Lennox XC17 Series Unit Information page 16

FLUSHING LINE SET AND INDOOR COIL (2 OF 2)
4
TYPICAL CHECK EXPANSION VALVE INSTALLATION PROCEDURE
This outdoor unit is designed for use in systems that use check expansion valve metering device. See the Lennox XC17 Engineering Hand-
book for approved check expansion valve kit match−ups and application information.
TWO PIECE
(Uncased Coil Shown)
PATCH PLATE
(UNCASED
LIQUID LINE
COIL ONLY)
ORIFICE
HOUSING
DISTRIBUTOR
TUBES
EQUALIZER
DISTRIBUTOR
ASSEMBLY
LINE
MALE EQUALIZER LINE
FITTING (SEE
EQUALIZER LINE
INSTALLATION FOR
FURTHER DETAILS)
SENSING BULB INSULATION IS REQUIRED
IF MOUNTED EXTERNAL TO THE COIL
CASING. SENSING BULB INSTALLATION
FOR BULB POSITIONING.
SENSING BULB INSTALLATION
A Attach the vapor line sensing bulb in the proper orientation
as illustrated to the right using the clamp and screws pro-
vided.
NOTE Confirm proper thermal contact between vapor line
and check expansion bulb before insulating the sensing bulb
once installed.
B Connect the equalizer line from the
check expansion valve to the equalizer
vapor port on the vapor line. Finger tight-
en the flare nut plus 1/8 turn (7 ft−lbs) as
illustrated below.
EQUALIZER LINE INSTALLATION
A Remove and discard either the flare seal cap or flare nut
with copper flare seal bonnet from the equalizer line port
on the vapor line as illustrated in the figure to the right.
B Remove and discard either the flare seal cap or flare nut
with copper flare seal bonnet from the equalizer line port
on the vapor line as illustrated in the figure to the right.
XC17
The check expansion valve 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
check expansion valve in a manner that will provide access for
field servicing of the check expansion valve. Refer to below
STUB
illustration for reference during installation of check expansion
CHECK
END
EXPANSION valve unit.
VALVE
TEFLON
RING
TEFLON
SENSING
RING
LINE
LIQUID LINE
ASSEMBLY WITH
BRASS NUT
VAPOR
LINE
LIQUID LINE
1/8 TURN
11 12
1
2
10
9 3
4
8
5
7
6
A Remove the field−provided fitting that temporary reconnected the liq-
uid line to the indoor unit's distributor assembly.
B Install one of the provided Teflon rings around the stubbed end of the
check expansion valve and lightly lubricate the connector threads and
expose surface of the Teflon ring with refrigerant oil.
C Attach the stubbed end of the check expansion valve to the liquid line
orifice housing. Finger tighten and use an appropriately sized wrench
to turn an additional 1/2 turn clockwise as illustrated in the figure
above, or 20 ft−lb.
D Place the remaining Teflon washer around the other end of the check
expansion valve. Lightly lubricate connector threads and expose sur-
face of the Teflon ring with refrigerant oil.
E Attach the liquid line assembly to the check expansion valve. Finger
tighten and use an appropriately sized wrench to turn an additional 1/2
turn clockwise as illustrated in the figure above or 20 ft−lb.
VAPOR LINE
BULB
VAPOR LINE
BULB
NOTE NEVER MOUNT ON BOTTOM OF LINE.
FLARE SEAL CAP
Page 16
11 12
1
2
10
9 3
4
8
5
7
6
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
12 BOTTOM OF LINE.
BULB
FLARE NUT
COPPER FLARE
OR
SEAL BONNET
MALE BRASS EQUALIZER
LINE FITTING
VAPOR LINE
1/2 TURN