CAUTION: If visual verification of the valve stem reaching the
retaining ring is impossible, stop backing out the
valve stem when the slightest increase in resis-
tance is felt. Because of the small size and there-
fore the reduced resistance, back out the liquid
valve 5 turns maximum to prevent going past the
retaining ring.
WARNING: If the valve stem is backed out past the retaining
ring, the O’ring can be damaged causing leakage
or system pressure could force the valve stem out
of the valve body possibly causing personal injury.
In the event the retaining ring is missing, do not
attempt to open the valve.
Replace plunger cap finger tight, then tighten an additional 1/12
turn (1/2 hex flat). Cap must be replaced to prevent leaks.
LINE CONNECTION
Connect the refrigerant lines using the following procedure:
1. Remove the cap and Schrader core from both the liquid and
vapor angle valve service ports at the outdoor unit. Connect
low pressure nitrogen to the liquid line service port.
2. Braze the liquid line to the liquid valve at the outdoor unit.
Be sure to wrap the valve body with a wet rag. Allow the
nitrogen to continue flowing.
3. Carefully remove the rubber plugs from the evaporator
liquid and vapor connections.
CAUTION: The evaporator is pressurized.
4. Braze the liquid line to the evaporator liquid connection. The
nitrogen should now be flowing through the evaporator coil.
5. Slide the grommet away from the vapor connection at the
coil. Braze the vapor line to the evaporator vapor connec-
tion. After the connection has cooled, slide the grommet
back into original position.
6. Protect the vapor valve with a wet rag and braze the vapor
line connection. The nitrogen flow should be exiting the
system from the vapor service port connection. After this
connection has cooled, remove the nitrogen source from
the liquid fitting service port.
7. Evacuate the vapor line, evaporator and the liquid line, to
1000 microns or less.
8. Leak test all refrigerant piping connections including the serv-
ice port flare caps to be sure they are leak tight. DO NOT
OVERTIGHTEN (between 40 and 60 inch - lbs. maximum).
NOTE: Do not use the system refrigerant in the outdoor unit
to purge or leak test.
9. Do not remove the flare caps from the service ports except
when necessary for servicing the system.
CAUTION: Do not connect manifold gauges unless trouble is
suspected. Approximately 3/4 ounce of refrigerant
will be lost each time a standard manifold gauge is
connected.
10. Release the refrigerant charge into the system. Open both
the liquid and vapor valves by removing the plunger cap
and with an allen wrench back out counter-clockwise until
valve stem just touches retaining ring. See Figure 7. Re-
lease the refrigerant charge into the system. See "Precau-
tions During Brazing Angle Valves" on page 4 and 5.
11. If the refrigerant tubing, indoor evaporator coil or outdoor
condensing unit has developed a leak during shipment, or
was, for any other reason, opened to the atmosphere for
more than four (4) minutes, it is necessary to evacuate the
system down to at least 1000 microns to eliminate contami-
nation and moisture in the system.
If a leak is suspected, leak test to locate the leak. To verify
the leak, close the valve to the vacuum pump suction to
isolate the pump and hold the system under vacuum. If the
micron gauge indicates a steady and continuous rise after
a few minutes, it’s an indication of a leak. If the guage shows
a rise, then levels off after a few minutes and remains fairly
constant, its an indication that the system is leak free, but
still contains moisture and may require further evacuation
if the reading is above 1000 microns.
WARNING: Never attempt to repair any brazed connections
while the system is under pressure. Personal injury
could result.
See "System Start Up" section for checking and recording
system charge.
FIGURE 6 - HEAT PROTECTION
ANGLE
VALVE
PLUNGER
CAP
FIGURE 7 - REMOVING PLUNGER CAP
550.37-N1Y
Central Environmental Systems
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