B-30
INST
ALLA
TION PROCEDURE
600
o
600
CEILING
CASSETTE
CEILING CASSETTE
S series
5. Refrigerant piping work
5.4. Pipe connection (Fig. 5-8)
Indoor unit
1) When using commercially available copper pipes:
• Apply thin layer of refrigerant oil to pipe and joint seating surface before tightening
flare nut.
• Use two wrenches to tighten piping connections.
• Air-purge the refrigerant piping using your own refrigerant gas (don`t air-purge the
refrigerant charged in the outdoor unit).
• Use leak detector or soapy water to check for gas leaks after connections are com-
pleted.
• Use refrigerant piping insulation provided to insulate indoor unit connections. Insu-
late carefully following shown below.
2) Heat insulation for refrigerant pipes:
Wrap the enclosed large-sized pipe cover around the gas pipe, making sure that
the end of the pipe cover touches the side of the unit.
Wrap the enclosed small-sized pipe cover around the liquid pipe, making sure
that the end of the pipe cover touches the side of the unit.
Secure both ends of each pipe cover with the enclosed bands. (Attach the bands
20 mm from the ends of the pipe cover.)
See that stop valve on outdoor unit is fully shut (unit is shipped with valve shut). After
all piping connections between indoor and outdoor unit have been completed, vacuum-
purge air from system through the service port for the stop valve on the outdoor unit.
After completing procedures above, open outdoor unit stop valves stem fully. This
completes connection of refrigerant circuit between indoor and outdoor units. Stop
valve instructions are marked on outdoor unit.
• Apply a thin coat of refrigeration oil on the seat surface of pipe. (Fig. 5-9)
• For connection first align the center, then tighten the first 3 to 4 turns of flare nut.
• Use tightening torque table below as a guideline for indoor unit side union joint
section, and tighten using two wrenches. Excessive tightening damages the flare
section.
Copper pipe O.D.
Flare nut O.D.
Tightening torque
(mm)
(mm)
(N·m)
:
6.35
17
14 - 18
:
9.52
22
34 - 42
:
12.7
26
49 - 61
Warning:
Be careful of flying flare nut! (Internally pressurized)
Remove the flare nut as follows:
1. Loosen the nut until you hear a hissing noise.
2. Do not remove the nut until the gas has been completely released (i.e., hiss-
ing noise stops).
3. Check that the gas has been completely released, and then remove the nut.
Fig. 5-8
Refrigerant pipe and insulating material
(Procure locally)
Pipe cover (large) (Accessory)
Pipe cover
Refrigerant pipe (gas)
Refrigerant pipe (liquid)
Band (Accessory)
Cross-sectional view of connection
Refrigerant pipe
Insulating material
Squeeze
Fig. 5-9
6. Drainage piping work
Fig. 6-1
6.1. Drainage piping work (Fig. 6-1)
• Use VP25 (O. D.
:
32 PVC TUBE) for drain piping and provide 1/100 or more down-
ward slope.
• Be sure to connect the piping joints using a polyvinyl type adhesive.
• Observe the figure for piping work.
• Use the included drain hose to change the extraction direction.
Support metal
Air bleeder
Raised
Odor trap
Correct piping
Wrong piping
Insulation (9 mm or more)
O. D.
:
38 PVC TUBE for grouped piping
Downward slope (1/100 or more)
Grouped piping
O. D.
:
32 PVC TUBE
Make it as large as possible
Indoor unit
Make the piping size large for grouped piping.
Downward slope (1/100 or more)
(9 mm or more insulation)
Up to 500 mm
,
Max. 20m
1.5 - 2m
Max. 150 mm
