SPECIAL PRECAUTIONS WHEN DEALING WITH REFRIGERANT R410A UNIT
1) WHAT IS NEW REFRIGERANT R410A?
R410A is a new HFC refrigerant which does not damage the ozone layer. The working pressure of this new
refrigerant is 1.6 times higher than conventional refrigerant (R22), thus proper installation / servicing is
essential.
2) COMPONENTS
Mixture of composition by weight : R32(50%) and R125(50%)
3) CHARACTERISTIC
•
R410A liquid and vapor components have different compositions when the fluid evaporates or
condenses. Hence, when leak occurs and only vapor leaks out, the composition of the refrigerant
mixture left in the system will change and subsequently affect the system performance.
DO NOT
add
new refrigerant to leaked system. It is recommended that the system be evacuated thoroughly before
recharging with R410A.
•
When refrigerant R410A is used, the composition will differ depending on whether it is in gaseous or
liquid phase.
Hence when charging R410A, ensure that only liquid is being withdrawn from the cylinder or can. This
is to make certain that only original composition of R410A is being charged into the system.
•
POE oil is used as lubricant for R410A compressor, which is different from the mineral oil used for R22
compressor.
Extra precaution must be taken to avoid exposing the R410A system to moist air.
4) CHECK LIST BEFORE INSTALLATION / SERVICING
•
Tubing
Refrigerant R410A is more easily affected by dust or moisture compared with R22, make sure to
temporarily cover the ends of the tubing prior to installation
•
Compressor oil
No additional charge of compressor oil is permitted.
•
Refrigerant
No other refrigerant other that R410A
•
Tools (size of service port is different from R22 system)
Tools specifically for R410A only (must not be used for R22 or other refrigerant)
i)
Gauge manifold and charging hose
ii)
Gas leak detector
iii)
Refrigerant cylinder/charging cylinder
iv)
Vacuum pump c/w adapter
v)
Flare tools
vi)
Refrigerant recovery machine
5)
HANDLING AND INSTALLATION GUIDELINES
Like R22 systems, the handling and installation of R410A system are closely similar. All precautionary
measures; such as ensuring no moisture, no dirt or chips in the system, clean brazing using nitrogen, and
thorough leak check and vacuuming are equally important requirements. However, due to its hydroscopic
POE oil, additional precautions must be taken to ensure optimum and trouble-free system operation.
a) During installation or servicing, avoid prolong exposure of the internal part of the refrigerant system to
moist air. Residual POE oil in the piping and components can absorb moisture from the air.
b) Ensure that the compressor is not expose to open air for more than the recommended time specified by
its manufacturer (typically less than 10 minutes). Removed the seal-plugs only when the compressor is
about to be brazed.
c) The system should be thoroughly vacuumed to 1.0 Pa ( 700mmHg) or lower. This vacuuming level is
more stringent than R22 system so as to ensure no incompressible gas and moisture in the system.
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Summary of Contents for A5ACV 100 CR
Page 43: ...INSTALLATION A5ACV 30 55 75CR 41 ...
Page 44: ...A5ACV 30CR A5ACV 55CR 75CR 42 ...
Page 78: ...10 WIRING DIAGRAMS PA R T NO 50 13 9 026086 MODEL A5ACV 30CR 76 ...
Page 79: ...77 MODEL A5ACV 55CR ...
Page 80: ...MODEL A5ACV 75CR PA R T NO 50 13 4 083602 78 ...
Page 81: ...MODEL A5ACV 100 135CR 79 ...
