American Standard HVAC Odyssey TWA0904 A Manual

The American Standard HVAC Odyssey TWA0904 A is a high-efficiency, 4-ton, 9 SEER residential air conditioning condensing unit designed for reliable cooling performance. It features a durable, corrosion-resistant cabinet, a scroll compressor for quiet operation, and is compatible with matching indoor coils and furnaces. Below are key sections for safety, features, installation, setup, operation, maintenance, and troubleshooting.

Features at a Glance

Key components: Durable galvanized steel cabinet, High-efficiency scroll compressor, Copper tube/aluminum fin coil, Liquid line filter drier, Service valves, Low-pressure switch, High-pressure switch.

Installation

Unpack and inspect unit for shipping damage. Select a level, stable outdoor location with adequate airflow.

1. Prepare the Site: Install on a level concrete pad or approved mounting system. Ensure minimum clearances (24" on all sides, 48" above).
2. Connect Refrigerant Lines: Braze copper lines from indoor coil to unit service valves. Use nitrogen purge during brazing to prevent oxidation.
3. Electrical Connection: Run high-voltage power (208/230V, 1-phase) from disconnect to unit terminal block (L1, L2). Connect low-voltage control wires from indoor thermostat (Y, C).
4. Evacuate and Charge: Evacuate the refrigerant circuit to 500 microns. Charge with R-410A refrigerant according to nameplate and line length.

WARNING! Installation must be performed by a qualified HVAC technician in accordance with all local codes and the National Electrical Code (NEC). Disconnect all power before servicing.

First-Time Setup & Startup

After installation, perform a systematic startup procedure.

1. Pre-Start Check: Verify all electrical connections are tight. Ensure refrigerant charge is correct. Check that fan spins freely.
2. Power On: Restore power at the disconnect and indoor air handler/furnace.
3. Thermostat Call: Set thermostat to "Cool" mode and a temperature below room temp to initiate a cooling cycle.
4. System Check: Listen for compressor and fan start. Verify cool air is delivered indoors. Check operating pressures and superheat/subcooling.
5. Final Settings: Adjust thermostat staging and fan control as needed.

CAUTION! Do not operate the unit without the service panel securely in place. Keep the area around the unit clear of debris and vegetation.

Specifications

• Model: TWA0904 A
• Cooling Capacity: 4 Tons (48,000 BTU/h)
• SEER Rating: 9 SEER
• Refrigerant: R-410A
• Electrical Data: 208/230V, 1 Phase, 60 Hz. Min Circuit Ampacity: 26.1A, Max Fuse Size: 35A.
• Compressor: Scroll, HERmetically sealed.
• Fan Motor: 1/5 HP, PSC.
• Operating Ambient Temp Range: 55°F to 115°F (13°C to 46°C)
• Sound Level: Approximately 78 dB(A) at 3 ft.
• Net Weight: 185 lbs (84 kg)

Controls and Operation

Primary control is via the indoor thermostat. Unit has internal safety and operational controls.

Thermostat Functions: Mode (Cool/Off), Fan (Auto/On), Temperature Setpoint.

Unit Internal Controls: - Contactor: Engages compressor and fan motor upon thermostat call (Y signal). - Capacitor: Provides phase shift for compressor and fan motor startup. - High-Pressure Switch: Opens on excessive discharge pressure, shutting down compressor. - Low-Pressure Switch: Opens on low suction pressure, shutting down compressor. - Time Delay Relay: Prevents short cycling (typically 5-minute off delay).

Operation is automatic based on thermostat demand.

Connecting to Indoor Unit

This unit is designed to be matched with an approved American Standard indoor coil (evaporator) and air handler or furnace.

1. Match System: Consult product literature for approved indoor model pairings.
2. Refrigerant Lines: Connect vapor (suction) and liquid lines between units. Insulate the suction line.
3. Control Wiring: Run 24V control wires. Typically connect Y (cooling) and C (common) from indoor unit terminal board to outdoor unit terminal block.
4. Drain Line: Ensure indoor coil condensate drain line is properly installed and routed.

Tip: Correct refrigerant line sizing and proper insulation are critical for efficiency and capacity.

Maintenance Procedures

Regular maintenance ensures efficiency and longevity. Perform at least annually, preferably before cooling season.

1. Power Off: Turn off power at the disconnect.
2. Clean Coil: Remove debris from around unit. Use a soft brush or low-pressure water spray to clean the condenser coil fins from the inside out. Straighten any bent fins.
3. Check Fan: Inspect fan blade for cracks and ensure it is secure. Lubricate fan motor bearings if not permanently sealed.
4. Electrical Inspection: Check all electrical connections for tightness and signs of overheating.
5. Refrigerant Check: A qualified technician should check operating pressures and refrigerant charge.

WARNING! Do not use high-pressure water or steam on the coil. Do not insert tools into the fan area while power is connected.

Safety Features

Built-in safety controls protect the compressor and system.

• High-Pressure Cut-Out: Protects against over-pressure conditions (e.g., dirty coil, fan failure).
• Low-Pressure Cut-Out: Protects against loss of charge or severe restriction.
• Compressor Overload Protector: Internal thermal protection.
• Time Delay: Prevents rapid compressor cycling.

If unit locks out on a safety, the cause must be diagnosed and corrected before resetting power.

Care & Cleaning

Keep the outdoor unit clean and unobstructed.

Monthly: Visually inspect for debris (leaves, grass clippings) around the cabinet and coil. Remove gently.

Annually: Perform detailed coil cleaning as described in Maintenance.

CAUTION! Never use the unit as a shelf. Do not store chemicals or flammable materials near the unit. Keep lawn sprinklers from spraying directly onto the cabinet.

Regulatory Information

This product complies with applicable U.S. safety and performance standards. The refrigerant, R-410A, is a non-ozone-depleting HFC. Technicians servicing this equipment must be EPA Section 608 certified for handling HFC refrigerants. Disposal must be in accordance with local and federal regulations. For support, contact American Standard Customer Care or visit www.americanstandardair.com. This unit contains materials that may be recyclable. Check with local authorities.

Troubleshooting

Reset: Turning power off at the disconnect for 5 minutes may reset internal safeties.

Service: For technical assistance or warranty service, contact an authorized American Standard dealer or 1-877-467-4289; www.americanstandardair.com