Lennox AC13 -018 Installation Instructions Manual page 13

LIQUID LINE ASSEMBLY
WITH BRASS NUT
(Uncased Coil Shown)
Figure 25. Typical Fixed Orifice Installation
TYPICAL TXV INSTALLATION PROCEDURE
The TXV unit can be installed internal or external to the
indoor coil. In applications where an uncased coil is being
installed in a field−provided plenum, install the TXV in a
manner that will provide access for field servicing of the
TXV. Refer to Figure 26 for reference during installation of
TXV unit.
TWO PIECE
(Uncased Coil Shown)
PATCH PLATE
(UNCASED COIL
ONLY)
LIQUID LINE
ORIFICE
HOUSING
DISTRIBUTOR
TUBES
DISTRIBUTOR
EQUALIZER
ASSEMBLY
LINE
MALE EQUALIZER LINE
FITTING (SEE FIGURE 28
FOR FURTHER DETAILS)
SENSING BULB INSULATION
REQUIRED IF MOUNTED EXTERNAL
TO THE COIL CASING. SEE FIGURE 27
FOR BULB POSITIONING.
Figure 26. Typical TXV Installation
To prevent any possibility of water damage, properly
insulate all parts of the TXV assembly that may sweat due
to temperature differences between the valve and its
surrounding ambient temperatures.
LIQUID LINE
ORIFICE HOUSING
FIXED
ORIFICE
TEFLON
WASHER
LIQUID
LINE
STUB END
TXV
TEFLON
RING
TEFLON
RING
SENSING
LINE
LIQUID LINE ASSEMBLY
WITH BRASS NUT
SUCTION
LINE
LIQUID
LINE
IS
1. Remove the field−provided fitting that temporary
reconnected the liquid line to the indoor unit's
distributor assembly.
2. Install one of the provided Teflon rings around the
stubbed end of the TXV and lightly lubricate the
connector threads and expose surface of the Teflon
ring with refrigerant oil.
3. Attach the stubbed end of the kit valve to the liquid line
assembly. Finger tighten and use an appropriately
sized wrench to turn an additional 1/2 turn clockwise
as illustrated in figure 22, or 20 ft−lb.
4. Place the remaining Teflon ring around the other end
of the TXV. Lightly lubricate connector threads and
expose surface of the Teflon ring with refrigerant oil.
5. Attach the liquid line to the TXV. Finger tighten and use
an appropriately sized wrench to turn an additional 1/2
turn clockwise as illustrated in figure 22, or 20 ft−lb.
6. Attach the suction line sensing bulb in the proper
orientation as illustrated in figure 27 using the clamp
and screws provided.
NOTE − Insulating the sensing bulb once installed may be
required when the bulb location is external to the coil
casing.
SUCTION LINE
BULB
SUCTION LINE
BULB
NOTE − Never mount on bottom of line.
Figure 27. TXV Sensing Bulb Installation
7. Remove and discard either the flare seal cap or flare
nut with copper flare seal bonnet from the equalizer
line port on the suction line as illustrated in figure 28.
IMPORTANT
When removing the flare nut, ensure that the copper
flare seal bonnet is removed.
Page 13
ON LINES SMALLER THAN
7/8", MOUNT SENSING BULB
AT EITHER THE 3 OR 9
O'CLOCK POSITION.
12
BULB
ON 7/8" AND LARGER LINES,
MOUNT SENSING BULB AT
EITHER THE 4 OR 8 O'CLOCK
POSITION. NEVER MOUNT
ON BOTTOM OF LINE.
12
BULB
AC13 SERIES