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Digital Inverter
Installation Manual
9
EN-17
EN-18
*1
Use the vacuum pump, vacuum pump adapter, and gauge
manifold correctly referring to the manuals supplied with
each tool before using them.
Check that the vacuum pump oil is filled up to the specified
line of the oil gauge.
*2
When air is not charged, check again whether the connecting
port of the discharge hose, which has a projection to push
the valve core, is firmly connected to the charge port.
How to Open the Valve
Open or close the valve.
Liquid side
Open the valve with a 4 mm hexagon wrench.
Gas side
• While the valve is fully opened, after the screwdriver
has reached the stopper, do not apply torque
exceeding 5 N•m. Applying excessive torque may
damage the valve.
Valve handling precautions
• Open the valve stem until it strikes the stopper.
It is unnecessary to apply further force.
• Securely tighten the cap with a torque wrench.
Cap tightening torque
Insulating the Pipes
• The temperatures at both the liquid side and gas side
will be low during cooling so in order to prevent
condensation, be sure to insulate the pipes at both of
these sides.
• Insulate the pipes separately for the liquid side and
gas side.
• Insulate the branch pipes by following the instructions
in the installation manual provided with the branch
pipe kit.
• Use the insulating material provided as an accessory
to insulate the Ø19.1 mm pipe at the gas side.
• Seal the area where the Ø19.1 mm pipe and Ø22.2 to
Ø28.6 mm pipe are connected so that no gaps are left.
REQUIREMENT
Be sure to use an insulating material which can
withstand temperatures above 120°C for the gas side
pipe since this pipe will become very hot during heating
operations.
Valve unit
Charge port
Using a minus
screwdriver, turn it
counterclockwise by
90° until it hits the
stopper. (Full open)
Flare nut
Handle position
Closed completely
Opened fully
Main stopper
Movable part of valve (Stem)
Stopper pin
Valve size
Ø12.7 mm
50 to 62 N•m
(5.0 to 6.2 kgf•m)
Ø19.1 mm
20 to 25 N•m
(2.0 to 2.5 kgf•m)
Charge port
14 to 18 N•m
(1.4 to 1.8 kgf•m)
Replenishing Refrigerant
This model is a 30 m chargeless type that does not need
to have its refrigerant replenished for refrigerant pipes up
to 30 m. When a refrigerant pipe longer than 30 m is
used, add the specified amount of refrigerant.
Refrigerant replenishing procedure
1.
After vacuuming the refrigerant pipe, close the
valves and then charge the refrigerant while the air
conditioner is not working.
2.
When the refrigerant cannot be charged to the
specified amount, charge the required amount of
refrigerant from the charge port of the valve on the
gas side during cooling.
Requirement for replenishing refrigerant
Replenish liquid refrigerant.
When gaseous refrigerant is replenished, the refrigerant
composition varies, which disables normal operation.
Adding additional refrigerant
Formula for calculating the amount of additional refrigerant
(Formula will differ depending on the diameter of the liquid connecting side pipe.)
Single
Indoor Unit
Outdoor Unit
Figure of Single
Diameter of connecting pipe
(liquid side)
Amount of additional
refrigerant per meter (g/m)
Amount of additional refrigerant (g) =
Amount of refrigerant added for main pipe
D
Ø12.7
80
D u
( – 30)
