Which Water Heater is Right for You?

Determine Your Hot Water Usage Pattern


First Hour Rating Chart

Typically homeowners fall into three categories when it comes to water usage. Low usage is an estimated 30 gallons/day, Average usage is 64 gallons/day, and High usage is 100 gallons/day.. Use the chart below to help determine your water usage pattern.

My House Has:
Bedrooms: 1 to 1.5 2 to 2.5 3 to 3.5
Bathrooms: 1 to 3 2 to 5 3-5
Suggested First Hour Rating of:
  40-60 (tankless) 60-90 (Tank) 72-70 (Hybrid)
Average Usage Habits Per Hot Water Draw
Use Gallons per use
Shower 7-10
Bath (standard tub) 20
Bath (whirlpool tub) 35-50
Clothes washer
(hot water wash, warm rinse)
Clothes washer
(warm wash, cold rinse)
Automatic dishwasher 8-10
Food preparation and cleanup 5
Personal (hand-washing, etc.) 2

In a recent industry study, the Vertex was tested against a tankless unit in each of the three scenarios. Here are the results:

Usage Water Draw/Day Optimal Unit
Low 30 gallons Tankless
Medium 64 gallons Vertex (Hybrid)
High 100 gallons Vertex (Hybrid)
* GTI Water Heater Comparison Report April 2007

The Vertex (hybrid unit) appears to provide the best all around performance providing the highest delivered efficiency for homes with medium and high usage hot water habits. The tankless appears to be the best option for those in lower demand hot water usage settings.