HVAC line voltage thermostat

Tempro HVAC Line Voltage Thermostat products are commonly found in industrial, agricultural and commercial settings to monitor air temperature. The thermostats are either hard wired directly, or use a piggyback plug, to a heat source.  When the air temperature falls within the determined environment, the line voltage thermostat coil senses the temperature change. This in turn triggers the thermostat to operate the heater to eliminate the  freezing temperatures. As the air temperature rises during heater operation, the thermostat returns back to normal. When it does, its will begin shutting the heater down again until temperature falls. To view more detail on our line voltage thermostats, click here.

How Line Voltage Thermostats Work

  • Temperature Sensing: Line voltage thermostats operate based on the principle of temperature sensing. They use a temperature-sensitive element, usually a bimetallic coil or sensor, to detect changes in the room’s temperature.
  • User Settings: The user sets the desired temperature on the thermostat by turning a dial or pressing buttons. When the current temperature in the room deviates from the set point, the thermostat takes action to restore it.
  • Circuit Control: Line voltage thermostats control the flow of electrical current to the heating equipment. When the temperature falls below the set point, the thermostat closes its internal contacts, allowing electricity to flow to the heating element. Conversely, when the temperature exceeds the set point, the contacts open, interrupting the electrical supply.
  • Cycling: The thermostat continually cycles the heating equipment on and off to maintain the desired temperature. As the room temperature approaches the set point, the thermostat reduces or stops the flow of electricity to avoid overheating and maintains a consistent and comfortable environment.

Advantages of Line Voltage Thermostats

  • Compatibility: Line voltage thermostats are suitable for a wide range of heating equipment, making them versatile and adaptable to various heating systems.
  • Direct Control: Since they work with the same voltage as the heating equipment, line voltage thermostats offer precise and immediate control over the heating system, ensuring quick responses to temperature changes.
  • Reliability: These thermostats are known for their durability and reliability, as they have fewer components compared to low-voltage thermostats and are less prone to electronic malfunctions.
  • Cost-Effective: Line voltage thermostats are generally more affordable than their low-voltage counterparts, making them an economical choice for many homeowners.

Line voltage thermostats find applications in a variety of heating systems, including:

  • Baseboard Heaters: They are commonly used in residential spaces and are controlled by line voltage thermostats to maintain room temperatures.
  • Electric Furnaces: These thermostats help regulate electric furnaces, ensuring efficient and consistent heating.
  • Radiant Heating Systems: Line voltage thermostats are ideal for controlling electric radiant floor heating systems, providing even heat distribution.
  • Commercial Spaces: They are widely used in commercial buildings to control electric heaters and other high-voltage heating equipment.

TP 501 two stage thermostat

To have the most accurate temperature reading, it’s best to mount your HVAC line voltage thermostat 5-6 feet above the floor. The reason this is the best location is because it will be exposed to the average temperature of the controlled space. Areas you should not mount the control is where it could be affected by unusual heat or cold temperatures, such as in sunlight, near an entry way, or outside wall.

Tempro thermostats are available with an extended bulb to sense a remote location. These include areas such as for outside air temperature, where the control is located in a safe operating environment.


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Thermostats & Guards

Tempro offers line voltage thermostats & guards commonly found in commercial, industrial and agricultural settings.

Custom Options

Variety of custom options available in both thermostats & guards, such as, temperature ranges, materials, size & private branding.


Tempro products meet NEMA, UL, cUL & NEC 457 Ag-ratings.

High Quality

We take pride in quality control & reliable operation of our components. Every switch is individually tested before it leaves the plant.

Stocked in the U.S.A.

Products are designed & shipped from our facilities in Eau Claire, WI to clients across the globe.