Vacuuming And Charging - McQuay J-Serie Montageanleitung

SPECIAL PRECAUTIONS WHEN DEALING WITH R410A UNIT
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.
• Never use refrigerant other than R410A in an air
conditioner which designed to operate with R410A.
• POE oil is used as lubricant for R410A compressor, which
is different from the mineral oil used for R22 compressor.
During installation or servicing, extra precaution must
be taken not to expose the R410A system too long to moist
air. Residual POE oil in the piping and components can
absorb moisture from the air.
• To prevent mischarging, the diameter of the service port
on the flare valve is different from that of R22.
Purging The Piping And The Indoor Unit
Except for the outdoor unit which is pre-charged with
refrigerant, the indoor unit and the refrigerant
connection pipes must be air-purged because the air
containing moisture that remains in the refrigerant cycle may
cause malfunction of the compressor.
• Remove the caps from the valve and the service port.
• Connect the center of the charging gauge to the vacuum
pump.
• Connect the charging gauge to the service port of the
3-way valve.
• Start the vacuum pump. Evacuate for approximately
30 minutes. The evacuation time varies with different
vacuum pump capacity. Confirm that the charging gauge
needle has moved towards -760mmHg.
Caution
• If the gauge needle does not move to -760mmHg, be sure
to check for gas leaks (using the refrigerant
detector) at flare type connection of the indoor and outdoor
unit and repair the leak before proceeding to the next step.
• Close the valve of the charging gauge and stop the vacuum
pump.
• On the outdoor unit, open the suction valve (3 way) and
liquid valve (2 way) (in anti-clockwise direction) with 4mm
key for hexagon sacked screw.
Charge Operation
This operation must be done by using a gas cylinder and a
precise weighing machine. The additional charge is topped-up
into the outdoor unit using the suction valve via the service
port.
• Remove the service port cap.
• Connect the low pressure side of the charging gauge to the
suction service port center of the cylinder tank and close
the high pressure side of the gauge. Purge the air from the
service hose.
• Start the air conditioner unit.
• Open the gas cylinder and low pressure charging valve.
• When the required refrigerant quantity is pumped into the
unit, close the low pressure side and the gas cylinder valve.
• Disconnect the service hose from service port. Put back the
service port cap.
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VACUUMING AND CHARGING

Indoor Unit
1-10
Use tools and materials exclusively for refrigerant R410A.
Tools exclusively for R410A are manifold valve, charging
hose, pressure gauge, gas leak detector, flare tools, torque
wrench, vacuum pump and refrigerant cylinder.
As an R410A air conditioner incurs higher pressure than
R22 units, it is essential to choose the copper pipes
correctly. Never use copper pipes thinner than 0.8mm even
though they are available in the market.
If the refrigerant gas leakage occurs during installation /
servicing, be sure to ventilate fully. If the refrigerant gas
comes into contact with fire, a poisonous gas may occur.
When installing or removing an air conditioner, do not
allow air or moisture to remain in the refrigerant cycle.
Allen key
Service port
Liquid side
Indoor Unit
Gas side
Open
Vacuum
Hi
pump
Low
Close
Liquid side
Gas side
Check
valve
Hi
Low
Close
Refrigerant piping
Flare nut
Outdoor unit 3 ways valve
Outdoor Unit
Discharge
valve
Close
Suction
valve
Close
Outdoor Unit
Discharge valve
Open
Suction
valve
Open