Mitsubishi Electric CITY MULTI PQRY-P250 Installationshandbuch Seite 13

A Valve stem
[Fully closed at the factory, when connecting the piping, when evacuating,
and when charging additional refrigerant. Open fully after the operations
above are completed.]
B Stopper pin [Prevents the valve stem from turning 90° or more.]
C Packing (Accessory)
[Manufacturer: Nichiasu corporation]
[Type: T/#1991-NF]
D Connecting pipe (Accessory)
[Use packing and securely install this pipe to the valve flange so that gas
leakage will not occur. (Tightening torque: 250 kg-cm (25 N·m)) Coat both
surfaces of the packing with refrigerator oil (Ester oil, ether oil or
alkylbenzene [small amount]).]
E Open (Operate slowly)
F Cap, copper packing
[Remove the cap and operate the valve stem. Always reinstall the cap after
operation is completed. (Valve stem cap tightening torque: 250 kg-cm (25
N·m) or more)]
G Service port
[Use this port to evacuate the refrigerant piping and add an additional charge
at the site.
Open and close the port using a double-ended wrench.
Always reinstall the cap after operation is completed. (Service port cap
tightening torque: 140 kg-cm (14 N·m) or more)]
H Flare nut
[Tightening torque: 1200 kg-cm (120 N·m)
Loosen and tighten this nut using a double-ended wrench.
Coat the flare contact surface with refrigerator oil (Ester oil, ether oil or
alkylbenzene [small amount]).]
I ø19.05
J ø25.4 (PQRY-P200)
ø28.58 (PQRY-P250)
K Field piping
[Braze to the connecting pipe. (When brazing, use unoxidized brazing.)]
Appropriate tightening torque by torque wrench
Copper pipe external dia.
(mm)
ø6.35
ø9.52
ø12.7
ø15.88
ø19.05
Tightening angle standard
Pipe diameter (mm) Tightening angle (°)
ø6.35, ø9.52 60 to 90
ø12.7, ø15.88 30 to 60
ø19.05 20 to 35
Note:
If a torque wrench is not available, use the following method as a
standard.
When you tighten the flare nut with a wrench, you will reach a point
where the tightening torque will abrupt increase. Turn the flare nut
beyond this point by the angle shown in the table above.
Tightening torque
(kg-cm) (N·m)
140 to 180 14 to 18
350 to 420 35 to 42
500 to 575 50 to 57.5
750 to 800 75 to 80
1000 to 1400 100 to 140
Caution:
• Always remove the connecting pipe from the ball valve and braze
it outside the unit.
- Brazing the connecting pipe while it is installed will heat the ball
valve and cause trouble or gas leakage. The piping, etc. inside the
unit may also be burned.
• Use ester oil, ether oil or alkylbenzene (small amount) as the
refrigerator oil to coat flares and flange connections.
- The refrigerator oil will degrade if it is mixed with a large amount of
mineral oil.
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