116
3. Torque wrenches (diameters 1/2, 5/8)
In order to strengthen the compressive strength, the
diameters of wrenches change depending on the flare
nut sizes.
Torque wrenches
Differences in torque wrenches
R32
(common R410A)
R22
1/2
(diameter × torque)
26 mm × 55 N•m
(550 k
g
f•cm)
24 mm × 55 N•m
(550 k
g
f•cm)
5/8
(diameter × torque)
29 mm × 65 N•m
(650 k
g
f•cm)
27 mm × 65 N•m
(650 k
g
f•cm)
4. Manifold gauges
R22 gauges cannot be used because of the high
pressures.
Each port of manifold has different shapes in order
to prevent inserting wrong refrigerant.
*However, the port shape for R410A and R32 is the
same; therefore, attention need to be paid not to insert
wrong refrigerant.
Differences in high/low pressure gauges
R32
(common R410A)
R22
High pressure
gauges (red)
-0.1 ~ 5.3 MPa
-76 cmH
g
~ 53 k
g
f / cm
2
-76 cmH
g
~ 35 k
g
f / cm
2
Low pressure
gauges (blue)
-0.1 ~ 3.8 MPa
-76 cmH
g
~ 38 k
g
f / cm
2
-76 cmH
g
~ 17 k
g
f / cm
2
Difference in manifold port sizes
R32
(common R410A)
R22
Port sizes
1/2 UNF20
7/16 UNF20
5. Charging hoses
The pressure resistance of charge hoses is increased.
At the same time, the material is changed to HFC
resistant, and the size of each manifold adopter is
changed, as the port size of manifold gauge itself.
Further, some hoses are with anti-gas pressure
backflow valves placed near the adopters. (hoses with
the valves recommended)
Manifold gauges / Charging hoses
Differences in charging hoses
R32
(common R410A)
R22
Pressure
Resistance
Normal
operation
pressure
5.1 MPa
(52 k
g
f / cm
2
)
3.4 MPa
(35 k
g
f / cm
2
)
Burst
pressure
27.4 MPa
(280 k
g
f / cm
2
)
17.2 MPa
(175 k
g
f / cm
2
)
Material
HNBR rubber
Internal nylon
coating
NBR rubber
6. Vacuum pump and Vacuum pump adopter
When using a vacuum pump, it is necessary to set a
solenoid valve in order to prevent backflow of vacuum
pump oil into the charge hoses, and use a vacuum
pump with oil backflow prevention function, or use the
vacuum pump with vacuum pump adopter.
If vacuum pump oil
(
mineral oil-based
)
mixes with
R410A (R32), it may cause damage to the machine.
Vacuum pump
Vacuum pump adopter