Installing Indoor Metering Device - Lennox XP16 Series Unit Information

Installing Indoor Metering Device

This outdoor unit is designed for use in systems that use
check expansion valve metering devices at the indoor coil.
See the Lennox XP16 Engineering Handbook for approved
expansion valve kit match−ups. The expansion valve unit
can be installed internal or external to the indoor coil. In
INDOOR EXPANSION VALVE INSTALLATION
TWO PIECE
(Uncased Coil Shown)
PATCH PLATE
(UNCASED
LIQUID LINE
COIL ONLY)
ORIFICE
HOUSING
DISTRIBUTOR
TUBES
DISTRIBUTOR
ASSEMBLY
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.
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.
FLARE SEAL CAP
STUB
CHECK
END
EXPANSION
VALVE
TEFLON
RING
®
TEFLON
SENSING
RING
EQUALIZER
LINE
LIQUID LINE
ASSEMBLY WITH
BRASS NUT
VAPOR
LINE
LIQUID LINE
FLARE NUT
COPPER FLARE
OR
SEAL BONNET
MALE BRASS EQUALIZER
LINE FITTING
VAPOR LINE
Figure 12. Installing Indoor Expansion Valve
applications where an uncased coil is being installed in a
field−provided plenum, install the expansion valve in a
manner that will provide access for field servicing of the
expansion valve. Refer to below illustration for reference
during installation of expansion valve unit.
A Remove the field−provided fitting that temporary
reconnected the liquid line to the indoor unit's distributor
assembly.
B Install one of the provided Teflon
stubbed end of the 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 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
end of the expansion valve. Lightly lubricate connector
LINE
threads and expose surface of the Teflon
refrigerant oil.
E Attach the liquid line assembly to the 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.
SENSING BULB INSTALLATION
A Attach the vapor line sensing bulb in the proper
orientation as illustrated to the right using the clamp and
screws provided.
NOTE Confirm proper thermal contact between vapor line
and expansion bulb before insulating the sensing bulb once
installed.
B Connect the equalizer line from the expansion valve to
the equalizer vapor port on the vapor line. Finger tighten
the flare nut plus 1/8 turn (7 ft−lbs) as illustrated below.
VAPOR LINE
BULB
VAPOR LINE
BULB
NOTE NEVER MOUNT ON BOTTOM OF LINE.
Page 20
®
rings around the
®
washer around the other
®
ring with
ON LINES SMALLER THAN
7/8", MOUNT
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
1/2 Turn
11 12
1
2
10
9 3
4
8
5
7
6
1/8 Turn
11 12
1
2
10
9 3
4
8
7 5
6
SENSING
XP16