Mitsubishi Electric MUZ-FA25VA-E1 Service Manual page 5

Mitsubishi ilmalämpöpumput huoltaa ja korjaa: Jäähdytinpalvelu RefGroup Oy
2.Refrigerant piping
1 Specifications
Use the refrigerant pipes that meet the following specifications.
Pipe
For liquid
For gas
• Use a copper pipe or a copper-alloy seamless pipe with a thickness of 0.8 mm. Never use any pipe with a thickness less
than 0.8mm, as the pressure resistance is insufficient.
2 Flaring work and flare nut
Flaring work for R410A pipe differs from that for R22 pipe.
For details of flaring work, refer to Installation manual "FLARING WORK".
Pipe diameter
mm
6.35
9.52
12.7
3.Refrigerant oil
Apply the special refrigeration oil (accessories: packed with indoor unit) to the flare and the union seat surfaces.
4.Air purge
• Do not discharge the refrigerant into the atmosphere.
Take care not to discharge refrigerant into the atmosphere during installation, reinstallation, or repairs to the refrigerant
circuit.
• Use the vacuum pump for air purging for the purpose of environmental protection.
5.Additional charge
For additional charging, charge the refrigerant from liquid phase of the gas cylinder.
If the refrigerant is charged from the gas phase, composition change may occur in the refrigerant inside the cylinder and the
outdoor unit. In this case, ability of the refrigeration cycle decreases or normal operation can be impossible. However,
charging the liquid refrigerant all at once may cause the compressor to be locked. Thus, charge the refrigerant slowly.
Refrigerant gas
cylinder
operating valve
Outside diameter
Wall
mm thickness
0.8 mm
6.35
0.8 mm
9.52
0.8 mm
12.7
R410A
Union
Indoor unit
Charge hose (for R410A)
Refrigerant gas cylinder
for R410A with siphon
Refrigerant (liquid)
Electronic scale for refrigerant charging
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Insulation material
Heat resisting foam plastic
Specific gravity 0.045 Thickness 8 mm
Dimension of flare nut
R22
17
22
26
Stop valve
Liquid pipe
Gas pipe
Service port
Gauge manifold
valve (for R410A)
4
17
22
24
Outdoor unit