Trane TCONT850 Thermostat Operation Manual

The Trane TCONT850 (ComfortLink II XL 850) is a Wi-Fi communicating connected control with a color touch screen for advanced residential HVAC systems. It features support for up to 5 stages heat/2 stages cool, heat pump/dual fuel compatibility, smart optimization, enhanced dehumidification/humidification/ventilation control, Trane Home integration, customizable home screen, 1-Touch Presets, and diagnostic tools. Below are the key specifications and operation instructions.

Key Specifications

• Type: Wi-Fi communicating connected control with color touch screen
• Compatibility:
  • Heat/Cool, Heat Pump, Dual Fuel, Heat Only, Cool Only: up to 5H/2C stages
  • Systems: Trane communicating indoor/outdoor units, Relay Panel for accessories
• Power:
  • AC: 24 VAC (R and C required)
  • Network: Wi-Fi or wired RJ-45
• Temperature Range:
  • Operating/Storage: -40°F to 175°F
  • Humidity: 5% to 95% RH non-condensing
• Operating Conditions: Climate-controlled indoor spaces
• Dimensions: 5-1/2” x 3-3/8” x 1” (WxHxD)
• Features:
  • Color touch screen; Trane Home Wi-Fi integration; Smart Optimization
  • Dehumidification (overcool 0-3°F); Humidifier/Ventilation/Air Cleaner control
  • Fan modes: Auto/On/Quiet; Reminders; USB diagnostics; Stage lockouts
  • Response rates; Blower delays; PI control for efficiency
• Compliance: National, state, local codes; FCC Part 15

Operation Instructions

Initial Setup

1. Power On: Connect to sub-base; screen activates, runs Smart Optimization (blower tests after 18 hrs).
2. Run Wizards: Installation Wizard (system config), User Setup Wizard (date/time, schedules, network).
3. Wi-Fi Setup: Menu > Network; connect to home Wi-Fi for Trane Home.
4. Set Basics: Date/Time, 1-Touch Presets (Home/Away/Sleep).

Home Screen Navigation

1. Display: Customizable widgets (temp, humidity, alerts, outdoor temp); touch for details.
2. Controls: Touch screen for mode/temp adjustments; Menu button for settings.
3. Indicators: System status, alerts, load value, fan mode.

Operating Modes

1. Heat: Select Heat; adjusts stages based on load; flame icon.
2. Cool: Select Cool; activates stages after thresholds; snowflake icon.
3. Off: Select Off; no operation.
4. Auto: Automatic changeover.
5. Emergency Heat: Bypasses compressor for aux heat.
6. Fan: Auto (demand), On (continuous), Quiet (low speed).

Settings Screen

1. Access: Press Menu > Settings.
2. Screen: Brightness, backlight timer, screensaver, color theme, access restrictions (lock/guest).
3. Date & Time: Manual set or auto via Trane Home.
4. Schedules: Guided schedule setup; 1-Touch Presets for Away/Sleep.
5. Security: Screen lock on/off, guest access.
6. Network/Trane Home: Wi-Fi config, account setup.

Advanced Features

1. Smart Optimization: Auto blower tests for accuracy/efficiency.
2. Dehumidification: Overcooling when RH high; set limits.
3. Humidifier/Ventilation: Controls via AUX; timed or with system.
4. Reminders: Filters, UV, maintenance; customizable.
5. Diagnostics: Test modes, save logs to USB.

Troubleshooting

• Display Off: Check 24VAC R-C; power cycle.
  
• No Heat/Cool: Verify modes, lockouts, wiring; run test modes.
  
• Alerts: Check diagnostics for codes; clear or consult dealer.
  
• Wi-Fi Issues: Reconnect network; check Trane Home account.
  
• Erratic: Restore defaults; update software via Trane Home.
  
• Persistent: Contact Trane dealer.

Installation Instructions

Warning: Professional installation. Disconnect power. Comply with codes.

Pre-Installation

• Location: Climate-controlled, good circulation; avoid sun/drafts.
  
• Tools: Screwdriver, level, wire strippers; RJ-45 for wired.
  
• Prep: Ensure 24VAC, Internet access; review system type.

Wiring Diagrams

Terminal Designations (Communicating System w/Relay Panel):

Terminal	Description
R	24VAC Hot
C	Common
BK/R/B	Communicating Bus (to Indoor/Outdoor)
AUX1/AUX2	Accessories (Humidifier/Dehum/Vent via Relay Panel)
ODT	Outdoor Temp Sensor (optional)
RJ-45	Wired Internet

Notes: Use Relay Panel for accessories; specific diagrams for HP/Dual Fuel. Ensure 24VAC between R/C.

Configuration Options

1. Mount sub-base; connect communicating bus and accessories.
   
2. Power up; run Installation Wizard for system/stages.
   
3. Configure Groups: Sensors (ODT), Comfort (dehum), Airflow (delays), Lockouts (temp-based).
   
4. Wi-Fi setup; run tests (blower/stages).
   
5. User Wizard for schedules/presets.

Calculation Tool

Estimate monthly energy savings from Smart Optimization (assumes 0.2 kWh saved per daily test cycle; 30 days/month).