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AWM-G-2009 Application Information
3) CHARACTERISTIC
R410A liquid and vapor components have different compositions when the fl uid evaporates or
condenses.Hence, when leak occurs and only vapor leaks out, the composition of the refrigerant
mixture left in thesystem will change and subsequently affect the system performance. DO NOT add
new refrigerant toleaked system. It is recommended that the system should be evacuated thoroughly
before recharging withR410A.
When refrigerant R410A is used, the composition will differ depending on whether it is in gaseous or
liquidphase. Hence when charging R410A, ensure that only liquid is being withdrawn from the cylinder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
R22compressor. Extra precaution must be taken not to expose the R410A system too long to moist air.
4) CHECK LIST BEFORE INSTALLATION/SERVICING
Tubing
Refrigerant R410A is more easily affected by dust of moisture compared with R22, make sure to
temporarilycover 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 specifi cally for R410A only (must not be used for R22 or other refrigerant)
i) Manifold gauge and charging hose
ii) Gas leak detector
iii) Refrigerant cylinder/charging cylinderiv)Vacuum pump c/w adapter
v) Flare tools
vi)Refrigerant recovery machine
5) HANDLING AND INSTALLATION GUIDELINES
Like R22 system, 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 leakcheck and vacuuming are equally important requirements. However, due to its hydroscopic
POE oil, additionalprecautions 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 tomoist
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 specifi ed byits
manufacturer (typically less than 10 minutes). Removed the seal plugs only when the compressor isabout
to be brazed.
c) The system should be thoroughly vacuumed to 1.0 Pa ( 700mmHg) or lower. This vacuuming level ismore
stringent than R22 system so as to ensure no incompressible gas and moisture in the system.
d) When charging R410A, ensure that only liquid is being withdrawn from the cylinder or can. This is toensure
that only the original composition of R410A is being delivered into the system. The liquid compositioncan
be different from the vapor composition.
Dip-pipe
Liquid
withdrawal
Invert cylinder
without dip-pipe
f) Normally, the R410A cylinder or can is being equipped with a dip pipe for liquid withdrawal. However,
if thedip pipe is not available, invert the cylinder or can so as to withdraw liquid from the valve at the
bottom.
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