835965-UIM-C-0814
4
Johnson Controls Unitary Products
PIPING CONNECTIONS
The outdoor condensing unit must be connected to the indoor evapora-
tor coil using field supplied refrigerant grade copper tubing that is inter-
nally clean and dry. Units should be installed only with the tubing sizes
for approved system combinations as specified in tabular data sheet.
The charge given is applicable for total tubing lengths up to 15 feet. See
Application Data Part Number 247077 for installing tubing of longer
lengths and elevation differences.
PRECAUTIONS DURING LINE INSTALLATION
1. Install the lines with as few bends as possible. Care must be taken
not to damage the couplings or kink the tubing. Use clean hard
drawn copper tubing where no appreciable amount of bending
around obstruction is necessary. If soft copper must be used, care
must be taken to avoid sharp bends which may cause a restriction.
2. The lines should be installed so that they will not obstruct service
access to the coil, air handling system, or filter.
3. Care must also be taken to isolate the refrigerant lines to minimize
noise transmission from the equipment to the structure.
4. The vapor line must be insulated with a minimum of 1/2" foam rubber
insulation (Armaflex or equivalent). Liquid lines that will be exposed
to direct sunlight and/or high temperatures must also be insulated.
5. Tape and suspend the refrigerant lines as shown. DO NOT allow
tube metal-to-metal contact. See Figure 2 "Tubing Hanger".
6. Use PVC piping as a conduit for all underground installations as
shown in Figure 3 "Underground Installation". Buried lines should be
kept as short as possible to minimize the build up of liquid refrigerant
in the vapor line during long periods of shutdown
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 application part number 247077 for additional piping informa-
tion.
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 ensure an internally clean and dry system.
PRECAUTIONS DURING BRAZING SERVICE VALVE
Precautions should be taken to prevent heat damage to service valves
by wrapping a wet rag around it as shown in Figure 4 "Heat Protection".
Also, protect all painted surfaces, insulation, and plastic base during
brazing. After brazing, cool joint with wet rag.
The valve can be opened by removing the plunger cap and fully insert-
ing 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. Refer to the Tabular Data Sheet for proper vapor and liquid line siz-
ing.
2. Remove the cap and Schrader core from both the liquid and vapor
service valve service ports at the outdoor unit. Connect low pressure
nitrogen to the liquid line service port.
This system uses R-410A refrigerant which operates at higher pres-
sures than R-22. No other refrigerant may be used in this system.
Gauge sets, hoses, refrigerant containers, and recovery systems
must be designed to handle R-410A. If you are unsure, consult the
equipment manufacturer.
Never install a suction-line filter drier in the liquid line of an R-410A
system. Failure to follow this warning can cause a fire, injury or
death.
Using a larger than specified line size could result in oil return prob-
lems. Using too small a line will result in loss of capacity and other
problems caused by insufficient refrigerant flow. Slope horizontal
vapor lines at least 1" every 20 feet toward the outdoor unit to facili-
tate proper oil return.
FIGURE 2:
Tubing Hanger
NOTICE
A0151-001
SHEET METAL HANGER
LIQUID
LINE
INCORRECT
CORRECT
INSULATED VAPOR LINE
TAPE
FIGURE 3:
Underground Installation
Dry nitrogen should always be supplied through the tubing while it
is being brazed, because the temperature 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.
Do not leave the system open to the atmosphere. Unit damage
could occur due to moisture being absorbed by the POE oil in the
system. This type of oil is highly susceptible to moisture absorp-
tion.
TO INDOOR COIL
TO OUTDOOR UNIT
LIQUID LINE
CAP
PVC
CONDUIT
INSULATED
VAPOR LINE
A0152-001
