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lIqUId lIne ServICe vAlve
3
WArnInG
!
extreme caution should be exercised when opening the
liquid line Service valve. Turn valve stem counterclockwise
only until the stem contacts the rolled edge. (See Figure
3.) no torque is required. Failure to follow this warning will
result in abrupt release of system charge and may result in
personal injury and/or property damage.
BrASS GAS lIne BAll ServICe vAlve
The Brass Gas Line Ball Service Valve is shipped in the closed
position to hold the factory refrigerant charge. The pressure
tap service port (when depressed) opens only to the field braz-
ing side when the valve is in the closed position. The Gas Line
Ball Service Valve is full open with a 1/4 turn. See Figure 4.
BrAzInG reFrIGerAnT lIneS
1. Before brazing, remove plugs from external copper stub
tubes. Clean internal and external surfaces of stub tubes
prior to brazing.
2. Cut and fit tubing, minimizing the use of sharp 90° bends.
3. Insulate the entire gas line and its fittings.
4. Do NOT allow uninsulated liquid line to come in direct
contact with bare gas line.
5. Precautions should be taken to avoid heat damage
to the pressure tap valve core during brazing. It
is recommended that the pressure tap port valve
core be removed and a wet rag wrapped around the
valve body.
NOTE:
Use care to make sure that no moisture enters pressure tap
port, while wet rag is being used.
NOTE:
Precautions should be taken to avoid heat damage to base-
pan during brazing. It is recommended to keep the flame
directly off of the basepan.
6. Use a Dry Nitrogen Purge and Brazing Alloy without flux
when brazing the field line to the copper factory connec-
tion. Flow dry nitrogen into either valve pressure tap
port, thru the tubing and out the other port while brazing.
7. Braze using accepted good brazing techniques.
leAk CheCk
IMPORTANT:
Replace pressure tap port valve core before attaching hoses for
evacuation.
After the brazing operation of refrigerant lines to both the
outdoor and indoor units is completed, the field brazed con-
nections must be checked for leaks. Pressurize through the
service valve ports, the indoor unit and field refrigerant lines
18-BC76D1-2
Installer's Guide
with dry nitrogen to 350-400 psi. Use soap bubbles or other
leak-checking methods to see that all field joints are leak-free!
If not, release pressure; then repair!
SySTeM evACUATIOn
NOTE:
Since 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.
NOTE:
Unnecessary switching of hoses can be avoided and com-
plete evacuation of all lines leading to sealed system can
be accomplished with manifold center hose and connecting
branch hose to a cylinder of R-410A and vacuum pump.
3. Attach center hose of manifold gauges 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.
4
GAS lIne BAll ServICe vAlve
CAP
UnIT SIde
OF vAlve
PreSSUre TAP POrT
GAS lIne COnneCTIOn
GAS lIne ServICe vAlve
5
1/4 TUrn Only
COUnTerClOCkWISe
FOr FUll OPen
POSITIOn
vAlve STeM
3
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