Honeywell ST9400C user manual

Yes, the Honeywell ST9400C programmer does have a battery. It is used to maintain the clock and programming settings in case of a power outage. The battery is built-in and not replaceable by the user. It is designed to last for the life of the programmer.

The temperature of the hot water on the Honeywell ST9400C can be adjusted according to your preference. You should refer to the user manual or consult a professional installer for specific instructions on how to adjust the temperature on your particular model, as it may vary.

The Honeywell ST9400A and ST9400C are both programmable timers used for controlling heating systems. However, there are a few key differences between the two models:
1. Mounting Option: The ST9400A is a surface-mounted timer, meaning it is mounted on the wall. The ST9400C, on the other hand, is a backplate-mounted timer, which is typically installed inside the heating system's control panel.
2. Dimensions: The ST9400A is slightly larger in size compared to the ST9400C. The ST9400A measures 150mm x 97mm x 40mm, while the ST9400C has dimensions of 100mm x 75mm x 30mm.
3. Display Type: The ST9400A features a digital LCD display for easy programming and temperature control. In contrast, the ST9400C has a rotary dial and buttons for programming and temperature adjustment.
4. Flexibility: The ST9400C offers more flexible programming options compared to the ST9400A. It allows for different heating schedules for weekdays and weekends, while the ST9400A only offers a single program for each day of the week.
Overall, the main differences between the ST9400A and ST9400C lie in their mounting options, dimensions, display types, and programming flexibility. It is recommended to choose the model that best suits your specific heating system requirements and installation preferences.