Refrigerant Charge; Flaring And Flare Nut - Daikin SkyAir RZQ200 · 250C7Y1B Service Manual

SiBE26-701

1.3.4 Flaring and Flare Nut

Precautions for flaring
Specifications of flare nut

1.3.5 Refrigerant Charge

Troubleshooting
Ensure chamfering (filing). Furthermore, pay utmost care not to leave chips inside of piping.
Apply an appropriate coating of refrigeration machine oil to the inner and outer surfaces of
the flare nut to prevent any leaks. Furthermore, be sure to use synthetic oil (e.g. ether oil,
ester oil, alkylbenzene oil, or their mixed oil) as the refrigeration machine oil.
For flaring for R-410A units, the flare nut is changed from Class 1 Class 2 due to use of high-
pressure refrigerant. (Excessive fastening will result in cracks in the flare nut.)
A
For conventional flaring, a protrusion allowance of 0 to 0.5 mm was provided for piping. To
respond to the R-410A refrigerant, provide the allowance of 1.0 to 1.5 mm for the piping, and
then conduct flaring. (Only apply this method to the clutch type.)
The flare nut for R-410A is also changed from Class 1 Class 2 due to use of high-pressure
refrigerant.
Due to the change to Class 2, the flare nut outline of
torque remains unchanged.)
Use the flare nut that comes with the product.
Nominal size: 1/2", used
φ
for 12.7-mm piping
Nominal size: 5/8", used
φ
for 15.9-mm piping
Charge the new refrigerant in the liquid state through the service port of stop valve on the
liquid side (outdoor unit). Conduct vacuum drying using vacuum pump, and never conduct
flushing during refrigerant charging.
Pipe
diameter
Class 2 (R-410A) Class 1 (R-22, R-407C)
φ 6.4
8.7~9.1
φ 9.5
12.8~13.2
φ 12.7
16.2~16.6
φ 15.9
19.3~19.7
φ 19.1
(Reference) 24
φ
15.9 mm is changed. (The fastening
Maintenance Inspections
(mm)
A
9.0
13.0
16.2
19.4
23.7
81