Refrigerant Piping; Purging Air And Checking Gas Leakage - Daikin R410A Installation Manual

Outdoor Unit Installation
4.

Refrigerant piping.

CAUTION
1) Use the flare nut fixed to the main unit. (To prevent cracking of the flare nut by aged deterioration.)
2) To prevent gas leakage, apply refrigeration oil only to the inner surface of the flare. (Use refrigeration oil for R410A.)
3) Use torque wrenches when tightening the flare nuts to prevent damage to the flare nuts and gas leakage.
• Align the centres of both flares and tighten the flare nuts 3 or 4
turns by hand. Then tighten them fully with the torque wrenches.
32.7-39.9N m
(333-407kgf cm)
5.

Purging air and checking gas leakage.

• When piping work is completed, it is necessary to purge the air and check for gas leakage.
WARNING
1) Do not mix any substance other than the specified refrigerant (R410A) into the refrigeration cycle.
2) When refrigerant gas leaks occur, ventilate the room as soon and as much as possible.
3) R410A, as well as other refrigerants, should always be recovered and never be released directly into the environment.
4) Use a vacuum pump for R410A exclusively. 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) to operate the stop valve rod.
• All refrigerant pipe joints should be tightened with a torque wrench at the specified
tightening torque.
5
Flare nut tightening torque
Gas side Liquid side
3/8 inch 1/4 inch
14.2-17.2N m
(144-175kgf cm)
Do not apply refrigeration
oil to the outer surface.
Flare nut
Do not apply refrigeration
oil to the flare nut avoid
tightening with over torque.
Valve cap tightening torque
Gas side Liquid side
3/8 inch 1/4 inch
21.6-27.4N m 21.6-27.4N m
(220-280kgf cm) (220-280kgf cm)
Service port cap 10.8-14.7N m
tightening torque (110-150kgf cm)
Compound
pressure gauge
Gauge
manifold
Low-pressure
valve
Charging
hoses
Vacuum pump
adapter
[Apply oil]
Apply refrigeration oil to
the inner surface of the
flare.
Pressure
meter
Gas stop
valve
Valve caps
High-
pressure
valve
Service port
Vacuum pump
Liquid stop valve
■English