Tubing Hanger; Underground Installation; Heat Protection - York YZF Installation Manual

835966-UIM-E-0814
7. Pack fiberglass insulation and a sealing material such as permagum
around refrigerant lines where they penetrate a wall to reduce vibra-
tion and to retain some flexibility.
8. See Form 247077 for additional piping information.
LIQUID
LINE
INCORRECT
CORRECT
FIGURE 2: Tubing Hanger
TO INDOOR COI L
LI QUID LINE
PVC
CONDU IT
FIGURE 3: Underground Installation
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.
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.
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.
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.
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.
4
SHEET METAL HANGER
TAPE
INSULATED VAPOR LINE
A0151-001
TO OUTDOOR UNIT
INSULA TED
VAPOR LINE
CAP
FIGURE 4: Heat Protection
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" for TXV installation.
A0152-001
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.
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.
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.
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.
NOTICE
Johnson Controls Unitary Products
A0153-001