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What is Energy Efficiency Rating

What is Energy Efficiency Rating

All water heaters (tankless or tank storage) are rated as to their “Universal Energy Factor” (UEF). This is a measure of how energy efficient that particular water heater is. It is also one of the factors to go into whether a given water heater qualifies for Energy Star rating.

For example, Energy Star requirements from the Energy Star official website for gas tankless water heaters are:

Criteria Energy Star Requirements
Uniform Energy Factor UEF = 0.87
Maximum Gallons Per Minute Max GPM = 2.9 over a 67°F rise
Warranty Warranty = 6 years on heat exchanger and = 5 years on parts
Safety ANSI Z21.10.3/CSA 4.3

As we see, Energy Star requires not only energy efficiency but also specifies output performance, the minimum warranty, and adherence to certain safety standards.

When you are looking for a tankless water heater, we suggest you choose an Energy Star rated model.

Filed Under: Energy Star Tagged With: Energy Efficiency Ratings

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