American Standard Thermostat ASYSTAT300C Manual

The American Standard ASYSTAT300C is a programmable digital thermostat designed for precise temperature control of residential heating and cooling systems. It features a backlit LCD display, 7-day programming capability, automatic changeover between heating and cooling modes, system status indicators, filter change reminder, and compatibility with most 24VAC HVAC systems. Below are key sections for safety, features, installation, programming, operation, and troubleshooting.

Features at a Glance

Key components: Backlit LCD display, Mode buttons, Fan control, Program/Schedule buttons, Up/Down temperature adjustment, System status indicators.

Installation

Turn off power to HVAC system before installation. Remove old thermostat and prepare wiring.

1. Turn off power: Switch off circuit breaker for HVAC system.
2. Remove old thermostat: Label wires according to terminal markings.
3. Mount new baseplate: Level and secure to wall using provided screws.
4. Connect wires: Insert labeled wires into corresponding terminals (R, C, W, Y, G, etc.).
5. Attach thermostat: Align and snap onto baseplate.
6. Restore power: Turn circuit breaker back on.

WARNING! Electrical shock hazard. Always turn off power before installation. If unsure, consult a qualified HVAC technician.

First-Time Setup

After installation, configure basic settings for proper operation.

1. Insert batteries: Install 2 AA batteries for backup power.
2. Set mode: Press MODE button to select HEAT, COOL, or AUTO.
3. Set fan: Press FAN button for AUTO or ON continuous operation.
4. Set temperature: Use Up/Down arrows to desired temperature.
5. Set clock: Press CLOCK button and adjust time using arrows.
6. Program schedule: Follow programming section to set daily schedules.

CAUTION! Ensure proper wire connections to prevent system damage. Verify system operation after setup.

Specifications

• Power Requirements: 24VAC from HVAC system; 2 AA batteries for backup
• Temperature Range: 40°F to 99°F (4°C to 37°C)
• Temperature Accuracy: ±1°F (±0.5°C)
• Display: Backlit LCD with temperature and status indicators
• Programming: 7-day, 4 periods per day (Wake, Leave, Return, Sleep)
• Compatibility: Single-stage heating and cooling systems (gas, electric, heat pump)
• Wire Terminals: R, C, W, Y, G, O/B (for heat pump systems)
• Operating Environment: 32°F to 122°F (0°C to 50°C)
• Dimensions: 5.5" x 3.5" x 1" (140mm x 89mm x 25mm)

Controls and Settings

Front panel controls: MODE, FAN, HOLD, CLOCK, PROGRAM, Up/Down arrows.

Display Indicators: HEAT, COOL, FAN ON, HOLD, BATTERY LOW, FILTER.

Mode Settings: HEAT (heating only), COOL (cooling only), AUTO (automatic changeover), OFF (system off). Fan Settings: AUTO (fan runs with heating/cooling cycles), ON (continuous fan operation). Programming: Access via PROGRAM button to set 4 time/temperature periods per day. System Settings: Press and hold PROGRAM for 3 seconds to access advanced settings (temperature differential, filter timer, etc.).

Connecting to HVAC System

Match thermostat wires to HVAC system terminals. Common configurations:

1. Conventional Systems: R (24V power), W (Heat), Y (Cool), G (Fan), C (Common)
2. Heat Pump Systems: R, C, O/B (Reversing valve), Y (Compressor), G, W2 (Aux heat)
3. Multi-stage Systems: Additional terminals for W2, Y2 for second stage heating/cooling

Tip: Refer to HVAC system manual or consult technician for proper wiring. Take photo of old thermostat wiring before removal.

Programming Schedule

Create energy-saving schedule with 4 periods per day.

1. Press PROGRAM button to enter programming mode.
2. Select day: Use arrow buttons to choose day or copy to other days.
3. Set Period 1 (WAKE): Enter time and temperature for morning wake-up.
4. Set Period 2 (LEAVE): Set time and temperature for when home is empty.
5. Set Period 3 (RETURN): Set for evening return home.
6. Set Period 4 (SLEEP): Set for nighttime sleeping hours.
7. Repeat for each day or use COPY function for similar schedules.
8. Press DONE to save and exit programming.

Energy Tip: Set temperatures 7-10°F lower when away in winter (higher in summer) to save energy.

Energy Saving Features

Hold/Temporary Override: Press HOLD to maintain current temperature until next scheduled change. Adaptive Recovery: Learns how long system needs to reach set temperature and starts early. Filter Change Reminder: Set timer (30-90 days) to remind when to change HVAC filter. Temperature Limits: Set minimum and maximum temperature limits to prevent extreme settings.

Care & Maintenance

Clean display with soft, dry cloth. Do not use liquids or cleaners. Replace batteries annually or when LOW BATTERY indicator appears. Reset filter reminder after changing HVAC filter.

CAUTION! Do not spray cleaning fluids directly on thermostat. Keep away from direct sunlight, drafts, and heat sources.

Regulatory Information

FCC Part 15: Class B digital device; complies with interference limits for residential use. UL Listed: Meets safety standards for thermostats. Copyright © American Standard Heating & Air Conditioning. For support, visit www.americanstandardair.com or contact 1-800-228-2962. This product may be covered by one or more patents. See website for details.

Troubleshooting

Reset: Remove batteries, turn off power for 30 seconds, then restore to factory defaults.

Service: 1-800-228-2962; www.americanstandardair.com