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Diagnosing and Replacing Mullion/Door Heaters

 

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CONTENT TYPE

VR, ILV, Interactive Modules

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DURATION

1.5 Hours

Target Audience icon

TARGET AUDIENCE

Technician

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COURSE DELIVERY

VR and Web-based

Credits icon

Credits : 0.2

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About the Course:

This Diagnosing and Replacing Mullion/Door Heaters microcredential trains HVAC and appliance technicians to diagnose and replace mullion and door heaters commonly used in refrigeration systems to prevent condensation around door gaskets. Learners will practice identifying faulty heaters, checking continuity and voltage, and safely replacing components to restore proper system performance. The course emphasizes diagnostic precision, safety, and neat workmanship. To learn more and advance your skills, explore our HVAC Certification Training Program.

Learning Objectives:

  • Identify the purpose and operation of mullion and door heaters in refrigeration systems.

  • Diagnose heater faults using multimeters for continuity and voltage checks.
  • Recognize common failure causes such as open circuits, shorted elements, or wiring damage.
  • Safely remove and replace faulty mullion or door heaters following manufacturer specifications.
  • Verify system operation and ensure proper heater function after replacement.

Course delivered via LMS and requires an Oculus VR headset for hands-on VR simulations.

 

Learn to diagnose and replace mullion and door heaters in HVAC systems

 

Workforce Development

HVAC technicians practicing safe replacement of mullion door heaters

At ImmerseLearn, we prepare technicians to perform accurate diagnostics and safe replacements on refrigeration system components. This microcredential emphasizes hands-on troubleshooting and precision repairs.

How this course strengthens workforce skills:

Heater Function and Diagnosis −
Understand how mullion and door heaters prevent condensation and learn to test for voltage and continuity to identify electrical faults.
Failure Mode Identification +
Recognize common issues including open heating elements, broken wiring, and shorted connections.
Replacement Procedures +
Practice removing faulty heaters, routing new wiring, and securing replacements in accordance with manufacturer guidelines.
Operational Verification +
Perform post-replacement checks to ensure proper heater operation and confirm that door seals remain dry and functional.

By completing this microcredential, HVAC technicians will gain the skills to effectively diagnose, replace, and test mullion and door heaters, improving appliance efficiency and reliability. Advance your skills with our HVAC Course for comprehensive hands-on training.