Lennox International Inc 506945-01 Refrigerant Piping -- Installing Indoor Expansion Valve

STEP 2 -- REFRIGERANT PIPING -- Installing Indoor Expansion Valve

This outdoor unit is designed for use in systems that use either an fixed orifice (RFC) (included with outdoor unit), or expansion valve metering device (purchased separately) at the indoor coil. See the 13ACX Product Specifications bulletin (EHB) for approved expansion valve kit match ups. The 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 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. After installation of the indoor coil metering device, proceed to Step 5.

INDOOR EXPANSION VALVE INSTALLATION

TWO-PIECE		(Uncased Coil Shown)
PATCH PLATE
(UNCASED				STUB
COIL ONLY)	LIQUID LINE
				END
		ORIFICE			EXPANSION
		HOUSING
DISTRIBUTOR					VALVE
TUBES						TEFLON®
						RING
				TEFLON®		SENSING
				RING
						LINE
DISTRIBUTOR			EQUALIZER
ASSEMBLY			LINE
					LIQUID LINE
					ASSEMBLY WITH

CInstall one of the provided Teflon® rings around the stubbed end of the expansion valve and use refrigerant

oil to lightly lubricate the connector threads and ex­ posed surface of the Teflon® ring.

DAttach the stubbed end of the expansion valve to the liquid line orifice housing. Finger tighten, then use an appropriately sized wrench to turn an additional 1/2 turn clockwise as illustrated in the figure to the right, or tighten to 20 ft-lb.

EPlace the remaining Teflon® washer around the other

end of the expansion valve. Lightly lubricate connector threads and expose surface of the Teflon® ring with refrigerant oil.

FAttach the liquid line assembly to the expansion valve. Finger tighten, then use an appropriately sized wrench to turn an additional 1/2 turn clockwise as illustrated in the figure above or tighten to 20 ft-lb.

1/2 Turn

11 12		1
10		2
9		43
8 7	6	5

		BRASS NUT
MALE EQUALIZER LINE	VAPOR
FITTING (SEE
	LINE
EQUALIZER LINE
INSTALLATION FOR
DETAILS)
Sensing bulb insulation is required if
expansion valve is installed external to the		LIQUID LINE
coil casing. See sensing bulb installation for
bulb positioning.

SENSING BULB INSTALLATION

AAttach the vapor line sensing bulb in the proper orienta­ tion as illustrated below using the clamp and screws provided.

BNOTE - Though it is preferred to have the sensing bulb installed on a horizontal run of the vapor line, installation on a vertical run of piping is acceptable if necessary.

NOTE — Confirm proper thermal contact between vapor line and expansion bulb before insulating the sensing bulb.

CConnect the equalizer line from the expansion valve to the equalizer vapor port on the vapor line. Finger tighten the flare nut, then tighten an additional 1/8 turn (7 ft-lbs) as illustrated to the right.

	1/8 Turn
	11 12		1
10			2
9			43
8	7	6	5

EQUALIZER LINE INSTALLATION

ARemove 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 below.

BRemove the field-provided fitting that temporarily reconnected the liquid line to the indoor unit's distributor assembly.

FLARE SEAL CAP		FLARE NUT
	OR	COPPER FLARE
		SEAL BONNET
		MALE BRASS EQUALIZER
		LINE FITTING
		VAPOR LINE

VAPOR LINE

12

BULB

VAPOR LINE

12

BULB

ON LINES SMALLER THAN 7/8”, MOUNT SENSING BULB AT EITHER THE 3 OR 9 O'CLOCK POSITION.

BULB

ON 7/8” AND LARGER LINES,

MOUNT SENSING BULB AT

EITHER THE 4 OR 8 O'CLOCK

POSITION. NEVER MOUNT

THE SENSING BULB ON

BOTTOM OF LINE.

BULB

NOTE — NEVER MOUNT THE SENSING

BULB ON BOTTOM OF LINE.

FIGURE 10

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