AUX ACHP-H04/4R3HA, Техническое и сервисное руководство

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R32 Split Type - Air Source Heat Pump 20220105
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to a joint
Leak detection
4. Refrigerant leak detection: for leaks that are difficult to detect, refrigerant leak detection may be used as
follows:
a) Pressurize the piping with nitrogen at 0.3MPa.
b) Add refrigerant into the piping until the pressure reaches 0.5MPa.
c) Use a halogen refrigerant detector to find the leak.
d) If the leak source cannot be found, continuing charging with refrigerant to a pressure of 4.3 MPa and then
search again.
2.10 Vacuum Drying
2.10. 1 Purpose
Vacuum drying should be performed in order to remove moisture and noncondensable gases from the system.
Removing moisture prevents ice formation and oxidization of copper piping or other internal components. The
presence of ice particles in the system would cause abnormal operation, whilst particles of oxidized copper can
cause compressor damage. The presence of noncondensable gases in the system would lead to pressure
fluctuations and poor heat exchange performance.
2.10.2 Procedure
A vacuum pump is used to lower the pressure in the piping to the extent that any moisture present
evaporates. At 5mmHg (755mmHg below typical atmospheric pressure) the boiling point of water is 0C.
Therefore a vacuum pump capable of maintaining a pressure of755mmHg or lower should be used. Using a
vacuum pump with a discharge in excess of 4L/s and a precision level of 0.02mmHg is recommended.
Caution

Before performing vacuum drying, make sure that the outdoor unit stop valves are firmly closed.

Once the vacuum drying is complete and the vacuum pump is stopped, the low pressure in the piping
could suck vacuum pump lubricant into the air conditioning system. The same could happen if the vacuum
pump stops unexpectedly during the vacuum drying procedure. Mixing of pump lubricant with compressor
oil could cause compressor malfunction and a oneway valve should therefore be used to prevent vacuum
pump lubricant seeping into the piping system.
Procedure
The vacuum drying procedure is as follows:
Step 1
Connect the blue (low pressure side) hose of a pressure gauge to the outdoor unit gas pipe stop valve, the red
(high pressure side) hose to the outdoor unit liquid pipe stop valve and the yellow hose to the vacuum pump.
Step 2