A Better Way to Heat Water 

NAECA Guidelines

2015 NAECA


NAECA 2015 Replacement Unit Options






Water Heaters Under 55 Gallons

  • The height of a new unit with the same gallon capacity as an existing unit may be two or more inches taller
  • The diameter of a new unit that has the same gallon capacity as an existing unit may be two or more inches wider
  • For units under 55 gallons, add a minimum of three or more inches when planning the space


Replacement Options
  • For installations where space is not an issue, units of similar gallon capacity but larger in physical size can be installed.
  • For installations where space is an issue, a similar unit with smaller gallon capacity may be installed or a unit with different technology may be a good option.



Water Heaters Over 55 Gallons

  • Water heaters that are larger than 55 gallons will undergo the biggest changes. They may require more space or potentially switching models.
  • All residential electric models over 55 gallons must be of the Hybrid Electric heat pump water heater type design
  • All residential gas models over 55 gallons must be of the condensing water heater type design


Electric Model Replacement Options
  • Hybrid Electric Heat Pump - Designed to dramatically decrease the cost of operation, which translates into significant savings for the homeowner.
  • Two Conventional Electric Models Under 55 Gallons - Installing two smaller standard electric units will not be as energy efficient as a Hybrid Electric for homeowners, but it may be an option in some cases.


Gas Model Replacement Options
  • Our High Efficiency product line comes in multiple sizes and is ideal for delivering large amounts of hot water while providing homeowners with utility savings.
  • Two Conventional Gas Models Under 55 Gallons - Installing two smaller standard gas units will not be as energy efficient as a high efficiency Vertex or tankless for homeowners, but it may be an option in some cases.


Energy Factor Regulations

Rated Gallon Capacity NAECA 2015 Electric NAECA 2015 Gas
30 0.95 0.63
40 0.95 0.62
50 0.95 0.60
60 1.99 0.75
66 1.98 0.75
75 1.97 0.74
80 1.97 0.74
100 1.94 0.72
120 1.92 -

Note: For gas-fired units, NAECA applies only to gas-fired storage heaters below 75,000 BTUs and tankless water heaters below 200,000 BTUs.

Tankless NAECA Minimum Efficiency Standards will remain at the previous rating of .82 EF for all gas tankless units under 200,000 BTUs of input.