3 Wire Defrost Termination Switch Wiring Diagram

Having a well-functioning refrigeration system is crucial for any business that deals with perishable goods. One of the vital components of a refrigeration system is the defrost termination switch, which helps regulate the defrost cycle. In this article, we will discuss everything you need to know about the 3 wire defrost termination switch wiring diagram.

What is a Defrost Termination Switch?

A defrost termination switch is a component of a refrigeration system that helps regulate the defrost cycle. It is responsible for signaling the end of the defrost cycle, which helps prevent the refrigeration system from overheating.

The defrost termination switch typically consists of three wires – a common wire, a normally closed wire, and a normally open wire. The switch opens and closes depending on the temperature of the evaporator coil. When the evaporator coil reaches a specific temperature, the switch opens, signaling the end of the defrost cycle.

How Does the Defrost Termination Switch Work?

The defrost termination switch works by monitoring the temperature of the evaporator coil. During the defrost cycle, the evaporator coil is heated to melt any accumulated frost or ice. Once the evaporator coil reaches a specific temperature, the defrost termination switch opens, signaling the end of the defrost cycle.

The defrost termination switch is wired in series with the defrost heater and the defrost thermostat. When the switch opens, it interrupts the power flow to the defrost heater and the defrost thermostat, which effectively ends the defrost cycle.

What is the 3 Wire Defrost Termination Switch Wiring Diagram?

The 3 wire defrost termination switch wiring diagram outlines how to connect the defrost termination switch to the rest of the refrigeration system. The wiring diagram typically consists of three wires – a common wire, a normally closed wire, and a normally open wire.

The common wire is connected to the power source, while the normally closed wire is connected to the defrost heater. The normally open wire is connected to the defrost thermostat. When the defrost termination switch opens, it interrupts the power flow to the defrost heater and the defrost thermostat, which effectively ends the defrost cycle.

Frequently Asked Questions

Question Answer
What happens if the defrost termination switch fails? If the defrost termination switch fails, it can either stay open or stay closed. If it stays closed, the defrost cycle will continue indefinitely, causing the refrigeration system to overheat. If it stays open, the refrigeration system will not be able to defrost properly, causing frost and ice buildup on the evaporator coil.
How often should the defrost termination switch be replaced? The defrost termination switch should be replaced if it fails or if it shows signs of wear and tear. It is recommended that you have a professional inspect your refrigeration system regularly to check for any faulty components.
Can I install the defrost termination switch myself? It is not recommended that you install the defrost termination switch yourself unless you have experience and knowledge of refrigeration systems. It is best to hire a professional to install the switch to ensure that it is done correctly and safely.

Conclusion

The 3 wire defrost termination switch plays a critical role in regulating the defrost cycle of a refrigeration system. It is important to have a solid understanding of the wiring diagram and how the switch works to ensure that the refrigeration system functions properly. If you have any questions or concerns about your refrigeration system or the defrost termination switch, it is best to seek the advice of a professional.