English
7
Outdoor Unit Installation
4-1 Cautions on pipe handling
1) Protect the open end of the pipe against dust and moisture.
2) All pipe bends should be as gentle as possible. Use a pipe bender
for bending.
4-2 Selection of copper and heat insulation materials
When using commercial copper pipes and fittings, observe the following:
1) Insulation material: Polyethylene foam
Heat transfer rate: 0.041 to 0.052W/mK (0.035 to 0.045kcal/mh°C)
Refrigerant gas pipe’s surface temperature reaches 110°C max.
Choose heat insulation materials that will withstand this temperature.
2) Be sure to insulate both the gas and liquid piping and to provide insulation
dimensions as below.
3) Use separate thermal insulation for gas and liquid refrigerant pipes.
5.
Evacuating the air with a vacuum pump and checking gas leakage
WARNING
• Do not mix any substance other than the specified refrigerant (R32) into the refrigeration cycle.
• When refrigerant gas leaks occur, ventilate the room as soon and as much as possible.
• R32, as well as other refrigerants, should always be recovered and never be released directly into the environment.
• Use a vacuum pump for R32 or R410A exclusively. Using the same vacuum pump for different refrigerants may damage the
vacuum pump or the unit.
• Use tools for R32 or R410A (such as the gauge manifold, charging hose, or vacuum pump adapter).
• When piping work is completed, it is necessary to evacuate the air and check for gas
leakage.
• If using additional refrigerant, perform air evacuating from the refrigerant pipes
and indoor unit using a vacuum pump, then charge additional refrigerant.
• Use a hexagonal wrench (4mm) to operate the stop valve rod.
• All refrigerant pipe joints should be tightened with a torque wrench at the specified
tightening torque.
Gas side
Liquid side
Gas pipe
thermal insulation
Liquid pipe
thermal insulation
O.D. 9.5mm
O.D. 6.4mm
I.D. 12-15mm
I.D. 8-10mm
Minimum bend radius
Thickness 10mm Min.
30mm or more
Thickness 0.8mm (C1220T-O)
1) Connect projection side of charging hose (which comes from gauge manifold) to gas stop valve’s service port.
2) Fully open gauge manifold’s low-pressure valve (Lo) and completely close its high-pressure valve (Hi).
(High-pressure valve subsequently requires no operation.)
3) Do vacuum pumping and make sure that the compound pressure gauge reads –0.1MPa (–76cmHg).*1
4) Close gauge manifold’s low-pressure valve (Lo) and stop vacuum pump.
(Keep this state for a few minutes to make sure that the compound pressure gauge pointer does not swing back.)*2
5) Remove caps from liquid stop valve and gas stop valve.
Wall
If no flare cap is
available, cover the
flare mouth with
tape to keep dirt
or water out.
Be sure to
place a cap.
Rain
Gas pipe
Inter-unit wire
Liquid pipe
Drain hose
Finishing tape
Gas pipe
insulation
Liquid pipe
insulation
Compound
pressure gauge
Pressure
metre
High-
pressure
valve
Low-pressure
valve
Vacuum pump
Service port
Liquid
stop
valve
Valve caps
Gas stop valve
Charging
hoses
Gauge
manifold
Summary of Contents for RXJ20M2V1B
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