Lennox CBA25UHE Series User Manual

Page 1
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.
NOTICE
A thermostat is not included and must be ordered
separately.
• In non-communicating applications, the Lennox
ComfortSense® thermostat may be used, as well as
other non-communicating thermostats.
In all cases, setup is critical to ensure proper system
operation.
Field wiring for non-communicating applications is
illustrated in diagrams, which begin on page 25.
CAUTION
As with any mechanical equipment, contact with sharp
sheet metal edges can result in personal injury. Take
care while handling this equipment and wear gloves and
protective clothing.
CBA25UHE
IMPORTANT: Special procedures are required for clean-
ing the all-aluminum coil in this unit. See page 25 in this
instruction for information.
Table of Contents
CBA25UHE Unit Dimensions – Upow – inches (mm)...2
CBA25UHE Unit Dimensions – Horiz. – inches (mm) ....3
Specications and Electrical Data ..................................4
Model Number Identication ...........................................5
Blower Data ....................................................................6
Unit Components ............................................................8
ECBA25 Electric Heat Data ............................................9
Heat Section Installation ...............................................13
Conguration Modication ........................................... 15
Brazing Connections ...................................................17
Installing the Condensate Drain ..................................20
Electrical Connections ................................................. 22
Inspecting and Replacing Filters .................................23
Wiring Diagrams ...........................................................23
Professional Maintenance ...........................................25
Check-out Procedures .................................................25
Sequence of Operation ................................................26
Constant Torque Speed Blower Motor (ECM) (B3) ....26
Service Literature
UNIT INFORMATION
100073
July 31, 2023
CBA25UHE (HFC-410A) SERIES UNITS
General Information
This indoor unit with all-aluminum coil is designed for
installation with optional eld-installed electric heat and a
matched outdoor unit that is charged with HFC-410A re-
frigerant. These units, designed for indoor installation in
multiple positions, are completely assembled for upow
and horizontal right-hand discharge before being shipped
from the factory.
All CBA25UHE air handlers are equipped with a facto-
ry-installed, internally mounted check / expansion valve,
which is suitable for use in HFC-410A applications.
This air handler is compatible with the ComfortSense®
non-communicating thermostat and any conventional
non-communicating 24VAC thermostat.
NOTE - For downow or horizontal left-hand air discharge,
certain eld modications are required.

Lennox CBA25UHE Series Specifications

General

Model	CBA25UHE Series
Type	Air Handler
Refrigerant	R-410A
Blower Motor	Variable Speed
Dimensions	Varies by model
Weight	Varies by model
Motor Type	ECM
Heating Options	Electric heat
Voltage	208/230V

Summary

Unit Information and Safety Precautions

General Information

General overview of the air handler unit and its features.

Safety Warnings and Notices

Critical safety alerts for installation, service, and operation.

Upflow Unit Dimensions

Upflow Unit Dimensions and Details

Detailed dimensions, diagrams, and piping plate information for upflow configuration.

Horizontal Unit Dimensions

Horizontal Unit Dimensions and Details

Detailed dimensions, diagrams, and piping plate information for horizontal configuration.

Specifications and Electrical Data

Specifications and Electrical Data Tables

Technical specifications, electrical requirements, and installation clearances.

Optional Accessories List

List of available accessories for the unit.

Model Identification and Airflow Control

Model Number Identification

Explanation of model number coding for CBA25UHE series.

Cooling Blower Speed Settings

Information on blower speed taps and operation.

Blower Performance Data

Air Volume and Wattage Tables (024, 030, 036)

Performance data for CBA25UHE-024, -030, and -036 models.

Blower Performance Data (CBA25UHE-042)

Air Volume and Wattage Tables

Performance data for CBA25UHE-042 model.

Unit Components and Application

Key Unit Components Overview

Description of main parts like control box, coil, and drain pans.

Application Guidelines

Recommendations for unit matching and system setup.

Electric Heat Data (CBA25UHE-024)

Electric Heat Capacity and Requirements

Data for 4-10 kW electric heat kits for CBA25UHE-024.

Electric Heat Data (CBA25UHE-030)

Electric Heat Capacity and Requirements

Data for 4-15 kW electric heat kits for CBA25UHE-030.

Electric Heat Data (CBA25UHE-036)

Electric Heat Capacity and Requirements

Data for 4-15 kW electric heat kits for CBA25UHE-036.

Electric Heat Data and Circuit Breakers

Electric Heat Data (CBA25UHE-042)

Data for 4-15 kW electric heat kits for CBA25UHE-042.

Replacement Circuit Breakers

Catalog numbers for replacement circuit breakers.

Heat Section Installation

Installing the Electric Heat Section

Step-by-step guide for heat section installation.

Changing Circuit Breaker Orientation

Procedure for rotating circuit breakers for proper mounting.

Electrical Connections and Wiring

Circuit Breaker Cover Installation

Instructions for installing circuit breaker covers.

Field Power Supply Wiring

Guide for making electrical power connections.

Configuration Modifications

Upflow Application Configuration

Specific setup and modifications for upflow installations.

Air Handler Speed Adjustments

How to adjust blower speed for electric heat operation.

Horizontal Application Configuration

Horizontal Application Setup

Instructions and considerations for horizontal installations.

Left-Hand Discharge Modification

Steps for configuring left-hand air discharge.

Downflow Configuration and Brazing Safety

Downflow Application Configuration

Specific setup and considerations for downflow installations.

Brazing Connections Warnings

Safety precautions for brazing operations with HFC-410A refrigerant.

Refrigerant Connections and Brazing

Refrigerant Line Set Requirements

Table detailing liquid and vapor line sizes for different models.

Brazing Connections Safety

Warnings related to brazing operations and pressurization.

Brazing Procedures

Detailed Brazing Connections Process

Step-by-step guide for making brazed connections with nitrogen purge.

Condensate Drain Installation

Main and Overflow Drain Setup

Instructions for installing drain pans and lines, including traps.

Duct System and Refrigerant Lines

Duct System Guidelines

Recommendations for duct connections and insulation.

Refrigerant Line Connection Procedures

Steps for connecting refrigerant lines to the coil.

Unit Sealing and Electrical Connections

Sealing the Unit for Air Tightness

Methods to ensure an airtight seal for the unit cabinet.

Making Electrical Connections

Steps for connecting field supply wires to the unit.

Volt Conversion and Filter Maintenance

208 Volt Conversion

Procedure to convert voltage for 208V operation.

Inspecting and Replacing Filters

Guide for filter maintenance and replacement.

Unit Wiring Diagrams

Electric Heat and Air Handler Wiring Diagram

Detailed wiring diagrams for electric heat and air handler connections.

Maintenance and Check-out Procedures

Professional Maintenance

Coil cleaning and general upkeep recommendations.

Check-out Procedures

Steps for verifying system operation after installation.

Sequence of Operation

Cooling and Heating Sequences

How the unit operates in cooling, heat pump, and electric heat modes.

Blower Motor Operation

Constant Torque ECM Motor Operation

Explanation of ECM motor functionality and external static pressure.

Blower Motor Troubleshooting

Checking Motor Voltage Input

Steps for diagnosing 230VAC voltage issues for the motor.

Checking Low-Voltage Communication Input

Steps for diagnosing low-voltage communication issues.

Start-up and Performance Checklist (Upflow)

Upflow Configuration Checklist Items

Detailed checklist items for upflow installation verification.

Start-up and Performance Checklist (Horizontal)

Horizontal Configuration Checklist Items

Detailed checklist items for horizontal installation verification.