1. Superheat_Subcooling:

_ Close both two ports of the gauge

_ Hook up both sides with two hoses (Blue_Red) to ports and two thermocouples (>= 6 " to Comp for SH, close to port as possible bween TXV for SC) to lines

_ Turn on the unit; keep closed both sides of gauge, to have SH and SC

2. Charging for R410A & R22: ;

Unit with TXV, use Subcooling:

_ Locate unit required SC at the nameplate or literature (Typical 8-12 F)

_ Required SC - LSAT = Required liquid line T

* Liquid line T measured > Required liquid line T => add freon (short of freon=> not release heat=> too hot liquid line

* Liquid line T measured < Required liquid line T => remove freon

Unit without TXV, use Superheat chart or :

_ Measure IDWB, ODDB

_ Locate required SH from chart

_ Required SH + VSAT = Required suction line T

* Suction line T measured > Required suction line T => add freon (short freon, absorb too much heat=> hotter suction line

* Suction line T measured < Required suction line T => remove freon

*R314a should be charged in liquid (up side down the tank).(<=0.4 oz for commercial/home refrigerator)

3. Check leak with N₂  when the system emptied

_ Yellow hose (middle) -> N₂ gauge tank

_ Blue line -> low side only

_ Close tightly both ports of manifold (Blue and Red)

_ Open the blue port

_ Purge, Release N₂ to reach around 150_200 Psig, close and hold N₂ at the  pressure for 10 mns

_ Leak detector, Bubble soap applied to check suspected points

4. Vacuum (3 times)

_ Remove cores if possible

_ Hook up to hoses to both sides of the unit; and Yellow hose-> vacuum machine

_ Open both ports at the manifold; and slowly release refrigerant from yellow hose until pressure down to 0.

_  Tightly close yellow hose to manifold

_Turn on the vacuum machine, turn on vacuum switch on machine, open two ports at the gauge

* Pull 1^st vacuum 1000 microns, (take around 15mns).

_Close three hoses, turn off switch, turn off machine

_Hook up Yellow hose to N₂ tank, break N₂ high side    

_ Pull 2^nd to 750 microns for both side, break N₂ low side

* Pull final VAC 500 microns

_ Close all hoses, close switch, turn off machine.

_ Charge refrigerant into high side:  the tank of refrigerant turned a few times and put up side down to charge around 80% amount of liquid or until it not moving into the high side. Note: purge the yellow hose (charge hose) to prevent air getting into the system.

_ Turn on system and check SH/SC and charge (up side up the tank) refrigerator to low side now if needed

5. Pump down:

_ Hook up the gauge to both sides

_ Remove low side and high side service valve caps

_ Close high side at service valve, open low side

_ Turn on the unit

_ Follow the gauge until pressure in the low side hit zero quickly close the service valve (suction valve), kill the power .

_ After do the job on low side, close yellow hose, open both sides, the liquid will balance pressure both sides.

6. Recovery:

_ Vacuum the tank

_ Turn off system and wait until equality

_ Both sides (Low and High) open at the same time, turn on machine

_ Recover until blue gauge of machine reach 0 Psi, Close all valves and turn off machine.

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