What Is The Purpose Of An Interlock Circuit On Electric Forced Air Furnace



Heating a home in cold climates can be a challenge. Forced air furnaces are one of the most popular and cost effective ways to heat a home, but they must be properly maintained and operated in order to ensure safety and efficiency. One of the key components of a forced air furnace is an interlock circuit, which is a critical safety measure designed to protect you and your family from potential hazards.

An interlock circuit is a type of electrical circuit that allows two or more devices to interact with each other. In the case of a forced air furnace, an interlock circuit ensures that a variety of safety components are working together to prevent potential fires or other hazardous conditions. It essentially ties together the furnace's blower motor, limit switch, and power switch so they all work together to prevent overheating or other dangerous scenarios.

The purpose of an interlock circuit on an electric forced air furnace is to prevent unsafe conditions from occurring by making sure that the furnace's blower motor and limit switch remain activated until the furnace has reached the proper temperature. This means that the furnace will not start up unless it has reached its optimum operating temperature, ensuring the safety of the occupants in the home. Additionally, the interlock circuit also prevents the furnace from cycling on and off many times in a short period of time, which can cause the furnace to overheat and become a fire hazard.

Although it is possible to build a forced air furnace without an interlock circuit, this is not advisable as it can pose a serious safety risk. Without the interlock circuit, the furnace's blower could start even if the temperature was not yet at the optimum level, potentially leading to a fire. Furthermore, without the interlock circuit, the furnace could cycle on and off multiple times in a short period of time, which could cause the furnace to overheat and become a fire hazard.

In summary, the purpose of an interlock circuit on an electric forced air furnace is to ensure the safety of those living in the home by preventing the furnace from starting up before it has reached its optimum operating temperature or from cycling on and off multiple times in a short period of time. Interlock circuits are a critical safety feature for electric forced air furnaces and should not be ignored.


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