⑤
⑥
Unscrew the nuts of valve A and B and turn on Valve A and Valve B, then
tighten their nuts.
Take down Charging hose at A joint, then tighten the nut.
Outdoor unit
Refrigerant pipe
To indoor unit
Check valve
Charging hose 1
Charging hose 2
Multimeter
Pressure gauge
High pressure handle
Low pressure handle
Vacuum
pump
Manifold
Fig 21
5 2 2 4 Air leakage test: Water soap suds to connectors and joints of valves
to check whether there is any leakage at the joints.
5
.
2
.
2
.
5
Heat preservation: After leakage test and pressure test, wrap the pipe
with the insulating material .Request of the insulation layer.
■
Insulation layer of pipeline should be 8 mm at least and wrapped up tightly.
■
Process the surface of the insulation lay for waterproof and moisture
-
proof
(usually wrap the pipe with the bend).
■
It is not allowed for the surface with dew when the unit is in cooling mode.
5
.
2
.
2
.
6
New tools for R410A
. . .
New tools for R410A
Changes
Gauge manifold
If the working pressure is quite high, it is impossible to measure the pressure
with the conventional gauge. In order to prevent any other refrigerant from being
charged, the diameter of the port should be changed.
Charge hose
In order to improve the pressure resisting performance, the hose material and the
size of the hose should be changed (1/2 UNF thread, 20 threads per inch). When
purchasing the charge hose, please confirm the size.
Multi-meter
When the working pressure is quite high and the gasification speed is fast, it
s
difficult to read the indicated value for using the charging cylinder.
’
Torque wrench (Nominal
Diameter: 1/4, 3/8 )
The size of the opposing flare nut is increased. Besides, the common wrench is
applicable for the case: The nominal diameter of the port is 1/4 or 3/8.
Flare tool( clutch type)
Increasing the size of hole in the clamp bar can increase the force of the drift
punch of the flare tool.
Cut pipe
Used when making the flare with the conventional flare tool.
Vacuum pump adapter
Connected to the conventional vacuum pump, the adapter can prevent the oil of
the vacuum pump flowing back to the charge hose. The charge hose has two
ports: one for the conventional refrigerant (7/16 UNF thread, 20 threads
per inch) and the other for R410A. If the oil of the vacuum pump is mixed with
some R410A, the sludge will be produced, which will do damage to the
equipment.
Gas leakage detector
Exclusive for the refrigerant HFC
20
Table 5
