Line Voltage ThermostatWhen determining the best spot for wiring a line voltage thermostat, it is crucial to determine the best spot to get the most accurate read. If your thermostat is located in an area with direct sunlight, or near a heat vent, it will inaccurately read the air temperature, causing your equipment being controlled by the thermostat to run or be shut off when it shouldn’t. Here are some location tips for your line voltage thermostats based on application:

For more information or troubleshooting support, click here to review the instructions.


1. Greenhouse: Your thermostat should be mounted at plant height, near the center of the greenhouse. It should not be directly above heat pipes, in the direct line of a heating duct outlet, or in direct sunlight.
2. HVAC: Your thermostat should be mounted away from heat pipes, heating duct outlets and heat exchange fans.
3. Agriculture: Your thermostat should be mounted out of direct sunlight, and away from any heating elements, including heating duct outlets.
4. Deicer: Your thermostat should be mounted to a post or pole on the top side of your dock, so it can properly read the air temperature.

Proper location is crucial for your thermostat to read air temperature correctly. Mounting your thermostat away from any heating elements or out of direct sunlight will allow your thermostat to function properly.

Now that you know how to do the placement, it’s time to do the wiring!


Line Voltage Thermostat


Most of our line voltage thermostats are wired for heating, unless specified otherwise. When you open the thermostat you should see a white wire that is at blue dot and another wire at the red (heating). The red is your power – do not move this wire. The wire on the blue dot needs to be moved to the yellow dot to be wired for cooling. Continue reading below for more information and illustrations.

All wiring should be done in accordance with applicable codes, ordinances and regulations. Use a disconnect device and overload protection to assure safe installation complying with local and national codes. Figures 1, 2 and 3 illustrate typical wiring for control of heating, cooling, refrigeration, and
combination heating/cooling control systems (use copper conductors only).

General Wiring

Thermostat Wired for Cooling

1. Remove the four screws sec uring the cover to the thermostat, and take the cover off.
2. Connect wires to the appropriate terminals (heating or cooling). See wiring diagrams.
3. Place cover back on thermostat for safety.
4. Connect power supply.
5. Tighten screws on thermostat cover.
6. Turn the dial so that the desired temperature is in front of the pointer.

Checking Wiring

• Turn dial to 110°F. (heating mode) device should come on, (cooling mode) device should be off.

• Turn dial to 30° F. (heating mode) device should cut off, (cooling mode) device should come on.

• As the dial passes current room temperature, you should hear a faint click from the line voltage tstat.

Example Line Voltage Tstat Wiring

Switching Between Heating & Cooling

1. Disconnect the power supply.
2. Remove the four screws securing the cover to the thermostat, and take the cover off.
3. Switching to cooling mode: Remove the wire connected to the heating terminal & connect it to the cooling terminal. Switching to heating mode: Remove the wire connected to the cooling terminal & connect it to the heating terminal.

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Original equipment manufacturers & agricultural communities worldwide use temperature controls designed & manufactured by K-Kontrols. Our temperature controls are great for barns, greenhouses, livestock buildings, garages, vacation homes, construction sites & more.

Custom Options

Variety of custom options available such as temperature ranges, sensing element lengths & private branding.


K-Kontrols meet NEMA 4X, 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.

Made in the U.S.A.

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