Leak Testing (Nitrogen Or Nitrogen-Traced); System Evacuation; Safe Refrigerant Handling - Goodman MSC24 Serie Manual De Instalación Y Funcionamiento

Leak Testing (Nitrogen or Nitrogen-Traced)

Pressure test the system, using dry nitrogen and soapy water
to locate any leaks in the system. If you wish to use a leak
detector, charge the system to 10 psi using the appropriate
refrigerant, then use nitrogen to finish charging the system to
working pressure. Apply the detector to suspect areas. If
leaks are found, repair them. After repair, repeat the pressure
test. If no leaks exist, proceed to System Evacuation.

System Evacuation

Condensing unit liquid and suction valves are closed to contain
the charge within the unit. The unit is shipped with the valve
stems closed and caps installed. Do not open valves until
the system is evacuated.
1. Connect the vacuum pump with 250 micron capability to
the service valves.
2. Evacuate the system to 250 microns or less using suc-
tion AND liquid service valves. Using both valves is nec-
essary as some compressor create a mechanical seal
separating the sides of the system.
3. Close the pump valve and hold vacuum for 10 minutes.
Typically, pressure will rise during this period.
NOTES:
• If the pressure rises to 1000 microns or less and re-
mains steady, the system is considered leak-free; pro-
ceed to start-up.
• If pressure rises above 1000 microns but hold steady
below 2000 microns, moisture and/or non-condensables
may be present or the system may have a small leak.
Return to step 2. If the same result is encountered,
check for leaks as previously indicated and repair as
necessary, then repeat evacuation.
• If pressure rises above 2000 microns, a leak is present.
Check for leaks as previous indicated and repair as nec-
essary then repeat evacuation.
Connective Evacuation
Model
Pipe Length Method
Less than Use
24.5' (7.5m) Vacuum Pump
15 SEER
More than Use
24.5' (7.5m) Vacuum Pump
Less than Use
16' (5m) Vacuum Pump
19 SEER
More than Use
16' (5m) Vacuum Pump
Pipe Length and Refrigerant Amount
Additional Amount of Refrigerant
to be Charged
---
R410A (Pipe Length-5)
x 0.3 oz./ft. (20 g/m)
---
R410A (Pipe Length-5)
x 0.3 oz./ft. (20 g/m)
• When relocating the unit to another place, perform the
evacuation using a vacuum pump.
• Refrigerant added to the unit must be in liquid form. (Does
not apply to units using R-22.)

Safe Refrigerant Handling

While these items will not cover every conceivable situation,
they should serve as a useful guide.
WARNING
Refrigerants are heavier than air. They can "push out"
the oxygen in your lungs or in any enclosed space.To
avoid possible difficulty in breathing or death:
• Never purge refrigerant into an enclosed room or
space. By law, all refrigerants must be reclaimed.
• If an indoor leak is suspected, throughly ventilate the
area before beginning work.
• Liquid refrigerant can be very cold. To avoid possible
frostbite or blindness, avoid contact and wear gloves
and goggles. If liquid refrigerant does contact your
skin or eyes, seek medical help immediately.
• Always follow EPA regulations. Never burn refrig-
erant, as poisonous gas will be produced.
WARNING
To avoid possible explosion:
• Never apply flame or steam to a refrigerant cylinder.
If you must heat a cylinder for faster charging,
partially immerse it in warm water.
• Never fill a cylinder more than 80% full of liquid re-
frigerant.
• Never add anything other than R-22 to an R-22 cy-
linder or R-410A to an R-410A cylinder. The service
equipment used must be listed or certified for the
type of refrigerant used.
• Store cylinders in a cool, dry place. Never use a cy-
linder as a platform or a roller.
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