Lennox International Inc Lennox Air Handler Installation, Refrigerant Metering Device

If a return air plenum is used, the return air grille should be immediately in front of the opening in the plenum to allow for the free flow of return air. When not installed in front of the opening, there must be adequate clearance around the air handler to allow for the free flow of return air.

Installation

Each unit consists of a blower assembly, refrigerant coil, and controls, in an insulated galvanized steel factory finished enclosure. Knockouts are provided for electrical wiring entrance.

For ease in installation, it is best to make any necessary coil configuration changes before setting air handler in place.

REFRIGERANT METERING DEVICE

CB25UH units are equipped with a factory-installed check expansion valve.

UPFLOW APPLICATION

1.The air handler must be supported on the bottom only and set on solid floor or field‐supplied support frame. Securely attach the air handler to the floor or support frame.

2.If installing a unit in an upflow application, remove the

horizontal drain pan. IMPORTANT - The horizontal drain pan is not required in upflow air discharge installations; its removal provides the best efficiency and air flow.

3.Place the unit in the desired location and slope unit as previously mentioned. Connect return and supply air plenums as required using sheet metal screws.

4.Install units that have no return air plenum on a stand that is at least 14” from the floor. This will allow proper air return.

HORIZONTAL APPLICATIONS

IMPORTANT

When removing the coil, there is possible danger of equipment damage and personal injury. Be careful when removing the coil assembly from a unit installed in right- or left-hand applications. The coil may tip into the drain pan once it is clear of the cabinet. Support the coil when removing it.

ANGLE IRON OR SHEET	ELECTRICAL INLET CLEAR­
METAL MAXIMUM 1/2”	ANCE 4 IN. (102 MM)
LONG SCREW
AIR FLOW
FRONT VIEW	END VIEW

Figure 2. Suspending Horizontal Unit

NOTE — When the unit is installed in horizontal applications, a secondary drain pan is recommended. Refer to local codes.

NOTE — This unit may be installed in left-hand or right-hand air discharge horizontal applications. Adequate support must be provided to ensure cabinet integrity. Ensure that there is adequate room to remove service and access panels if installing in the horizontal position.

LEFT-HAND DISCHARGE

HORIZONTAL DRAIN PAN

IMPORTANT! REMOVE PAN

FOR BEST EFFICIENCY

AND AIR FLOW.

UPFLOW

DRAIN PAN

UPFLOW DRAIN CON­

NECTIONS (BOTH

SIDES; USE ONE SIDE

OR OTHER)

HORIZONTAL DRAIN CONNECTIONS (BOTH SIDES; NOT USED)

1.Determine knockouts required for drain line connections.

2.With access door removed, knock out drain line opening for installing drain lines.

3.Set unit so that it is sloped toward the drain pan end of the unit (see figure 10).

4.The horizontal configuration is shown in figure 3.

AIR FLOW

Drains

KNOCKOUT LEFT‐HAND DRAINS

Figure 1. Upflow Configuration

Figure 3. Left‐Hand Discharge Configuration

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