Requirements
WARNING
Excessive Weight Hazard - Use two or more people when moving and installing the unit. Failure to do so can result in back or other type of injury.
IMPORTANT
The CBX25UH units are designed to match, and must be used with, outdoor units as rated. The indoor sections are manufactured with a check/expansion valve (TXV) to provide optimum refrigerant control and system performance with a variety of different capacities of out door units.
CAUTION
Physical contact with metal edges and corners while applying excessive force or rapid motion can result in personal injury. Be aware of, and use caution when working near these areas during installation or while servicing this equipment.
These instructions are intended as a general guide and do not supersede local or national codes in any way. Consult authorities having jurisdiction before installation.
Compliance with all local, state, or national codes pertaining to this type of equipment should be determined prior to installation. Read this instruction manual, as well as the instructions supplied in separate equipment, before starting the installation.
In addition to conforming to manufacturer's installation instructions and local municipal building codes, installation of Lennox air handler units (with or without optional electric heat), MUST conform with National Fire Protection Association (NFPA) standards: “Standard for Installation of Air Conditioning and Ventilation Systems” (NFPA No. 90A) and “Standard for Installation of Residence Type Warm Air Heating and Air Conditioning Systems” (NFPA No. 90B).
All models are designed for indoor installation only. The installation of the air handler, field wiring, duct system, etc. must conform to the requirements of the National Electrical Code, ANSI/NFPA No. 70 (latest edition) in the United States, and any state laws, and local ordinances (including plumbing or wastewater codes). Local authorities having jurisdiction should be consulted before installation is made. Such applicable regulations or requirements take precedence over the general instructions in this manual. Install the conditioned air plenum, ducts and air filters (provided) in accordance with NFPA 90B Standard for the Installation of Warm Air Heating and Air-Conditioning Systems (latest edition).
The air handler is shipped from the factory completely assembled. The unit is provided with flanges for the connection of the duct system.
Do not remove the cabinet knockouts until it has been determined which knockouts will need to be removed for the installation.
Select the final air discharge position which best suits the site conditions. Consider required clearances, space, routing requirements for refrigerant line, condensate disposal, filters, duct system, wiring, and accessibility for service. Refer to the air handler rating plate on the air handler for specific information.
WARNING
Danger of explosion. Keep flammable ma terials and vapors, such as gasoline, away from air handler. Place air handler so that heating elements are at least 18 inches (46 cm) above the floor for a garage installa tion. Failure to follow these instructions can result in death, explosion, or fire.
NOTES —
During cooling operation, excessive sweating may occur if the air handler is installed in a warm and humid space.
If installed in an unconditioned space, sealant should be applied around the electrical wires, refrigerant tubing, and condensate lines where they enter the cabinet.
Electrical wires should be sealed on the inside where they exit the conduit opening. Sealant is required to prevent air leakage into, and condensate from forming inside of, the air handler, the control box, and on the electrical controls.
This unit is approved for installation clearance to combustible material as stated on the unit rating plate. Accessibility and service clearances must take precedence over combustible material clearances.
The air handler must be installed so that free access is allowed to the coil/filter compartment and blower/control compartment.
Installation Clearances
NON-DUCTED RETURN CLOSET INSTALLATION The air handler can be installed in a closet with a false bottom to form a return air plenum. It may also be installed with a return air plenum under the air handler.
Louvers or return air grilles are field‐supplied. Local codes may limit application of systems without a ducted return to single story buildings.
When a CBX25UH unit is installed in a closet with a louvered return opening, the minimum open area for the louvers will be:
S320 square inches for -018 and -024 models;
S360 square inches for -030 and -036 models;
S450 square inches for -042 thru -060 models.
If the free area is not known, assume a 25% free area for wood or a 75% free area for metal louvers or grilles. Using the louver dimensions and the 25% or 75% assumption, determine if the open area meets the minimum open area listed above.