (4.0-5.0 kgf·m)
Note: Fully open the service valves (on both liquid and gas sides) after completing air purging
Liquid side
Gas side
Liquid side
Gas side
(4) Additional refrigerant charge
(a) When the total refrigerant pipe length for all the rooms exceeds the length of the uncharged pipe (30m), additional
refrigerant is required.
(If 30m or less, additional charge is not required.)
(b) For this multi type room air conditioner, it is not necessary to charge the refrigerant for the total maximum length in
all the rooms.
*1: Charge amount at the time of shipment.
*2: Maximum charge amount of the refrigerant (additional charge of 200g on site).
(c) Ensure that there are no gas leaks from the pipe joints by using a leak detector or soap water.
Procedure
1 Secure all flare nuts on both indoor and outdoor sides to prevent leaks from the
pipes.
2 Connect the service valves, charge hose, manifold valve and vacuum pump as
shown in the right figure.
3 Fully open the handle Lo for the manifold valve, and pump a vacuum for 15
minutes. Ensure that the meter is indicating -0.1 MPa (-76cmHg).
4 After vacuuming, fully open the operational valve (both liquid and gas sides)
with a hexagon wrench.
5 Ensure that there are no gas leaks from the joints in the indoor and outdoor units.
6 Repeat the above steps 1 ~ 5 for all connected indoor units.
Open
Open
Vacuum pump
Charge hose
Charge hose
Handle Lo
Handle Hi
Manifold
valve
Pressure
gauge
Compound
pressure
gauge
-0.1 MPa
(-76cmHg)
Model
SCM68ZA
SCM68YA
Charged pipe length
(Amount of uncharged
refrigerant) *1
30m (1950g)
Maximum total pipe length for all rooms
(Maximum amount of refrigerant) *2
40m (2150g)
On site additional charge
20g/m