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INSTALLER'S GUIDE
©
GAS LINE SERVICE
VALVE
CAP
_
_
1/4 TURN
ONLY
COUNTERCLOCKWISE
UNIT
SIDE
OF
VALVE
#
PRESSURE
TAP
PORT
j
/
GAS
LINE
CONNECTION
cAP_
CORE
The Gas Line 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 recom-
mended
that the pressure
tap port valve
core he removed
and
a wet
rag wrapped
around
the valve
body.
CAUTION:
Use
care to make
sure
that
no
moisture
enters
pressure
tap port, while
wet
rag is being
used.
6. Remove
braze
shield
from
clear
plastic
bag.
Soak pad in
water
and place over suction
and liquid
lines
to protect
unit
finish.
See Figure
5. Discard
pad when
finished
with brazing.
7. Use a Dry Nitrogen
Purge
and Brazing
Alloy without
flux
when brazing the field line to the copper factory connection.
Flow
dry nitrogen
into either
valve pressure
tap port, thru the tubing
and out the other
port while brazing.
8. Braze using
accepted
good brazing
techniques.
LEAK
CHECK
CAUTION :
In scrollcompressorapplications,
dome
temperatures
may be hot. Do not touch
top of com-
pressor,
may cause
minor
to severe
burning.
IMPORTANT:
Replace
pressure
tap port
valve
core
be-
fore attaching
hoses
for evacuation.
After
the brazing
operation
of refrigerant
lines
to both
the
outdoor
and indoor
unit is completed,
the field brazed
connec-
tions must
be checked
fbr leaks.
Pressurize
through
the service
valve ports, the indoor unit and field refl_igerant
lines with dry
nitrogen
to 200 psi.
Use soap bubbles
or other
leak-checking
methods
to see that all field joints are leak-fl'ee!
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 colnpletion
ofleak
check, evacu ate the refrigerant
lines
and indoor coil befbre opening
the gas and liquid line valves.
2. Attach
appropriate
hoses
froJn manififld
gauge
to gas and
liquid line pressure
taps.
NOTE:
Unnecessary
switching
of hoses can
be avoided
and
complete
evacuation
of'all
lines leading
to sealed
system can be
accomplished
with mani[bld
center hose and connecting
branch
hose to a qylinder
of HCFC-22
and vacuum
pump.
3. Attach
center
hose of manifbld
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. Ifgaugepressurerisesabove
500micronsinone
(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. With vacuum
pump and micron gauge blanked
off, open valve
on HCFC-22
cylinder
and charge
rel?igerant
lines and indoor
coil with vapor to tank pressure
of HCFC-22
supply.
NOTE:
DO
NOT
VENT
REFRIGERANT
INTO
THE
ATMOSPHERE.
8. Close valve on HCFC-22
supply
cylinder.
Close valves
on
manifold
gauge set and remove
refrigerant
charging
hoses from
liquid and gas pressure
tap ports.
HEAT SHIELD
Pub. No. 18-AC34D1-5
PAGE 3
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