In the recent past, a mechanical contractor could install very inefficient appliances and equipment with no thought to energy costs. Energy rates were cheap; therefore, mechanical codes did not address energy usage. Mechanical code emphasis was on installation integrity, clearance to combustibles, and service space requirements. The installed equipment was very heavy and overbuilt. That all changed in the late 20th century due to several economic and environmental factors. These factors created a new buzzword: energy conservation.
Don't wait for an Electrical Inspector to teach you the 2023 NEC. Save time, money, and pass inspections the first time by completing our online continuing education courses.