Lennox CBA25UH

©2017 Lennox Industries Inc.
Dallas, Texas, USA
Page 1
THIS MANUAL MUST BE LEFT WITH THE
HOMEOWNER FOR FUTURE REFERENCE
WARNING
Improper installation, adjustment, alteration, service
or maintenance can cause property damage, personal
injury or loss of life. Installation and service must be
performed by a licensed professional HVAC installer or
equivalent, service agency, or the gas supplier.
IMPORTANT
The Clean Air Act of 1990 bans the intentional venting of
refrigerant (CFCs, HCFCs and HFCs) as of July 1, 1992.
Approved methods of recovery, recycling or reclaiming
must be followed. Fines and/or incarceration may be
levied for noncompliance.
INSTALLATION
INSTRUCTIONS
MULTI-POSITION AIR HANDLERS
507751-01
12/2017
Merit
®
Series
CBA25UH Air Handler Units
Shipping and Packing List
Package 1 of 1 contains:
1 – Assembled air handler unit factory-equipped for upow
or horizontal air discharge application (includes upow
and horizontal drain pans and preinstalled air lter).
Check the air handler for shipping damage; if found, im-
mediately contact the last carrier. Check the unit rating
plate to conrm that delivered unit matches order.
IMPORTANT: Special procedures are required for clean-
ing the all-aluminum coil in this unit. See page 18 in this
instruction for information.
IMPORTANT INFORMATION FOR INSTALLER
This unit has a delay relay that delays the supply blower “ON” for 1 second and keeps the blower “ON” for 45
seconds on all fan and cooling demands. For more details, refer to page 17 for unit sequence of operation.
1
SECOND
DELAY
OFF
100%
CFM
100%
CFM
45
SECS
COOLING
DEMAND
1
2
34
Table of Contents
Shipping and Packing List .............................................1
CBA25UH Unit Dimensions – Upow – Inches (mm) .....2
General Information .......................................................3
Requirements ................................................................3
Installation Clearances ..................................................4
Installation .....................................................................4
Condensate Drain...........................................................7
Duct System and Filters ...............................................8
Brazing Refrigerant Lines .............................................. 9
Sealing the Unit ...........................................................12
Electrical Connections ................................................. 12
Air Flow – Cooling Blower Speed ................................ 15
Check-out Procedures .................................................16
Operation ....................................................................17
Homeowner Maintenance ............................................17
Repairing or Replacing Cabinet Insulation ..................18
Professional Maintenance ...........................................18
Use of Air Handler During Construction .......................18

Lennox CBA25UH Specifications

General

Type	Air Handler
Brand	Lennox
Model	CBA25UH
Refrigerant	R-410A
Nominal Cooling Capacity	1.5 to 5 tons
Airflow	Up to 2000 CFM
Cabinet Material	Galvanized Steel
Width	21 inches
Motor Type	PSC
Warranty	5-Year Limited Warranty on Covered Components
Voltage	208/230V
Weight	Variable
Energy Efficiency	High

Summary

Shipping and Packing List

CBA25 UH Unit Dimensions

Upflow Configuration and Piping Plate Details

Provides dimensions for the unit in upflow configuration and details of the piping plate.

General Information

Requirements and Codes

General requirements and applicable codes for installation and system operation.

Installation Clearances

Non-Ducted Return Closet Installation

Clearance requirements for installing the air handler in a closet without a ducted return.

Installation Procedures

Refrigerant Metering Device

Details about the factory-installed check/expansion valve for refrigerant control.

Upflow and Horizontal Application Notes

Instructions for upflow setup and considerations for horizontal installations.

Horizontal Discharge Configurations

Right-Hand Discharge

Instructions for configuring the air handler for right-hand discharge.

Left-Hand Air Discharge Modifications

Field modifications required for horizontal left-hand air discharge configurations.

Left-Hand Discharge and Downflow Setup

Left-Hand Discharge Conversion

Detailed steps for converting the unit to left-hand discharge.

Downflow Application Notes

Notes and instructions for installing the air handler in a downflow configuration.

Condensate Drain System

Overflow Drain Line and Unit Sloping

Details on overflow drain line installation and proper unit sloping for drainage.

Condensate Drain Testing

Drain Testing Procedures

Procedures for testing the installed condensate drain pan and line for leaks and proper flow.

Duct System and Filters

Duct System Requirements

Requirements for supply and return duct systems, including insulation and sizing.

Air Filter Selection

Information on air filter sizes and selection for the air handler unit.

Brazing Refrigerant Lines

Refrigerant Line Routing and Protection

Brazing Connections and Process

Sealing the Unit

Electrical Connections

General Electrical Safety and Standards

Covers electrical connection safety, wiring standards, and general precautions.

Voltage Conversion and Panel Relocation

208 Volt Conversion

Procedure for converting the unit's voltage from 240VAC to 208VAC.

Control Panel Relocation

Instructions for relocating the control panel for specific configurations.

Electric Heat Wiring Diagram

Blower Speed Adjustment

Changing Blower Motor Speed

Instructions for changing the blower motor speed for optimal airflow.

Low Voltage Thermostat Connections

Blower Performance Data

Check-out Procedures

Pre-Start-Up Checks

List of essential checks to perform before starting up the air handler system.

System Operation Modes

Time Delay, Cooling, and Heating Operation

Explains operation sequences for cooling, electric heat, heat pump, and emergency heat.

Homeowner Maintenance

Guidance for homeowners on maintaining the air handler unit, focusing on filters.

Repairing Cabinet Insulation

Damaged Insulation Repair

Procedures for repairing or replacing damaged insulation within the air handler cabinet.

Professional Maintenance

Use of Air Handler During Construction

Start-up and Performance Checklist (Upflow)

Start-up and Performance Checklist (Horizontal)