Determine Which NEMA Rating Your Line Voltage Thermostat Should Have

What is nema

In order to determine which NEMA rating your line voltage thermostat should have and where you can mount it, you must first understand its’ NEMA rating, and the differences between ratings.  In this post, we will explain the differences between these ratings. By following our steps, you can ensure you will  purchase the right line voltage thermostat for your application.

Click here to view our collection of NEMA rated Line Voltage Thermostats.

What Is NEMA?

NEMA is described as: standards that are useful in defining the types of environments in which an electrical enclosure can be used” and is defined byWater Heater Line Voltage Thermostat the National Electrical Manufacturers Association. The rating frequently signifies a fixed enclosure’s ability to withstand certain environmental conditions.

All in all, it is important that you purchase the right NEMA rated line voltage thermostat to ensure safe use in the environment you require.  Installing a line voltage thermostat outside that is not high on the NEMA rating scale can cause your thermostat to malfunction or cease to work properly.

Steps determine which NEMA rating your line voltage thermostat should have

    1. First, determine where you want your line voltage thermostat mounted. Do this by looking at its surroundings. For instance, will the thermostat get wet often? Is it exposed to the elements of the outdoors?
    2. Second, determine what NEMA enclosure your thermostat will need. This article by Bud Industries, Inc. is a great guide and does an excellent job of describing different NEMA ratings. 
    3. Third, locate a line voltage thermostat that best fits the NEMA rating you need for your application. You can see our collection of K-Kontrols here.
    4. Finally, remember that it’s ok if you purchase a higher rated NEMA thermostat than you need. Just be sure it’s equal to or above what your application requires. For example, if your application requires a NEMA 3, you can purchase a NEMA 3 OR anything above, but nothing below a 3.

Line Voltage Thermostat Description 

Which NEMA rating your thermostat should have

Line voltage thermostats use a liquid-filled sensing element and capillary. For that reason, they have an exposed or concealed set point dial with adjustable differential, that will switch line voltages.

At K-Kontrol, we offer both a single stage, heat or cool, temperature control and a two stage line voltage thermostat. The two stage line voltage thermostat has two single pole, double throw switches. Each switch uses a liquid filled sensing element and capillary.

Click here to purchase a NEMA rated Line Voltage Thermostat today!

Temperature Differential of Weatherproof Line Voltage Thermostats

Temperature Differential

As you are choosing the best product for your application, you will notice that we talk a lot about temperature differential, or hysteresis, with our line voltage thermostats. So, what is it? When a switch changes states from Open to Closed. The difference between those two points is the differential, or hysteresis. Here’s an example…

A line voltage thermostat kicks your fan on once air temperature rises to 70°F (contacts close), and once the air temperature falls to 65°F the fan turns off (contacts open). Given this example, the differential of the line voltage thermostat is 5°F.

Line Voltage Thermostats Differential

Our line voltage thermostats are available with a fixed temperature differential of 2°F.

Our Tempro brand of line voltage thermostats offer an adjustable differential up to 12°F.

Additionally, our electronic temperature controller offers an adjustable differential up to 30°F.

For more information about differential and/or our thermostat products, click here or contact us at 715-831-6353.

Wiring a Line Voltage Tstat

The K-Kontrol line voltage tstat is designed for reliable use in heating, ventilating and refrigeration applications. The thermostat has three contact points. Most of our 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.

WIRING IMPORTANT

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

1. Remove the four screws securing 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 WiringThermostat Wired for Cooling

• 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.

Switching Between Heating & CoolingExample Line Voltage Tstat Wiring

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.

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

Portable Line Voltage Thermostat Piggyback Plug

Portable PreWired Thermostat

Portable Line Voltage ThermostatCertain K-Kontrol thermostats are supplied with a cord and series plug for easy connection to a 120V AC grounded receptacle. Hang the portable line voltage thermostat near a 1 20V three prong receptacle with a ground pin using the hanging wire included in the package. Plug the male prongs into the receptacle and then plug the controlled equipment into the female part of the plug. If an extension cord is required use only one with a grounded 3 prong plug and 14 gage wire.

Three different varieties are available for purchase online. Click here to learn more!

The K-Kontrol portable line voltage thermostat creates an easy plug-and-play solution. These thermostat controllers are commonly found in barns, greenhouses, garages, vacation homes, construction sites, RV’s, basements, computer rooms and more. They aren’t effected by surges, lightning strikes or power outages like a digital thermostat. It can be used anywhere you have a 120 volt outlet as the clear cover protects from weather and damage.

For more information about our Portable line voltage thermostats, click here!