Lennox International Inc 15CHAX Series Filters, Supply & Return Duct Connections, Compressors

Filters

Filters are not factory−supplied with the unit; however, optional internally installed filter kits are available. Filter kit 92M54 is used with 2, 2−1/2 and 3−ton units. Filter kit 92M55 is used with 3−1/2, 4 and 5−ton units. The filter kits accommodate the use of 1", 2" or 4" filters. If the optional filter kit is not used, a filter must be field−installed.

Filters must always be installed ahead of evaporator coil and must be kept clean or replaced. Dirty filters will reduce the airflow of the unit. Filter sizes are shown in table 1.

Table 1

Unit Filter Size

Unit Model	Filter Size	Filter Quantity
−24, −30, −36	20 in. X 25 in.	1
−42, −48, −60	16 in. X 25 in.	2

The Healthy Climate® PureAir® air purification system (PCO20−28) may be used with 15CHAX units installed in horizontal air discharge applications only. Installation hardware kit (Y0629) is required to install the PCO20−28 (X8787) in the packaged unit. The PCO20−28 is designed for universal voltage, and is ready to operate at 208/230V. When used, the PCO should be installed before the unit is set in place and before the duct connections are made.

Supply & Return Duct Connections

The duct system should be designed and sized according to the methods in Manual Q of the Air Conditioning Contractors of America (ACCA).

A closed return duct system shall be used. This shall not preclude use of economizers or outdoor fresh air intake. It is recommended that supply and return duct connections at the unit be made with flexible joints.

The supply and return air duct systems should be designed for the CFM and static requirements of the job. They should NOT be sized by simply matching the dimensions of the duct connections on the unit.

Ducting installed outdoors MUST be insulated and waterproofed.

CAUTION

When fastening duct system to side duct flanges on unit, insert screws through duct flanges only. Do not insert screws through casing. Outdoor duct must be insulated and waterproofed.

The 15CHAX unit is shipped ready for horizontal air discharge (side duct connections). If bottom air discharge is desired, the covers must be removed from the supply and return air openings on the bottom of the unit and re−installed to cover the side openings.

	Removing Supply and Return
	Air Opening Covers
	2
	1
1.	Base
2.

Figure 4

The upper return air opening cover must be removed when the PureAir® air purification system (PCO20−28) is being used. In PCO applications, both upper and lower return air openings must be covered by the return air plenum to ensure proper PCO operation. The upper return air opening is not required in horizontal applications when the PCO is not used.

Compressors

Units are shipped with the compressor mountings factory−adjusted and ready for operation.

CAUTION

Do not loosen compressor mounting bolts.

Electrical

All wiring should be done in accordance with the current National Electric Code ANSI/NFPA No. 70 in the United States. In Canada, wiring must be done in accordance with the current CSA C22.2 Part 1. Local codes may take precedence.

Use wiring with a temperature limitation of 75_C min.; run the 208 or 230 volt, 60 hertz electric power supply through a fused disconnect switch to control box of unit and connect as shown in the wiring diagram located on the inside of the control access panel. Refer to figure 5 for electrical access.

Figure 5

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