NEC 440: Air-Conditioning and Refrigerating Equipment
What This Article Covers
NEC Article 440 covers air-conditioning and refrigerating equipment. It is a specialized supplement to Article 430 — most of the rules use the equipment nameplate ratings instead of motor tables.
Key Requirements
- Conductor sizing based on nameplate minimum circuit ampacity (MCA)
- Disconnect within sight of the AC unit (440.14)
- Short-circuit and ground-fault protection per nameplate maximum overcurrent protective device (MOCP)
- Compressor branch-circuit selection current can be used in place of FLA
- Multi-motor equipment uses 440.33 sizing rules
Common Field Applications
- Wiring a residential 4-ton heat pump
- Installing a packaged rooftop AC unit
- Disconnect for a mini-split outdoor condenser
Common Mistakes & Inspection Failures
- Using motor FLA tables instead of nameplate MCA
- Oversizing breaker beyond nameplate MOCP
- Missing or mislocating the disconnect
Related NEC Articles
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What does NEC 440 cover?
NEC Article 440 covers air-conditioning and refrigerating equipment. It is a specialized supplement to Article 430 — most of the rules use the equipment nameplate ratings instead of motor tables.
What are the key requirements of NEC 440?
Key requirements include: Conductor sizing based on nameplate minimum circuit ampacity (MCA); Disconnect within sight of the AC unit (440.14); Short-circuit and ground-fault protection per nameplate maximum overcurrent protective device (MOCP). See the full requirements list on this page.
What are common mistakes with NEC 440?
Using motor FLA tables instead of nameplate MCA Oversizing breaker beyond nameplate MOCP Missing or mislocating the disconnect
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Michael B.
IBEW Local 134 Journeyman Electrician · Licensed Electrical Contractor
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