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HVAC Multimeter Skills: Continuity vs Resistance & Diode Testing

By Roman Baugh

January 7, 2026

Master the critical difference between Continuity vs Resistance testing! This essential HVAC Multimeter Skills training covers proper techniques for diagnosing compressors, motors, and inverter boards, plus essential Diode Testing fundamentals.

What You’ll Learn:

Why continuity mode FAILS for compressor ground testing
The proper resistance range for checking grounded compressors (0-50Ω continuity vs 0-50MΩ resistance)
How to avoid misdiagnosing good compressors as bad
Diode testing fundamentals for inverter board troubleshooting
Proper multimeter selection and settings for HVAC diagnostics

Key Takeaways:

Continuity Mode: For checking circuits that SHOULD be connected (switches, closed contactors, wire continuity)
Resistance Mode: For checking circuits that SHOULD NOT be connected (compressor grounds, motor windings to ground, insulation)

#compressor #compressor diagnosis #continuity #electrical meter #hvac #inverter board #motors #multimeter #resistance

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