MXS Installation Manual

9 ■English
Outdoor Unit Installation
4. Pressure test and evacuating system
WARNING
• Donotmixanysubstanceotherthanthespeciedrefrigerant(R410A)intotherefrigerationcycle.
• If refrigerant gas leaks should occur, ventilate the room as soon and as much as possible.
• R410A, as well as other refrigerants, should always be recovered and never be released directly into the environment.
• Use a vacuum pump for R410A exclusively. Using the same vacuum pump for different refrigerants may damage the vacuum
pump or the unit.
• When piping work is complete, it is necessary to perform a pressure test
and evacuate system with a vacuum pump.
• If using additional refrigerant, perform air purging of the refrigerant pipes
and indoor unit using a vacuum pump, then charge additional refrigerant.
• Useahexagonalwrench(3/16inch(4mm))tooperatethestopvalverod.
• All refrigerant pipe joints should be tightened with a torque wrench to the
speciedtighteningtorque.
Compound
pressure gauge
Pressure
meter
High-pressure
valve
Low-pressure
valve
Vacuum pump
Service port
Liquid
stop
valve
Valve caps
Gas stop valve
Charging
hoses
Gauge
manifold
1)Pressurizetheliquidpipeandgaspipefromtheserviceportsofeachstopvalveto550psi(3.8MPa)(donotpressurize
morethan550psi(3.8MPa))for1hourminimum,24hoursrecommended.Ifthereisapressuredrop,checkforleaks,
make repairs and perform the pressure test again.
2)Connectprojectionsideofcharginghose(whichcomesfromgaugemanifold)togasstopvalve’sserviceport.
3)Fullyopengaugemanifold’slow-pressurevalve(Lo)andcompletelycloseitshigh-pressurevalve(Hi).
(High-pressurevalvesubsequentlyrequiresnooperation.)
4)Evacuate system using vacuum pump to below 500 microns for 1 hour minimum.
5)Closegaugemanifold’slow-pressurevalve(Lo)andstopvacuumpump.
(Leave as is for 4-5 minutes and make sure the coupling meter needle does not go back.
If it does go back, this may indicate the presence of moisture or leaking from connecting parts. After inspecting all the
connectionandlooseningthenretighteningthenuts,repeatsteps3-5.)
6)Remove covers from liquid stop value and gas stop valve.
7)Turn the liquid stop valve’s rod 90° counter-clockwise with a hexagonal wrench to open the valve.
Close it after 5 seconds, and check for gas leakage.
Usingsoapywater,checkforgasleakagefromindoorunit’sareandoutdoorunit’sareandvalverods.
After the check is complete, wipe all soapy water off.
8)Disconnect charging hose from gas stop valve’s service port, then fully open liquid and gas stop valves.
(Donotattempttoturnvalverodbeyonditsstop.)
9)Tightenvalvecapsandserviceportcapsfortheliquidandgasstopvalveswithatorquewrenchtothespeciedtorques.
Refer to “3. Refrigerant Piping” on page 8 for details.
01_EN_3P379970-4.indd 9 11/4/2014 2:50:08 PM