Panasonic CU-YL28HBE5 Service Manual page 51

• Refer to the following table for the tightening torques. Be
sure to use two spanners to tighten.
(If the nuts are overtightened, it may cause the flares to
break or leak.)
Flare nut fastening torque N•m {kgf•cm}
ø6.35mm 18 (180)
ø9.52mm 42 (430)
ø12.7mm 55 (560)
3. After piping connection has been completed, make sure
that the joint areas of the indoor and outdoor units are
free from gas leakage by the use of nitrogen, etc.
4. Air purge within connection piping shall be carried out by
evacuation.
5. Close the tube joining area with putty heat insulator (local
supply) without any gap as shown in right figure. (To
prevent insects or small animal entering.)
6. The cardboard must be removed before installation of
piping work.
10.2.9. Heat Insulation
Use a material with good heat-resistant
properties as the heat insulation for the pipes.
Be sure to insulate both the gas-side and
liquid-side pipes. If the pipes are not
adequately insulated, condensation or water
leakages may occur.
Charging With Refrigerant
• At the time of shipment from the factory, this unit is charged with enough refrigerant for an equivalent pipe length of 30m. If the
equivalent pipe length used will be 30m or less, no additional charging will be necessary.
• If the equivalent pipe length will be between 30 and 50m, charge with additional refrigerant according to the equivalent length
given in the table below.
- For standard type
Additional charging amount
0.05kg/m
• Pump down operation
• Operate the pump down according to the following procedures.
1. Confirm the valve on the liquid side and the gas side is surely open.
2. Press the PUMP DOWN switch on outdoor printed board for 1
second or more.
3. Shut the valve on the liquid side surely.
ø15.88mm 65 (660)
ø19.05mm 100 (1020)
Equivalent length
50m
Procedure
Liquid-side pipes
Gas-side pipes
Minimum length
7.5m
Perform the cooling operation for five minutes or more.
When the valve is shut halfway, the compressor is occasionally
damaged.
51
Material that can
withstand 120°C or
higher
Notes