GulfWave2 Model Selector: Which Model is Right for You?

Choosing an appropriate model of electric tankless water heater for your home or business depends on 3 primary factors:

1.) incoming water temperature

2.) maximum flow rate desired

3.) the electrical service of your home.

Incoming Water Temperature

The chart on the right is designed to offer you a general model recommendation based on the typical winter incoming water temperatures in various regions of North America. The model recommended on the chart for your area is based on a desired maximum flow rate of about 3 gallons per minute and should be regarded as the smallest recommended model for a general whole-house residential water heater – selecting a more powerful model will provide higher flow rates. Our chart and recommendations also assume that your home has enough electrical service to support the model suggested. - see charts.

Maximum Flow Rate Desired

Before making a decision on a tankless water heater model, you should consider the maximum flow rate of hot water you really need. Most people tend to over-estimate their simultaneous hot water demand. See the chart below for a few flow rate guidelines for various hot water applications in the home.

Most homes may only demand one major hot water use at a time, or a maximum of 2 flow restricted showers used simultaneously. Generally, a maximum flow rate of 3 GPM will be sufficient for such applications. You are encouraged to measure the flow rates at your showerhead and various outlets in the home to get a more definitive estimate of your true flow rate needs. In warmer climates, it is possible to use one of our more powerful models to run flow rates of up to 7 gallons per minute and still achieve a comfortable output temperature suitable for multiple applications (see chart). However, in northern climates, your flow rate expectations should be lower (up to 3.5 GPM), depending on your incoming water temperature. You could achieve a comfortable output temperature suitable for one or two applications. (see chart) In colder climates, to achieve greater than 3.5 gpm flow rate, the installation of two tankless units would substantially increase your hot water supply.
 
The following chart illustrates the maximum flow rate that can be achieved with each model based on a 110°F output temperature. Most people shower at a temperature of between 98° and 104°F. This chart is based on a 240 volt input voltage and maximum flow rates are listed for various incoming water temperature levels. If your home or business has less than 240 volt power (208v), your maximum flow rate will be lower. Simply look up your incoming water temperature and desired flow rate to determine your model choice. Don't forget that incoming water temperature may change throughout the year depending on the season.

Generally speaking, in the chart, areas shaded in dark grey are suitable only for small point-of-use applications (a single sink for instance). Areas shaded in light grey may be suitable for homes with modest hot water needs and that use flow restricted showerheads. Very careful measurement of your actual water flow rate and incoming water temperature are recommended before making a final model selection. Areas shaded in red represent the best model choices for general whole-house water heating demands. Areas indicating a maximum flow rate of 4.0 gallons per minute or more are generally satisfactory for running 2 showers at a time with standard showerheads.
 
Please note that your incoming water temperature could vary significantly from other homes in your immediate area, so checking your incoming water temperature is generally a more accurate means of determining which model is best suited to your home or business.

Electrical Service

Your final consideration when selecting an electric tankless water heater is the electrical service to your home or business. All GULFWAVE2 tankless water heaters require 240 volts, single phase power. Since a tankless water heater works on demand, it must transfer a massive amount of heating power instantaneously to the water heating elements. Accordingly, consideration must be given to the number of AMPS of electrical service your home has to support the operation of the heater and other simultaneous electrical needs. You can determine how many amps of electrical service your home has by inspecting the main breaker (the one you use to turn off power to the whole house) in your electrical panel.

GulfWave2: Model G-11

Model G-11 11kw tankless water heater is designed for moderate climates where the lowest incoming water temperature is above 70 degrees. The model G-11 is a POINT OF USE or booster model in warm climates as opposed to a whole house water heater.

GulfWave2: Model G-14

Model G-14 --- 14kw tankless water heater is configured for climates where the lowest incoming water temperature is above 70 degrees. The model G-14 is used primarily in warm climates as a whole house unit accommodating 1.0 to 1.5 bathroom dwellings.

GulfWave2: Model G-16

Model G-16 --- 16kw tankless water heater is designed for moderate climates where the coldest incoming water temperature is 60 degrees or greater. As a whole house model, the G-16 is best suited to homes in the southernmost regions of the U.S. (i.e. Southern California, Texas, Florida, etc.) as well as Mexico, and the Caribbean. This model is used for homes with 1.5 to 2.5 bathrooms throughout the southern regions of the U.S.

GulfWave2: Model G-18

Model G-18 --- 18kw tankless water heater is configured for climates where incoming water temperatures are in the 60 to 70 degree range. As a whole house model, the G-18 is used in homes with 2.5 to 3.5 bathrooms.

GulfWave2: Model G-21

Model G-21 --- 21kw tankless water heater is configured for cold climates where the incoming water temperature can drop below 55 degrees. The G-21 model is well suited for homes in the northern U.S. and Canada, and those in the southern U.S. that have large Roman-style or Jacuzzi tubs and that have generally more demanding water usage needs.

GulfWave2: Model G-24

Model G-24 --- 24kw water heater is configured for climates where incoming water temperatures are in the 50 to 70 degree range. The Model G-24 is suitable as a whole house water heater with more than 3.5 bathrooms in warmer climates; or smaller applications in colder climates.

GulfWave2: Model G-27

Model G-27 --- 27KW is the most powerful electric tankless water heater on the market. It is configured for cold climates where the incoming water temperature can drop below 45 degrees. The Model G-27 is well suited for homes in the northern U.S. and Canada, and those in the southern U.S. that have large Roman-style or Jacuzzi tubs that have generally more demanding water usage needs.

**All units come equipped with an approved sub-panel, breakers and stainless water heaters hoses with compression fittings.

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