The Honeywell T4 thermostat is a programmable temperature control device available in various versions, including the wireless model T4R and the model with OpenTherm technology T4M.

Where to Buy

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Honeywell T4: Programmable Thermostat

Key Features:

  • Programming: Allows you to set personalized heating schedules.
  • Remote Control (only T4R model): Manage the temperature through a wireless thermostat.
  • OpenTherm Compatibility (only T4M model): Communicates with OpenTherm-compatible boilers for more precise and efficient control.
  • User-Friendly Interface: Easy to use and program.

Simplified Technical Details:

  • T4R: Wireless thermostat, communicates with the boiler via Receiver Box.
  • T4M: Thermostat for OpenTherm boilers, offers advanced temperature control and signals any boiler errors.

Product Information:

  • Brand: Honeywell
  • Model: T4 (also available in T4R and T4M versions)
  • Purchase: Available on Amazon: [product link]

Setting the Current Time on the Honeywell T4 Thermostat

  1. Access Settings: Press the "Menu" or "Settings" button.
  2. Navigate to the Time Menu: Use the directional buttons to find the "Time", "Date & Time" or similar option.
  3. Set the Time: Follow the on-screen instructions to set the current time using the directional and confirm buttons.

Note: Refer to your Honeywell T4 manual (https://homecomfort-techlit.resideo.com/emeadocuments/pim%20-%20renamed/t4-t4r-t4m-gu-it2h32318059-006uk07.pdf) for specific instructions.

Setting Temperatures

To set the comfort and reduced temperatures on the Honeywell T4 thermostat, follow these steps:

  1. Access the Menu: Press the "Menu" button or a similar symbol on the thermostat.

  2. Select "Programming": Use the directional buttons to scroll through the list of options and select "Programming".

  3. Choose the Mode: Choose between "Manual", "Scheduled", or "Automatic" based on your preferences.

    • Manual: Set a fixed temperature by pressing the "+" or "-" button until the desired temperature is reached.
    • Scheduled: Create a schedule with different temperatures at specific times (e.g., 20°C during the day, 18°C at night). The Honeywell T4 thermostat will guide you through setting the times and temperatures for each period of the day.
  4. Confirm Settings: Save the changes by pressing the "OK" button or a similar symbol.

Common Issues with the Honeywell T4 Thermostat

Blank Screen: Check the batteries (T4 and T4R) or verify if the OpenTherm boiler is powered (T4M). Replace the batteries or contact the installer if necessary.

Dead Batteries: Replace the batteries when the screen shows the battery symbol.

Critical Batteries: Immediately replace the batteries if the thermostat flashes the "+" symbol.

The Boiler Won't Turn On: Ensure that the set temperature is higher than the actual room temperature, that the heating system is turned on, and (only for T4R) that the receiver has a wireless signal.

The Heating System Doesn't Respond to Temperature Changes: Verify that the set temperature is higher than the actual room temperature, that the heating system is turned on, and (only for T4R) that the receiver has a wireless signal.

Temperature Sensor Error: Contact the installer to repair or replace the faulty temperature sensor.

Specific Issues with Honeywell T4R (Wireless):

Lost Wireless Signal: Move the thermostat to another location to restore communication if it flashes the "+" symbol and the receiver's LED light flashes red.

No Wireless Connection: Check if the receiver is powered by pressing the button to turn on the boiler. If the receiver is powered but no wireless binding data is stored, follow the pairing procedure described in the installation guide or contact the installer.

FAQ - Frequently Asked Questions about the Honeywell T4 Thermostat

1. How do I replace the batteries in my Honeywell T4 thermostat?

  • Open the battery cover located on the back of the thermostat.
  • Remove the old batteries and insert two new AAA batteries, ensuring they are placed in the correct direction following the + and - symbols.
  • Close the battery cover.

2. What does it mean when the "+" symbol flashes on my thermostat?

The flashing "+" symbol indicates that the batteries are low and need to be replaced immediately.

3. How can I increase or decrease the desired temperature on my thermostat?

Press the "+/-" button on the thermostat to increase or decrease the desired temperature.

4. My T4R thermostat is no longer communicating with the receiver. What should I do?

  • Check that the thermostat's batteries are charged.
  • Move the thermostat to another location to see if the wireless connection improves.

5. How can I program the heating periods on my Honeywell T4 thermostat?

Refer to the user manual (link provided in the description) for detailed instructions on how to set up heating schedules and desired temperatures.

6. What does the "s" symbol flashing on my T4M thermostat mean?

The flashing "s" icon indicates that the OpenTherm boiler has sent an alarm. For more information about the error, refer to the "OpenTherm Boiler Alarms" menu.

7. Can I use the Honeywell T4 thermostat with a non-OpenTherm boiler?

Yes, the Honeywell T4 thermostat can be used with any type of boiler, but the advanced OpenTherm functionalities will only be available if an OpenTherm-compatible boiler is used.

8. What does it mean when the LED on my T4R receiver flashes red?

The flashing red LED indicates that the wireless connection between the thermostat and the receiver has been lost. Try moving the thermostat to another location.

9. How can I manually turn the boiler on/off through the T4R thermostat receiver?

Press the button on the receiver once to manually turn the boiler on or off. When the boiler is on, the LED on the button will be steadily yellow.

10. Where can I find more information and support for my Honeywell T4 thermostat?

Refer to the user manual (link provided in the description) or contact Honeywell customer service for further assistance.

Installation

To correctly install the Honeywell T4 thermostat, carefully follow the instructions provided in the user manual. Ensure you have the necessary tools, such as a screwdriver and a level. Disconnect the power to the heating system before starting the installation. Mount the thermostat on an interior wall, away from heat sources or direct sunlight. Use the level to ensure the thermostat is mounted horizontally. Connect the appropriate cables to the thermostat terminals, carefully following the wiring diagram in the manual. After completing the connection, restore power to the heating system and verify the thermostat is functioning correctly.

Honeywell T4 Technical Specifications

Feature Description
Model Honeywell T4
Type Programmable thermostat
Display Backlit digital
Power Supply Batteries
Features Daily and weekly programming, manual temperature control, vacation mode
Compatibility Traditional heating systems
Additional Options Also available in wireless version (T4R) and with OpenTherm control (T4M)

Honeywell T4 Manual