Dielectric Grease: What It Is, and How To Use It

 

Dielectric grease is an often misused and misunderstood product that could easily benefit HVAC/R technicians in a variety of ways. From food service to electrical connections, dielectric grease can help lubricate mechanical components and prevent corrosion on electrical connections. But we need to understand what it is to begin with, in order to properly apply it in the field.

Dielectric grease is silicone-based grease with insulating properties. Common uses for dielectric grease include electrical connections, spark plug wires, and mechanical connections. The most common misuse of dielectric grease relates to electrical connections.

I mentioned dielectric grease acts as an insulator, yet many technicians mistake silicone grease as conductive. For conductive grease, Conducto-Lube Silver or any carbon conductive grease will do. Conductive grease is for conducting electricity from one conductor through the grease to another conductor. 

 

To apply silicone dielectric grease properly to electrical connections, make sure the conductor mating surfaces are bonded before applying the grease. In coastal climates, low voltage wiring is particularly in danger of corrosion, especially right on the waterfront. 

         

To prevent corrosion and to protect the connections, make a solid connection with your exposed conductor wire with an appropriately sized wire nut. Then remove the wire nut and dip the exposed conductor into dielectric grease. Next, put the wire nut back on. If you really want to get crazy, you can then wrap the connection with electrical tape. For contactors and other connections, wire up the components as usual, then apply a dollop of Daisy…I mean Dielectric grease to the connection points.

         

Dielectric silicone grease can be used in a variety of mechanical applications, as well. The Refrigeration Technologies Silicone Grease is also food-grade and can be used in many refrigeration applications. 

 

Remember to always double-check your electrical and mechanical connections for the correct torque before applying the grease. If you’re not careful, things can get messy quick!

 

-Kaleb

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One response to “Dielectric Grease: What It Is, and How To Use It”

  1. Confused – you note that dielectric grease is non-conductive (insulating), then state to dip exposed (presumed copper) wires in it to help the electrical connection.

    Isn’t conductive grease the appropriate grease in this application? Or is it assumed that the twisted wire formed by linemans/wirenut is forming an adequate connection, and the insulating silicone grease is then added to just keep outside forces (corrosion, arcing) away?

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