Lennox ECB29 Series - User Manual

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Summary

Electric Shock Safety Warnings

Power Disconnection Before Servicing

Ensure all power supplies are disconnected before performing any servicing or maintenance.

Part and Panel Replacement

Verify all parts and panels are correctly replaced before operating the unit.

General Installation and Service Safety

Professional Installation and Service Requirement

Installation and service must be performed by a licensed professional HVAC installer or equivalent service agency.

Handling Precautions

Sharp Edge Hazard and Protective Gear

Handle equipment with care to avoid injury from sharp sheet metal edges; wear gloves and protective clothing.

Shipping and Packing List

Shipping Damage Inspection

Inspect equipment for shipping damage immediately and contact the carrier if damage is found.

Electric Heat Section Description

ECB29 Series Electric Heat Functionality

Describes the ECB29 series electric heat section, its field-installation capability, and single/three-phase availability.

Application Reference

Consult model-specific bulletins for detailed air handler product specification and heat section applications.

General Installation Information

Adherence to Local Codes and Instructions

Follow these general instructions but prioritize local codes and consult authorities before installation.

Power Disconnection and Tool Usage

Always disconnect power before installation/service and use appropriate tools and protective equipment.

Compliance with Industry Standards

Installation must comply with NFPA standards, manufacturer's instructions, and local building codes.

Heat Section Installation Procedures

Pre-Installation Checks

Verify unit rating plate, electrical power availability, and duct clearances before installing the heat section.

Installation Timing Recommendation

Install the electric heat section inside the air handler before the unit is set and the plenum is attached for ease.

Disconnect Power

Ensure all power to the air handler is shut off; multiple disconnects may be necessary.

Remove Access Panel

Take off the air handler's access panel to gain entry for installation.

Remove Knockouts for Heater Installation

Remove the appropriate electric heat knockout from the vestibule panel for heater installation.

Install and Secure Heat Section

Slide the heat section into the air handler, aligning holes, and secure it with provided screws.

Cabinet Modifications for 460 V 3 Ton Models

Modification Requirement

Modifications are needed for 460V ECB29-10F-G/15F-G heat sections in 460V, 3-ton air handlers.

Installation Issue: Restricting Tabs

Tabs on 460V, 3-ton air handlers obstruct the installation of specific ECB29 electric heat sections.

Resolution: Tab Removal

The solution is to remove the identified tabs that are restricting the electric heat section installation.

Electrical Safety Precautions

Grounding and Power Supply Disconnection

Ensure proper grounding and disconnect all remote power supplies before accessing the unit's components.

Circuit Breaker Installation

Mount Circuit Breaker

Install the circuit breaker onto the air handler deck flange using the provided six screws.

Circuit Breaker Orientation for Downflow

In downflow applications, circuit breakers must be rotated 180 degrees to the UP position.

Prepare Access Panel for Breakers

Remove the circuit breaker patch plate from the air handler access panel.

Apply Circuit Breaker Seal

Apply the adhesive-backed seal to the access panel to ensure an airtight fit around circuit breakers.

Install Patch Plate

Break and secure the patch plate to fit the specific size of the electric heat section being installed.

Circuit Breaker Heater and Patch Plate Configuration

Configuration for Small Cabinets

Illustrates circuit breaker and patch plate configurations for specific models in small air handler cabinets.

Common Configurations

Shows typical circuit breaker and patch plate configurations for common electric heat section models.

Circuit Breaker Cover Installation

Surface Preparation for Cover

Clean the surface where the circuit breaker cover will be attached using isopropyl alcohol.

Apply Sealant for Airtight Fit

Apply a thin silicone bead to ensure an airtight seal between the cover and the access panel.

Prevent Condensation in Control Panel

A proper seal prevents warm, moist air from entering the control panel, avoiding condensation.

Electrical Connections and Wiring

Conductor Material Requirement

Ensure that only copper conductors are used for all electrical connections.

Conduit and Wire Sizing

Use 1-1/2 inch conduit; consult unit nameplate and NEC/CEC tables for proper circuit ampacity and protection.

Interface Harness Connection

Disconnect the air handler interface harness and connect the heater plug to the matching indoor plug.

Transformer Installation for 575 V Units

For 575V heaters, connect the provided transformer between the air handler interface harness and its transformer.

Two-Stage Thermostat Wiring

For two-stage thermostats, connect the second-stage heat bulb lead to W2 and remove the R-W2 jumper.

Outdoor Thermostat Wiring

If using an outdoor thermostat, connect leads to W2 and R, removing the R-W2 jumper.

Wiring Connections for Different Heater Types

Connections for Circuit Breaker Heaters

Connect field power supply wiring directly to the circuit breaker(s).

Connections for Terminal Block Heaters

Connect field power supply wiring to the designated terminal block(s).

Connections for Fused Heaters

Connect field power supply wiring to the fuse block for 460V/575V, 3-phase heaters.

Unit Start-Up Procedure

Restore Power and Set Thermostat

Restore power, set the thermostat heat anticipator to 0.4 amps, and set it above room temperature.

Apply Wiring Diagram Sticker

Align and affix the provided wiring diagram sticker to the blower housing.

System Check and Final Setting

Check the system for normal operation and then set the thermostat to the desired temperature.

Air Handler Blower Speed Settings

Blower Speed Adjustment

Adjust blower speed based on the electric heat and air handler unit size; HIGH is the minimum setting.

Typical Unit Applications Wiring

Cooling Application Wiring

Refer to figures for typical field wiring of air handlers with electric heat in cooling applications.

Heat Pump Application Wiring

Refer to figures for typical field wiring of air handlers with electric heat in heat pump applications.

Wiring Diagram Cross Reference

Electric Heat Section Model to Wiring Diagram

Cross-reference table linking specific electric heat section models to their corresponding wiring diagram numbers.

The provided manual describes the installation and features of ECB29 Series Electric Heat Sections, designed for use with various air handler units. These heat sections provide supplemental electric heating for HVAC systems.

Function Description:

The ECB29 series electric heat sections are field-installable components that integrate with air handler units to provide electric heating. They are available in both single-phase and three-phase configurations. Single-phase units are equipped with either terminal blocks or circuit breakers, while three-phase units may utilize fuse blocks. The heat sections are designed to be installed within the air handler's vestibule panel, requiring specific knockouts to be removed for proper fitment, especially for higher wattage units (20kW or 25kW). Once installed, they connect to the air handler's electrical system to provide heat, controlled by the thermostat and integrated with the blower operation. The manual emphasizes the importance of proper electrical connections and cabinet modifications to ensure safe and efficient operation.

Important Technical Specifications:

Voltage: Available in various voltages, including 208-240V (single-phase, 60Hz), 460V (3-phase, 60Hz), and 575V (3-phase, 60Hz).
Phases: Available in single-phase and three-phase configurations.
Wattage: Heat sections are available in various wattages, with specific instructions for 20kW and 25kW units requiring extended width knockouts.
Circuit Protection: Single-phase units come with either terminal blocks or circuit breakers. Three-phase units (460V and 575V) may use fuse blocks, with a transformer provided for 575V units to step down to 460V for the air handler motor and transformer.
Conductors: Requires copper conductors only.
Blower Speed: The minimum blower setting for any air handler size with any heat section in any application is HIGH.
Thermostat Heat Anticipator Setting: 0.4 amps (for electric heat).

Usage Features:

Field-Installable: Designed for easy integration into existing or new air handler units.
Compatibility: Refer to model-specific air handler product specification bulletins for heat section applications.
Two-Stage Thermostat Support: Instructions are provided for connecting two-stage thermostats, including removing jumpers between W2 and R terminals and connecting the second-stage heat bulb lead to W2.
Outdoor Thermostat Support: Instructions for connecting outdoor thermostats, involving removing jumpers between W2 and R terminals and connecting leads to W2 and R.
Blower Speed Adjustment: The blower speed must be adjusted according to the size of the electric heat and air handler unit, with a minimum HIGH setting for all heat sections.
Wiring Diagrams: Comprehensive wiring diagrams are provided for various configurations, including cooling and heat pump applications, and for different motor types (Constant Torque and PSC, Non-Communicating Motors). A cross-reference table links specific electric heat section models to their corresponding wiring diagrams.

Maintenance Features:

Safety First: Emphasizes disconnecting all power supplies before servicing to prevent electric shock.
Professional Installation/Service: Installation, adjustment, alteration, service, or maintenance must be performed by a licensed professional HVAC installer or equivalent, service agency, or the gas supplier.
Grounding: Unit must be properly grounded in accordance with national and local codes.
Access Panels: Requires removal and replacement of air handler access panels for installation and service.
Circuit Breaker Cover: For units installed in unconditioned spaces, a provided circuit breaker cover must be installed using isopropyl alcohol for cleaning and a bead of clear silicone to ensure an airtight seal. This prevents warm, moist air from causing condensation on electrical components.
Regular Checks: After installation, users are instructed to replace the access cover, restore power, set the thermostat anticipator, affix the wiring diagram sticker, set the thermostat above room temperature, check for normal operation, and finally set the thermostat to the desired setting.
Sharp Edges Caution: Users are advised to take care while handling the equipment and wear gloves and protective clothing due to sharp sheet metal edges.

The manual also includes specific instructions for cabinet modifications required for certain 460V, 3-ton models, where tabs on the air handler must be removed to allow proper installation of the electric heat section. Detailed steps for installing circuit breakers, including rotation for downflow applications, and securing patch plates and seals are also provided to ensure proper and safe operation.