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1. Install suction tube adapter.
2. Install liquid flare-to-sweat adapter.
3. Install TXV on liquid flare-to-sweat adapter.
4. Connect external equalizer tube to fitting on suction tube
adapter.
5. Position sensing bulb on horizontal portion of suction tube
adapter. Secure using supplied hardware. Insulate bulb after
installation. (See Fig. 6.)
6. Check all connections for leaks.
FAN COILS
If unit is installed with an 40FKA, FK4 or FC4 fan coil, no TXV
change is necessary since these fan coils are factory-equipped with
proper TXV.
If TXV installation is required, refer to TXV kit Installation
Instructions for details on TXV installation.
Step 7—Make Piping Connections
Relieve pressure and recover all refrigerant before system
repair or final unit disposal to avoid personal injury or death.
Use all service ports and open all flow-control devices,
including solenoid valves.
To prevent compressor damage DO NOT bury more than 36
in. of refrigerant tubing. If ANY tubing is buried, provide
6-in. vertical rise at service valve.
Outdoor units may be connected to indoor section using accessory
tubing package or field-supplied refrigerant grade tubing of correct
size and condition. Tubing diameters listed in Table 1 are adequate
for equivalent lengths up to 100 ft. DO NOT INSTALL EQUIVA-
LENT INTERCONNECTING TUBING LENGTHS GREATER
THAN 100 FT. Do not increase or decrease interconnecting tubing
diameters.
If refrigerant tubes or indoor coil are exposed to atmosphere, they
must be evacuated to 500 microns to eliminate contamination and
moisture in the system.
OUTDOOR UNIT CONNECTED TO FACTORY-APPROVED
INDOOR UNIT
See Product Data Sheet for factory-approved indoor units.
Outdoor unit contains correct system refrigerant charge for opera-
tion with indoor unit of same size when connected by 15 ft of
field-supplied or factory-accessory tubing. Check refrigerant
charge for maximum efficiency.
REFRIGERANT TUBING
Connect tubing to fittings on outdoor unit vapor and liquid service
valves. (See Table 1.) Use refrigerant grade tubing.
SWEAT CONNECTION
To prevent damage to unit or service valves observe the
following:
• Use a brazing shield.
• Wrap service valves with wet cloth or use a heat sink
material.
Service valves are closed from factory and ready for brazing. After
wrapping service valve with a wet cloth, tubing set can be brazed
to service valve using either silver bearing or non-silver bearing
brazing material. Consult local code requirements. Refrigerant
tubing and indoor coil are now ready for leak testing. This check
should include all field and factory joints.
FINAL TUBING CHECK
IMPORTANT:
Check to be certain factory tubing on both indoor
and outdoor unit has not shifted during shipment. Ensure tubes are
not rubbing against each other or any sheet metal. Pay close
attention to feeder tubes, making sure wire ties on feeder tubes are
secure and tight.
Fig. 5—TXV Installed
A91277
THERMOSTATIC
EXPANSION
VALVE
EQUALIZER
TUBE
SENSING
BULB
COIL
Fig. 6—Positioning of Sensing Bulb
A81032
2 O'CLOCK
10 O'CLOCK
SENSING BULB
STRAP
SUCTION TUBE
8 O'CLOCK
4 O'CLOCK
7
⁄
8
IN. OD & SMALLER
LARGER THAN
7
⁄
8
IN. OD
Table 1—Refrigerant Connections and
Recommended Liquid and Vapor Tube
Diameters (In.)
UNIT
SIZE
LIQUID
VAPOR
Connection
Diameter
Tube
Diameter
Connection
Diameter
Tube
Diameter
036, 048
3/8
3/8
7/8
7/8
060
3/8
3/8
7/8
1-1/8
NOTES:
1. Tube diameters are for lengths up to 100 equivalent ft.
2. Do not increase or decrease tubing sizes.
3