Trane TCONT303 Thermostat Operation Manual

The Trane TCONT303 (XR303 Programmable Thermostat) is a 7-day programmable thermostat for multi-stage 4H/2C heat/cool systems. It features a 3.5-inch backlit LCD display, energy-saving factory schedules with four periods per day (Wake, Leave, Return, Sleep), and adaptive intelligent recovery to reach programmed temperatures on time. Compatible with gas/oil/electric systems, it includes compressor lockout (5-minute minimum off time), air filter reminders, keypad lock, and battery backup. Below are the key specifications and operation instructions.

1. Key Specifications 2. Operation Instructions 2.1. Initial Setup 2.2. Home Screen Navigation 2.3. Scheduling and Presets 2.4. Settings Screen 2.5. Advanced Features 2.6. Troubleshooting 3. Installation Instructions 3.1. Pre-Installation 3.2. Wiring Diagrams 3.3. Configuration Options 4. Calculation Tool

Key Specifications

Operation Instructions

Initial Setup

1. Install Batteries: Pull thermostat from wallplate; insert two AA alkaline batteries (observe polarity). Snap back on. Remove battery tag if present.
2. Set Time: Press Set Time; adjust hour/minute with arrows; press Next for day; press Exit.
3. Set Schedule: Defaults to Energy Star 7-day; press Sched > Edit to customize.
4. System Mode: Press System for Auto/Heat/Off/Cool.
5. Fan Mode: Press Fan for Auto/On.

Home Screen Navigation

1. Display: Inside temp, set temp, mode, fan, schedule (Following/Hold), clock, day.
2. Keys: Fan (Auto/On), System (modes), Sched (scheduling), Hold (overrides), Clock (time), Screen (cleaning lock), More (outdoor temp/humidity/timers).
3. Adjustments: Arrows for temp; hold for permanent hold.
4. Cleaning: Press Screen to lock keys for 30s.

Scheduling and Presets

1. Edit Schedule: Sched > Edit > Select days > Period (Wake/Leave/Return/Sleep) > Set time/heat/cool/fan > Done.
2. Cancel Period: Sched > Edit > Period > Cancel Period.
3. Presets: Sched > Preset > Comfort/Energy Star > Yes to load.
4. Holds: Arrows for temp hold until next period; Hold for permanent; Vacation for days.
5. Recovery: Adaptive: Starts early to reach setpoint (shows "Recovery").

Settings Screen

1. Access Advanced: System (blank keys) > Center key (hold 5s) > "User Setup" > Up arrow to scroll.
2. Options: 0120: Year; 0130: Month; 0140: Day of week; 0150: Date; 0160: Time; 0330: DST (0/1); 0510: Humidifier timer; 0640: Time format (12/24).
3. Reminders: More > Edit > Set filter/UV/humidifier days.
4. Humidity: Arrows for dehum setpoint (select models).
5. Locking: Partial (specific keys) or Full (all); unlock via Advanced.

Advanced Features

1. Humidity/Dehum: Displays RH; set dehum setpoint (AC runs longer if high).
2. Reminders: Filter/UV/humidifier; reset via More > Reset.
3. Adaptive Recovery: Learns over 1 week; no aux heat during recovery.
4. Outdoor Temp: More key (with sensor).

Troubleshooting

Installation Instructions

Warning: Professional installation. Disconnect power.

Pre-Installation

Wiring Diagrams

Terminal Designations:

TerminalDescription
R/RH (4-M-R5)24V Power (Heating)
R/RC-V24V Power (Cooling)
W/H-4Heating Relay
G-FFan Relay
Y-Y6Cooling Relay
OReversing Valve (Cool mode, HP only)
BReversing Valve (Heat mode, HP only)

Notes: Wire condensate switches between Y and Y1. X2 for aux during defrost. Remove jumper for 2-transformer RC/RH. Add for HP. Clip W905 for hydronic.

Configuration Options

  1. Mount base level; connect wires.
  2. Install batteries; snap cover.
  3. Clip jumpers: W904 for °C; W905 for hydronic.
  4. Test: Verify modes/setpoints.

Calculation Tool

Estimate monthly energy savings from scheduling (assumes 1% savings per °F setback; 30 days/month).







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