Selecting A Tankless Water Heater: Assessing Location, Size And Demand

Selecting A Tankless Water Heater: Assessing Location, Size And Demand

Does your Metro-East home require a new water heater?  Don’t overlook the potential benefits that a tankless water heater provides when exploring various systems. When you’re evaluating tankless systems, you’ll need to know how to assess location, size and demand, in order to select a water heater that will suit your needs.
First of all, however, it’s important to realize the difference between a tankless, or demand, water heater and a traditional storage water heater. A tankless unit will heat the water on demand, either with electricity or gas, and doesn’t require a tank to store the heated water. As long as it’s sized properly, it will continue to supply heated water, without depleting what’s being stored in a tank.


A tankless water heater of the right size can satisfy the water-heating needs of an entire house, though if it’s too small, it will have trouble supplying water for multiple uses. Some homeowners go ahead and install two or more units at strategic points in the home, in order to satisfy different needs.


Once you know the locations that a tankless water heater will supply, you can begin to select the size of the system, based on demand. This process involves calculating the flow rate of the various hot water uses in your home, via gallons per minute (GPM). For instance, the typical shower requires up to 3 GPM, while a bath requires 4 GPM. Once you add up the uses that you require, you can select a system that can meet that demand.


Other sizing factors include the system’s temperature rise. Every home has a main supply of incoming water that’s a particular temperature. Heat must be added to this water to create hot water for washing clothes and hands, for instance. You can generally find systems with varying temperature rises to meet the particular needs of the application. It’s often best to have an expert HVAC contractor assist you in making these calculations.

Take your home’s hot water heating to the next level with a new tankless water heater. When selecting one or more tankless water heaters, keep in mind location, demand and sizing. Contact Ernst Heating & Cooling for help during the selection and installation process.

Our goal is to help educate our customers about energy and home comfort issues (specific to HVAC systems).  For more information about tankless water heaters and other HVAC topics, visit our blog.

Ernst Heating & Cooling services Hamel, Illinois and the surrounding areas

Customer Service image via Shutterstock
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