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3P362438-5N English
Precautions when knocking out knockout holes
•
To punch out a knockout hole, hit it with a hammer.
•
Open an appropriate hole as needed.
•
After knocking out the holes, trim off the burr, then we recommend
you to paint the edges and areas around the edges using the repair
paint to prevent rusting.
•
Power line: Open a knockout hole as shown at right and connect it
using a conduit.
Choose an appropriate knockout hole for conduit size suitable for
the power and ground line to be used.
•
Transmission line: Connect it using a conduit in the knockout hole
on the left.
Knockout hole (Transmission line)
f
7/8 in. (22.2 mm)
Knockout hole (Power line)
Burr
f
7/8 in. (22.2 mm)
f
1-1/8 in. (27.8 mm)
f
1-3/8 in. (34.5 mm)
NOTE
After wiring work is completed, check to make sure there are no loose
connections among the electrical parts in the control box.
10 . Air tight test and vacuum drying
• After finished piping work, carry out air tight test and vacuum drying.
NOTE
•
Always use nitrogen gas for the air tightness test.
•
Absolutely do not open the stop valve until the main power circuit
insulation measurement has been completed. (Measuring after the
stop valve is opened will cause the insulation value to drop.)
<Needed tools>
Gauge manifold
Charge hose
valve
•
To prevent entry of any impurities and insure
sufficient pressure resistance, always use the
special tools dedicated for R410A.
•
Use charge hose that have pushing stick for con-
necting to service port of stop valves or refriger-
ant charge port.
Vacuum pump
•
The vacuum pump for vacuum drying should be
able to lower the pressure to 500 microns.
• Take care the pump oil never flow backward into
the refrigerant pipe during the pump stops.
<The system for airtight test and vacuum drying>
• Referring to the figure below, connect a nitrogen tank, refrigerant
tank, and a vacuum pump to the outdoor unit.
The refrigerant tank and the charge hose connection to refrigerant
charge port or the valve A in the figure below are needed in
14. Charging refrigerant on page 26.
1
2
3
4
5
6
B
9
8
11
11
12
10
14
13
15
16
A
C
7
1 Pressure reducing valve
2 Nitrogen
3 Measuring instrument
4 Refrigerant R410A tank (siphon system)
5 Vacuum pump
6 Charge hose
7 High/low pressure gas pipe stop valve
8 Suction gas pipe stop valve
9 Liquid pipe stop valve
10 Refrigerant charge port
11 Outdoor unit
12 To Branch Selector unit (indoor unit)
13 Stop valve
14 Field piping
15
Gas flow
16 Stop valve service port
A Valve A
B Valve B
C Valve C
NOTE
•
The air-tightness test and vacuum drying should be done using the
service ports of suction gas pipe, high/low pressure gas pipe and
liquid pipe stop valve. See the [R410A] Label attached to the front
panel of the outdoor unit for details on the location of the service
port (see the figure below).
REYQ72T
REYQ96-168T
[R410A] Label
[R410A] Label
• See 14.3. Method for adding refrigerant on page 28 for details on
handling the stop valve.
•
The refrigerant charge port is connected to unit pipe. When
shipped, the unit contains the refrigerant, so use caution when at-
taching the charge hose.
<Air tight test>
Pressurize the suction gas pipe, high/low pressure gas pipe and liquid
pipe from the service ports of each stop valve to 550 psi (3.8 MPa) (do
not pressurize more than 550 psi (3.8 MPa)). If the pressure does not
drop within 24 hours, the system passes the test.
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