Which appliances' contributions are factored into the service load calculations according to Article 230?

The contributions of HVAC systems and water heaters are factored into the service load calculations according to Article 230 of the National Electrical Code. This is important because these systems typically consume a significant amount of electrical power, and their load must be accurately reflected in the service calculations to ensure that the electrical service is adequately sized and can handle peak demand.

HVAC systems, including air conditioning and heating units, are crucial to maintaining comfortable living conditions and can vary widely in their power requirements based on their size, efficiency, and usage patterns. Water heaters also represent a considerable load, especially if they are electric, and often operate during peak times.

By incorporating the load from HVAC systems and water heaters into the service load calculations, the NEC helps to ensure that the electrical service can reliably support essential appliances and systems in a manner that is safe and efficient. This focus on larger, essential appliances distinguishes their load requirements from smaller, less power-consuming devices which are typically not included in the primary service calculations.