16
A5HDC-2009
Application Information
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 weight composition 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 should 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is being withdrawn from the cylinder or can.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 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 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
• Tool (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
