Lennox Signature XP21 Series Installation And Service Procedure page 18

FLUSHING LINE SET AND INDOOR COIL (2 OF 2)
4
TYPICAL NEW CHECK EXPANSION VALVE INSTALLATION PROCEDURE
THIS OUTDOOR UNIT IS DESIGNED FOR USE IN SYSTEMS THAT USE CHECK EXPANSION VALVE METERING DEVICE. SEE THE LENNOX XP21 ENGI-
NEERING HANDBOOK 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 PROVIDED.
NOTE CONFIRM PROPER THERMAL CONTACT BETWEEN VA-
POR LINE AND CHECK EXPANSION BULB BEFORE INSULATING
THE SENSING BULB ONCE INSTALLED.
B CONNECT THE EQUALIZER
FROM THE CHECK EXPANSION
VALVE TO THE EQUALIZER VAPOR
PORT ON THE VAPOR LINE. FIN-
GER TIGHTEN THE FLARE NUT
PLUS 1/8 TURN (7 FT−LBS) AS IL-
LUSTRATED 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 ILLUS-
TRATED 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 ILLUS-
TRATED IN THE FIGURE TO THE RIGHT.
XP21
THE CHECK EXPANSION VALVE UNIT CAN BE INSTALLED
INTERNAL
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.
STUB
REFER TO BELOW ILLUSTRATION FOR REFERENCE DURING
CHECK
END
INSTALLATION OF CHECK EXPANSION VALVE UNIT.
EXPANSION
VALVE
®
TEFLON
RING
®
TEFLON
SENSING
RING
LINE
LIQUID LINE
ASSEMBLY WITH
BRASS NUT
VAPOR
LINE
LIQUID LINE
LINE
11 12
1
2
10
9
4
8
5
7
6
OR EXTERNAL TO THE
A REMOVE THE FIELD−PROVIDED FITTING THAT TEMPORARY RECON-
NECTED THE LIQUID LINE TO THE INDOOR UNIT'S DISTRIBUTOR AS-
SEMBLY.
B INSTALL ONE OF THE PROVIDED TEFLON
STUBBED END OF THE CHECK EXPANSION VALVE AND LIGHTLY LUBRI-
CATE THE CONNECTOR THREADS AND EXPOSE SURFACE OF THE TEF-
®
LON 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 APPRO-
PRIATELY SIZED WRENCH TO TURN AN ADDITIONAL 1/2 TURN CLOCK-
WISE AS ILLUSTRATED IN THE FIGURE ABOVE, OR 20 FT−LB.
D PLACE THE REMAINING TEFLON
OF THE CHECK EXPANSION VALVE. LIGHTLY LUBRICATE CONNECTOR
THREADS AND EXPOSE SURFACE OF THE TEFLON
FRIGERANT 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
1/8 TURN
BULB
NOTE
3
FLARE SEAL CAP
Page 18
INDOOR COIL. IN
11 12
10
9
8
7
®
RINGS AROUND THE
®
WASHER AROUND THE OTHER END
ON LINES SMALLER THAN
7/8",
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
NEVER MOUNT ON BOTTOM OF LINE.
OR
MALE BRASS EQUALIZER
LINE FITTING
VAPOR LINE
1/2 TURN
1
2
3
4
5
6
®
RING WITH RE-
MOUNT SENSING
FLARE NUT
COPPER FLARE
SEAL BONNET