American Standard HVAC Odyssey TWA1804 D Manual

The American Standard HVAC Odyssey TWA1804 D is a high-efficiency, variable-speed air handler designed for residential and light commercial applications. It features advanced humidity control, quiet operation, compatibility with various American Standard heat pump and air conditioning systems, durable construction, and integrated diagnostic capabilities. Below are key sections for safety, features, installation, setup, operation, and troubleshooting.

1. Features at a Glance 2. Installation 3. First-Time Setup 4. Specifications 5. Controls and Settings 6. Connecting to Systems 7. Operation Modes 8. Maintenance & Service 9. Care & Cleaning 10. Regulatory Information 11. Troubleshooting

Features at a Glance

Key components: Variable-speed ECM blower motor, insulated cabinet, integrated control board, filter rack, condensate drain connection, and electrical access panel.

Feature	Description
Variable-Speed ECM Motor	Provides precise airflow control for enhanced comfort and efficiency
Insulated Cabinet	Reduces operational noise and prevents condensation
Integrated Control Board	Manages blower speed, diagnostics, and system communication
Filter Rack	Accommodates standard 1-inch or 4-inch media filters
Condensate Drain Connection	Includes primary and secondary ports for proper condensate removal
Electrical Access Panel	Secure compartment for wiring and electrical connections
Humidity Control	Automatically adjusts blower speed to manage indoor humidity levels
Quiet Operation	Designed for minimal sound output during all operating modes
System Compatibility	Works with American Standard heat pumps and AC units
Diagnostic LED	Provides status codes for troubleshooting

Installation

Unpack and inspect contents. Ensure installation location is level and accessible.

Position the unit: Place on a level, stable surface or suspend from joists using appropriate hanging brackets.
Connect ductwork: Attach supply and return ducts securely using approved methods and seal all joints.
Make electrical connections: Follow wiring diagram provided; connect to appropriate power supply and thermostat.
Connect condensate drain: Install primary drain line with proper slope; secondary drain is recommended as backup.
Install air filter: Insert appropriate filter into filter rack, ensuring proper direction of airflow.

WARNING! Installation must be performed by a qualified HVAC technician. Disconnect all power before servicing. Ensure proper ventilation and clearances.

First-Time Setup

Power on unit; configure settings via thermostat or dip switches on control board.

Configure thermostat: Set to match system type (heat pump, conventional) and desired fan control (auto/on).
Set blower speeds: Adjust dip switches on control board for cooling, heating, and continuous fan speeds as needed.
Test operation: Initiate cooling and heating cycles to verify proper airflow and temperature delivery.
Check condensate drainage: Verify water flows freely through primary drain line.

CAUTION! Verify all electrical connections are secure and correct before applying power. Incorrect wiring can damage the unit.

Specifications

Model: TWA1804 D
Type: Variable-Speed Air Handler
Voltage: 208/230V, 1 Phase
Motor Type: Electronically Commutated Motor (ECM)
Airflow Range: 400 to 1600 CFM (adjustable)
Filter Size: Accepts 1" or 4" media filters (16x25x1 or 16x25x4 typical)
Cabinet Insulation: 1" thick foam for sound and thermal performance
Sound Rating: As low as 4.5 Sones on low speed
Dimensions (HxWxD): Refer to unit data label
Refrigerant Compatibility: R-410A
Operating Ambient Temp: 55°F to 115°F

Controls and Settings

Primary control is via compatible thermostat. Internal control board manages blower operation.

Thermostat Settings: SYSTEM (Off, Heat, Cool, Auto), FAN (Auto, On). Advanced thermostats may control humidity and variable fan speeds.

Control Board DIP Switches: Adjust for cooling speed, heating speed, continuous fan speed, and thermostat type. Refer to installation manual for switch settings.

Diagnostic LED: Flashes codes to indicate normal operation or fault conditions. Code list is inside access panel.

Connecting to Systems

Compatible with American Standard heat pumps and air conditioners. Requires proper refrigerant line set, electrical, and control wiring.

Turn off power to indoor and outdoor units.
Connect refrigerant lines: Braze liquid and suction lines to factory-provided stubs. Use nitrogen purge during brazing.
Connect control wiring: Run low-voltage wires (typically 18-5 cable) from air handler to outdoor unit and thermostat.
Connect line voltage: Provide correct power supply to air handler and outdoor unit per wiring diagram.

Tip: Label all wires during installation for easier future service. Always use a vacuum pump and micron gauge to evacuate the refrigerant system.

Operation Modes

Operates based on signals from the thermostat.

Cooling Mode: Blower operates at preset cooling speed when thermostat calls for cooling.
Heating Mode (with Heat Pump): Blower operates at preset heating speed when thermostat calls for heat.
Continuous Fan Mode: Blower runs at a low, constant speed to circulate air and filter when FAN is set to ON.
Dehumidification Mode: With compatible thermostat, blower speed reduces during cooling cycles to enhance moisture removal.
System Off: Blower does not operate when SYSTEM is OFF.

WARNING! Do not operate the unit without a filter installed. Restricted airflow can damage the blower motor and reduce efficiency.

Maintenance & Service

Regular maintenance ensures efficiency and longevity.

Monthly: Inspect and clean/replace air filter as needed.
Annually (by technician): Inspect electrical connections, check motor operation, clean blower wheel and drain pan, verify condensate drain flow, and check system pressures and temperatures.

Diagnostic Codes: Refer to service manual for interpreting LED flash patterns for faults like pressure switch error, motor communication error, or over-temperature condition.

Care & Cleaning

Disconnect power before any cleaning. Keep the area around the unit clear.

Exterior: Wipe cabinet with a dry or slightly damp cloth.
Drain Pan & Line: Annually, pour a mixture of water and mild bleach or approved pan tablets through the drain to prevent algae growth.
Blower Assembly: A qualified technician should vacuum the blower wheel and motor during annual service.

CAUTION! Do not use harsh chemicals, solvents, or pressure washers. Do not spray water directly into electrical components.

Regulatory Information

This product complies with applicable U.S. safety and performance standards. The ECM motor contains electronic components that must be disposed of according to local regulations for electronic waste. For technical specifications and warranty information, refer to the original product literature or contact American Standard Heating & Air Conditioning. For support, visit www.americanstandardair.com or contact your local American Standard dealer.

Troubleshooting

Symptom	Possible Cause	Corrective Action
Unit does not start	No power, tripped breaker, faulty thermostat	Check circuit breaker and disconnect switch. Verify thermostat settings and batteries.
Blower runs continuously	Thermostat fan setting on ON, stuck relay	Set thermostat fan to AUTO. If problem persists, contact technician.
Reduced airflow	Dirty filter, blocked ducts, closed registers	Replace filter. Ensure supply registers and return grilles are open and unobstructed.
Water leakage	Clogged condensate drain, disconnected drain line	Clear primary drain line. Ensure drain line has proper slope and is securely connected.
Unusual noise	Loose parts, debris in blower, failing motor	Turn off power and check for loose panels or screws. If noise continues, call for service.
Diagnostic LED flashing	System fault detected	Count the flashes, refer to fault code chart inside unit, and contact a qualified technician.

Reset: For lockout conditions, turn system power off at breaker for 30 seconds, then restore power.

Service: Contact an authorized American Standard dealer. Do not attempt to repair electrical or refrigerant components yourself.