| |
 |
| |
 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 GULFWAVE 2 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.
|
| |
 |
| |