Daikin RXYQ96PYDN, Service Manual

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Test Operation SiUS34-801A_b
76 VRVIII R-410A Heat Pump 60Hz
10.2.3 Air Tight Test and Vacuum Drying
After finishing piping work, carry out airtight test and vacuum drying.
Note:
Always use nitrogen gas for the airtightness test.
Absolutely do not open the shutoff valve until the main power circuit insulation measurement
has been completed. Measuring after the shutoff valve is opened will cause the insulation value
to drop.
<Needed tools>
<The system for air tight test and vacuum drying>
Referring to figure 25, connect a nitrogen tank, refrigerant tank, and a vacuum pump to the
outside unit.
The refrigerant tank and the charge hose connection to refrigerant charge port or valve A in
figure 25 are needed in
10.2.5 Additional Refrigerant Charge and Check Operation .
Gauge manifold
Charge hose
valve To prevent entry of any impurities and insure sufficient pressure
resistance, always use the special tools dedicated for R-410A.
Use charge hose that has a pushing stick for connecting to service port of
shutoff valves or refrigerant charge port.
Vacuum pump The vacuum pump for vacuum drying should be able to lower the pressure
to –14.6 psi.
Take care the pump oil never flows backward into the refrigerant pipe
when the pump stops.
Gauge manifold
Nitrogen
Measuring
device
R-410A tank (with siphon)
Vacuum pump
Charge hose
High side equalizer pipe shutoff valve
Gas pipe shutoff valve
Low side equalizer pipe shutoff valve
Liquid pipe shutoff valve
Valve B
Outside unit Outside unit
Indoor unit
Shutoff valve
Refrigerant charge port
Valve A
: Field piping
: Gas flow
Valve C
( Service port)
Gauge manifold
Nitrogen
Measuring
device
R-410A tank (with siphon)
Vacuum pump
Charge hose
Refrigerant charge port
Gas pipe shutoff valve
Liquid pipe shutoff valve
Outside unit
Indoor unit
Valve A
Valve B
: Field piping
: Gas flow
Valve C
( )
: Shutoff valve
: Service port
< RXYQ144PTJU Only >
fig. 25