Fig.6-1
9
Installation Manual
Precautions should be taken to prevent heat damage to service valve
by wrapping a wet rag around it as shown in Fig. 6.
Also, protect all painted surfaces, insulation, during brazing. After
brazlng cool joint with wet rag.
6.3 PRECAUTIONS DURING BRAZING SERVICE VALVE
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a hex wrench into the stem and backing out counter-clockwise until
valve stem just touches the chamfered retaining wall.
1. Remove the cap and Schrader core from both the liquid
and vapor service valve service ports at the outdoor
unit. Connect Iow pressure nitrogen to the liquid line
service port.
Connect the refrigerant lines using the following procedure:
CAUTION
Dry nitrogen should always be supplied through the tubing while it
is being brazed, because the temperature required is high enough
to cause oxidation of the copper unless an inert atmosphere is
provide. The flow of dry nitrogen should continue until the joint has
cooled. Always use a pressure regulator and safety valve to insure
that only low pressure dry nitrogen is introduced into the
tubing.Only a small flow is necessary to displace air and prevent
oxidation.
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. Refer to the Tabular Data Sheet for proper liquid line sizing.
3. Carefully remove the rubber plugs from the evaporator liquid and vapor
connections at the indoor coil.
4. Braze the liquid line to the evaporator liquid connection. Nitrogen
should be flowing through the evaporator coil.
5. Slide the plastie cap away from the vapor connection at the indoor coil.
Braze the vapor line to the evaporator vapor connection. Refer to the
Table 1 for proper vapor line sizing.
6. Protect the vapor valve with a wet rag and braze the vapor line connection
to the outdoor unit. 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. Replace the Schrader core in the liquid and vapor valves.
8. Leak test all refrigerant piping connections including the service port
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or less.
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vertical differential.
2. Do not increase or decrease tubing sizes.
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nitrogen and leak tested with a bubble type leak detector. Than
release the nitrogen charge. Do not use the system refrigerant in
the outdoor unit to purge or leak test.
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the service ports except when necessary for servicing the system.
11. Release the refrigerant charge into the system. Open both the
liquid
and vapor valves by removing the plunger cap and with an hex
wrench back out counter-clockwise until valve stem just touches the
chamfered retaining wall.
12. Replace plunger cap finger tight, then tighten an additional 1/12
turn (1/2 hex flat). Cap must be replaced to prevent leaks.
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.
WARNING
Never attempt to repair any brazed connections while the system is
under pressure. Personal injury could result.
See "System Charge" section for checking and recording system
charge.
NOTE
NOTE