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Crankcase Heater Wiring | SureSwitch vs Standard Contactors

By Ty Branaman

November 26, 2025

Master the essentials of crankcase heater wiring in this HVAC training video. Learn how White-Rodgers SureSwitch contactor by Copeland (Model 49M11-843) compares to standard contactors and why proper installation is critical for compressor longevity.

What You’ll Learn:

Why crankcase heaters are essential compressor protection components
Wiring techniques for 1.5-pole and single-pole contactors
How SureSwitch technology prevents arc damage
The difference between standard contactor operation vs advanced switching technology
Testing procedures for crankcase heater circuits
Converting double-pole contactors for proper heater operation

Key Topics Covered:

Standard contactor wiring configurations for crankcase protection
SureSwitch advantages: Short Cycle Timer, brownout protection, arc-free switching
Common wiring mistakes and how to avoid them
Installation torque specs and positioning requirements
Multi-voltage coil applications

#compressor #contactor #crankcase heater #hvac #sureswitch

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