Venstar VST3900 Thermostat
The Venstar VST3900 is an enterprise-grade programmable thermostat designed for high-performance multi-stage HVAC systems. As the direct replacement for P374-1500 and P374-1900 legacy units, it offers backward compatibility while upgrading system control. This 7-day programmable digital thermostat supports 3-heat and 2-cool stages, making it compatible with gas/electric or heat pump systems, including those with auxiliary heat. Field technicians value its Dry Contact input, which allows for external control integration, and its ability to support remote sensors for accurate temperature averaging in larger zones. The backlit display provides high-contrast visibility for mechanical rooms, and the non-volatile memory ensures all setpoints are retained during power cycles. Whether you are performing a commercial HVAC thermostat upgrade or a routine maintenance swap, the VST3900 provides the reliable calibration and precision airflow management required for professional installations.
- Universal Compatibility: Supports up to 3-stage heating and 2-stage cooling for maximum application flexibility.
- Seamless Retrofit: Verified as the replacement for discontinued Totaline and Bryant P374 models, ensuring terminal-to-terminal alignment.
- Enhanced Control: Features adjustable deadbands and staging timers to prevent short-cycling and optimize equipment lifespan.
- External Integration: Includes terminals for remote indoor/outdoor sensors and signal inputs for more complex automation requirements.
Common Service Questions
Is the Venstar VST3900 compatible with older P374 series mounts?
While the internal board architectures differ, the VST3900 serves as the direct technical successor for models like the P374-1900, using similar wiring configurations for standard 24V systems.
Does this thermostat require a C-wire for installation?
Yes, for reliable commercial operation and to power the advanced logic board and display, a common wire (C-wire) is necessary.
Can I lock the setpoints to prevent unauthorized adjustments?
The unit includes security features that allow contractors to set restricted setpoint limits or lock the keypad entirely to maintain energy efficiency in commercial spaces.
Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.
Original: $101.04
-65%$101.04
$35.36Venstar VST3900 Thermostat
The Venstar VST3900 is an enterprise-grade programmable thermostat designed for high-performance multi-stage HVAC systems. As the direct replacement for P374-1500 and P374-1900 legacy units, it offers backward compatibility while upgrading system control. This 7-day programmable digital thermostat supports 3-heat and 2-cool stages, making it compatible with gas/electric or heat pump systems, including those with auxiliary heat. Field technicians value its Dry Contact input, which allows for external control integration, and its ability to support remote sensors for accurate temperature averaging in larger zones. The backlit display provides high-contrast visibility for mechanical rooms, and the non-volatile memory ensures all setpoints are retained during power cycles. Whether you are performing a commercial HVAC thermostat upgrade or a routine maintenance swap, the VST3900 provides the reliable calibration and precision airflow management required for professional installations.
- Universal Compatibility: Supports up to 3-stage heating and 2-stage cooling for maximum application flexibility.
- Seamless Retrofit: Verified as the replacement for discontinued Totaline and Bryant P374 models, ensuring terminal-to-terminal alignment.
- Enhanced Control: Features adjustable deadbands and staging timers to prevent short-cycling and optimize equipment lifespan.
- External Integration: Includes terminals for remote indoor/outdoor sensors and signal inputs for more complex automation requirements.
Common Service Questions
Is the Venstar VST3900 compatible with older P374 series mounts?
While the internal board architectures differ, the VST3900 serves as the direct technical successor for models like the P374-1900, using similar wiring configurations for standard 24V systems.
Does this thermostat require a C-wire for installation?
Yes, for reliable commercial operation and to power the advanced logic board and display, a common wire (C-wire) is necessary.
Can I lock the setpoints to prevent unauthorized adjustments?
The unit includes security features that allow contractors to set restricted setpoint limits or lock the keypad entirely to maintain energy efficiency in commercial spaces.
Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.
Product Information
Product Information
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Shipping & Returns
Description
The Venstar VST3900 is an enterprise-grade programmable thermostat designed for high-performance multi-stage HVAC systems. As the direct replacement for P374-1500 and P374-1900 legacy units, it offers backward compatibility while upgrading system control. This 7-day programmable digital thermostat supports 3-heat and 2-cool stages, making it compatible with gas/electric or heat pump systems, including those with auxiliary heat. Field technicians value its Dry Contact input, which allows for external control integration, and its ability to support remote sensors for accurate temperature averaging in larger zones. The backlit display provides high-contrast visibility for mechanical rooms, and the non-volatile memory ensures all setpoints are retained during power cycles. Whether you are performing a commercial HVAC thermostat upgrade or a routine maintenance swap, the VST3900 provides the reliable calibration and precision airflow management required for professional installations.
- Universal Compatibility: Supports up to 3-stage heating and 2-stage cooling for maximum application flexibility.
- Seamless Retrofit: Verified as the replacement for discontinued Totaline and Bryant P374 models, ensuring terminal-to-terminal alignment.
- Enhanced Control: Features adjustable deadbands and staging timers to prevent short-cycling and optimize equipment lifespan.
- External Integration: Includes terminals for remote indoor/outdoor sensors and signal inputs for more complex automation requirements.
Common Service Questions
Is the Venstar VST3900 compatible with older P374 series mounts?
While the internal board architectures differ, the VST3900 serves as the direct technical successor for models like the P374-1900, using similar wiring configurations for standard 24V systems.
Does this thermostat require a C-wire for installation?
Yes, for reliable commercial operation and to power the advanced logic board and display, a common wire (C-wire) is necessary.
Can I lock the setpoints to prevent unauthorized adjustments?
The unit includes security features that allow contractors to set restricted setpoint limits or lock the keypad entirely to maintain energy efficiency in commercial spaces.
Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.
