Installation manual

835966-UIM-D-0614
4 Johnson Controls Unitary Products
PRECAUTIONS DURING BRAZING OF LINES
All outdoor unit and evaporator coil connections are copper-to-copper
and should be brazed with a phosphorous-copper alloy material such
as Silfos-5 or equivalent. DO NOT use soft solder. The outdoor units
have reusable service valves on both the liquid and vapor connections.
The total system refrigerant charge is retained within the outdoor unit
during shipping and installation. The reusable service valves are pro-
vided to evacuate and charge per this instruction.
Serious service problems can be avoided by taking adequate precau-
tions to assure an internally clean and dry system.
PRECAUTIONS DURING BRAZING SERVICE VALVE
Wrap a wet rag around the service valve as shown in Figure 4 to pre-
vent heat damage. Also, protect all painted surfaces, insulation, and
plastic base during brazing. After brazing, cool joint with wet rag.
Valve can be opened by removing the plunger cap and fully inserting a
hex wrench into the stem and backing out counter-clockwise until valve
stem just touches the chamfered retaining wall.
Connect the refrigerant lines using the following procedure:
1. Remove the cap and Schrader core from both the liquid and vapor
service valve ports at the outdoor unit. Connect low pressure nitro-
gen 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. Refer to the Tabular Data Sheet for proper liquid line sizing.
3. Go to “SECTION IV” or “SECTION V” for orifice or TXV installation
depending on application.
4. Braze the liquid line to the evaporator liquid connection. Nitrogen
should be flowing through the evaporator coil.
5. Remove the split rubber grommet from the vapor connection at the
indoor coil. Braze the vapor line to the evaporator vapor connection.
After the connection has cooled, place the rubber grommet back into
the mounting position. Refer to the Tabular Data Sheet for proper
vapor line sizing.
6. Protect the vapor valve with a wet rag and braze the vapor line con-
nection 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 and repair leaks in all refrigerant piping connections includ-
ing the service port flare caps. DO NOT OVERTIGHTEN caps.
Torque caps between 40 and 60 inch - lbs. maximum.
9. Evacuate the vapor line, the evaporator, and the liquid line to 500
microns or less in accordance with the EVACUTATION procedures.
10.Release the refrigerant charge into the system in accordace with the
SYSTEM CHARGE procedures. Open the liquid line base valve first
and let pressures equalize. Then, open the suction line base valve.
When opening either valve, use an appropriate hex head wrench
and back seat the base valve by turning it counter clockwise until it
stops against the chamford retaining wall, and then turn it back 1/8
turn. If the service valve is a ball valve, use an adjustable end
wrench to turn valve stem one-quarter turn counterclockwise to
open. Do not overturn (or the valve stem may break or become dam-
aged).
11.To prevent leaks, replace base valve caps finger tight, and then
tighten the cap an additional 1/12 turn (1/2 hex flat).
12.Replace cap on service ports. Do not remove the flare caps from the
service ports except when necessary for servicing the system.
13.See “System Charge” section for checking and recording system
charge.
FIGURE 3: Underground Installation
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 provided.
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.
This is not a backseating valve. The service access port has a valve
core. Opening or closing valve does not close service access port.
If the valve stem is backed out past the chamfered retaining wall, 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.
FIGURE 4: Heat Protection
TO INDOOR COIL TO OUTDO OR UNIT
LIQUID LINE
CAP
PVC
CONDUIT
INSULATED
VAPOR LINE
Do not install any coil in a furnace which is to be operated during the heat-
ing season without attaching the refrigerant lines to the coil. The coil is
under 30 to 35 psig inert gas pressure which must be released before
brazing lines to prevent excessive pressure build-up and possible coil
damage.
Never attempt to repair any brazed connections while the system is under
pressure. Personal injury could result.
Refrigeration piping and indoor coil can be pressurized to 250 psig with
dry nitrogen and leak tested with a bubble type leak detector. Then
release the nitrogen charge.
Do not use the system refrigerant from the outdoor unit to purge or leak
test the system.
Do not connect manifold gauges unless trouble is suspected. Approxi-
mately 3/4 ounce of refrigerant will be lost each time a standard manifold
gauge is connected.
NOTICE