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MS-SVN055B-EN
Installation
Evacuation and leak testing
After the installation of refrigerant lines to both the outdoor and indoor units are completed, the
flare
connections must be checked for leaks. Pressurize through the service valve ports, the indoor unit
and field refrigerant lines with dry nitrogen to 350-400 psi. Use soap bubbles or other leak checking
methods to see that all flares are leak-free! If not, release pressure; then repair!
System evacuation
Note:
Inasmuch as the outdoor unit has a refrigerant charge, the gas and liquid line valves must
remain closed.
1. Upon completion of leak check, evacuate the refrigerant lines and indoor coil before opening
the gas and liquid line valves.
2. Attach appropriate hoses from manifold gauge to gas and liquid line pressure taps.
3. Attach center hose of manifold gauge to vacuum pump.
4. Evacuate until the micron gauge reads no higher than 350 microns.
5. Close off valve to vacuum pump and observe the micron gauge. If gauge pressure rises above
500 microns in one (1) minute, then evacuation is incomplete or system has a leak.
6. If vacuum gauge does not rise above 500 microns in one (1) minute, the evacuation should be
complete.
7. Blank off vacuum pump and micron gauge, close valves on manifold gauge set.
Note
:
DO NOT VENT REFRIGERANT INTO THE ATMOSPHERE.
8. The liquid line shut-off valve can now be opened. Remove shut-off-valve cap. Fully insert hex
wrench into the stem and backout counterclockwise open.
WARNING
Danger of Explosion!
Never use an open flame to detect gas leaks. Explosive conditions may occur. Use a leat test
solution or other approved methods for leak testing. Failure to follow recommended safe leak
test procedures could result in death or serious injury or equipment or property-only damage.
WARNING
Danger of Explosion!
Use only dry nitrogen with a pressure regulator for pressurizing unit. Do not use acetylene,
oxigen or compressed air or mixtures containing these for pressure testing. Do not use
mixtures of a hydrogen containing refrigerant and air above atmospheric pressure for pressure
testing, as they may become flammable and could result in an explosion. Refrigerant, when
used as a trace gas, should only be mixed with dry nitrogen for pressurizing units. Failure to
follow these recommendations could result in death or serious injury or equipment or
property-only damage.
