1. Introduction
This manual provides detailed instructions for the installation, operation, and maintenance of your GCP T6 Pro Programmable Thermostat, model TH6320U2008. Please read this manual thoroughly before using the thermostat to ensure proper function and to maximize its energy-saving capabilities.
Key Features
- Large, illuminated, easy-to-read display with adjustable idle brightness.
- Multiple programmability modes: 5+2 (weekdays/weekends), 5+1+1 (weekdays/Saturday/Sunday), or 7-Day individual programming, as well as non-programmable operation.
- Pre-set program settings that can be temporarily or permanently overridden.
- Adaptive Intelligent Recovery (optional setting) optimizes start time to reach the desired temperature by the programmed time settings.

Figure 1: Front view of the GCP T6 Pro Programmable Thermostat. The display shows the current temperature setting (72 degrees), the operating mode (Heat), fan status (Fan Auto), and the current time (6:30 PM). Control buttons for Mode, Menu, Fan, and temperature adjustment are visible below the screen.
2. Setup and Installation
Proper installation is crucial for the optimal performance of your thermostat. It is recommended that installation be performed by a qualified HVAC technician.
Power Requirements
The thermostat operates on 24 Volts AC power. Ensure the power supply to your HVAC system is turned off at the circuit breaker before beginning any installation work.
Wiring
Refer to the wiring diagram provided with your thermostat packaging for specific connections. Generally, the thermostat connects to your HVAC system using low-voltage wiring. Incorrect wiring can damage the thermostat or your HVAC system.
Mounting
Mount the thermostat on an interior wall, approximately 5 feet (1.5 meters) above the floor, in an area with good air circulation. Avoid locations near heat sources (lamps, sunlight, fireplaces), drafts (windows, doors), or behind doors.
3. Operation
Display Overview
The large, illuminated display shows the current room temperature, desired setpoint, operating mode, fan status, and time.
- Current Time: Displays the current time.
- Operating Mode: Indicates Heat, Cool, or Off.
- Fan Status: Shows Fan Auto or Fan On.
- Set Temperature: The desired temperature the system is working to achieve.
- System Status: "Following Schedule" indicates programmed operation.
Basic Controls
The thermostat features several buttons for control:
- Mode Button: Press to cycle through system modes: Heat, Cool, Off.
- Fan Button: Press to cycle through fan modes: Auto (fan runs only when heating/cooling) or On (fan runs continuously).
- Menu Button: Accesses advanced settings and programming options.
- +/- Buttons: Adjust the temperature setpoint or navigate menu options.
Setting the Temperature
In Heat or Cool mode, use the + or - buttons to adjust the desired temperature. The new setpoint will be displayed. If a schedule is active, this adjustment will be a temporary override.
Programming Modes
The T6 Pro offers flexible programming options to suit your lifestyle and save energy. Access these settings via the Menu button.
- 5+2 Day Programming: Set different schedules for weekdays and weekends.
- 5+1+1 Day Programming: Set different schedules for weekdays, Saturday, and Sunday.
- 7-Day Programming: Set a unique schedule for each day of the week.
- Non-Programmable: Operates as a manual thermostat, maintaining a single setpoint until changed.
Adaptive Intelligent Recovery
When enabled, Adaptive Intelligent Recovery learns how long it takes your system to reach desired temperatures. It then activates your heating or cooling system earlier to ensure your home reaches the programmed temperature by the scheduled time, rather than starting at the scheduled time. This feature can be enabled or disabled in the thermostat's menu settings.
4. Maintenance
Cleaning the Thermostat
To clean the thermostat, gently wipe the exterior with a soft, damp cloth. Do not use abrasive cleaners or solvents. Avoid spraying liquids directly onto the thermostat.
Battery Replacement (If Applicable)
This thermostat is primarily powered by your HVAC system (24V AC). If your model includes a battery backup for clock retention or specific functions, a low battery indicator will appear on the display. Replace batteries as needed, typically standard AA or AAA alkaline batteries. Refer to the specific instructions for your model if a battery compartment is present.
5. Troubleshooting
If you experience issues with your thermostat, try the following steps before contacting support:
| Problem | Possible Cause | Solution |
|---|---|---|
| No display or unresponsive screen | No power, loose wiring, or tripped circuit breaker. | Check circuit breaker for your HVAC system. Ensure thermostat wiring is secure. If battery-powered, replace batteries. |
| Thermostat not controlling HVAC system | Incorrect mode selected, system power off, or wiring issue. | Verify system mode (Heat/Cool/Off). Check HVAC system power. Inspect wiring for secure connections. |
| Temperature inaccurate | Thermostat location, sensor obstruction. | Ensure thermostat is not exposed to direct sunlight, drafts, or heat sources. Clean any dust from vents. |
| Schedule not working | Schedule not enabled, temporary override active, or incorrect time/date. | Check thermostat menu to ensure schedule is active. Cancel any temporary overrides. Verify current time and date settings. |
6. Technical Specifications
| Specification | Detail |
|---|---|
| Brand | GCP |
| Model Number | TH6320U2008/U |
| Controller Type | Button Control |
| Special Feature | Programmable |
| Voltage | 24 Volts |
| Control Method | Remote (likely refers to app/smart home integration, but based on input, it's "Remote") |
| Style | Modern |
| Backlight | Yes |
| Item Weight | 14.4 ounces (0.9 Pounds) |
| ASIN | B082MQLCZQ |
| Date First Available | December 11, 2019 |
7. Warranty and Support
For warranty information and technical support, please refer to the documentation included with your product packaging or visit the official GCP website. Keep your purchase receipt as proof of purchase for warranty claims.
If you require further assistance, please contact GCP customer service.