What is a Limit Switch and Do They Work?

When you set your thermostat to a specific temperature in your home, you may take for granted what goes into keeping it there. Your heating system has a lot of intricate components that work together to heat and cool your home– one of these is the limit switch.

What Is It?

A limit switch is anything that inhibits an electric appliance from performing under specific circumstances. For example, the light that turns on and off in your fridge is a limit switch: the light is prevented from turning on when the door is shut. Another example is your dryer: it won’t operate when the door is opened, a function of its limit switch. Limit switches have three main purposes: to save energy, to keep you safe, and to prevent breakdowns– and the need for costly heating system repairs.

Limit Switches and Furnaces

The limit switch has a sensor in the heat exchanger that determines when the air in your home is warm enough to circulate. Once the air reaches your preset temperature, the limit switch turns on the furnace’s blower– it also turns the blower off when the air temperature drops under a lower limit. For safety, the limit switch turns the burner off when air in the system goes above a maximum temperature. If you notice the furnace turning off too soon– or not soon enough– the limit switch may be broken and in need of furnace repairs.

If you need someone to evaluate your limit switch’s performance or if you have questions about heating system repairs in general, contact Precision Air and Heating. In addition to our expert Phoenix heating repairs, we also offer great deals on comprehensive furnace maintenance and tune-ups that will keep your system running smoothly year-round. For more information on our furnace repairs, replacements, and maintenance plans, call 602-fix-my-ac today, or schedule an appointment online with a Phoenix heating repair specialist.

Precision June 20, 2017


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