Electric Instant Hot Water Heater Sizing

Rheem tankless electric water heaters make it easy to enjoy instantaneous continuous hot water space saving design and significant energy cost savings.

Electric instant hot water heater sizing.

Tankless water heater sizing calculator. Before we get to how to use the calculator to size a tankless water heater let s talk about the factors that go into understanding what size inline water heater you need. If you want to upgrade your water heater size from 40 or 50 gallons storage water heater or replace it you won t necessarily need a big tankless water heater. Size matters when it comes to your tankless water heater.

Sizing storage and heat pump with tank water heaters. The first hour rating is the number of gallons of hot water the heater can supply per hour starting with a tank full of hot water. How to size a tankless water heater. Looking to purchase a new tankless water heater but having trouble figuring out what size or model you need.

To properly size a storage water heater for your home including a heat pump water heater with a tank use the water heater s first hour rating. The chart below will help you determine the correct electric tankless water heater based on flow rate gpm and temperature rise. In fact it is the most important part of choosing a new unit for your home. The first factor in choosing a tankless water heater is calculating the size of your hot water heater.

Now you need to understand what temperature rise means. Use our handy calculator to determine your needed flow rate and temperature rise then find models that match your needs. For example you might not be able to run more than one shower at a time without someone getting an arctic blast of cold water. Choose the right tankless electric water heater for you.

Gas tankless water heaters are able to produce a larger temperature rise per gpm than electric models. Having a water heater that is too small will result in it not being able to produce enough hot water for your household demand. The right size is a tankless water heater that can heat enough gallons of water to a specific temperature per minute to keep up with the demand. For example an electric tankless heater that is rated at raising the water temperature 55 degrees at 1 5 gpm will supply you with a 120 degree temperature if the incoming water is 65 f or higher.

We already covered gpm. Just follow the three simple steps below to choose the right model and size you need. While traditional tank water heaters are calculated by your family size a tankless water heater is calculated by the quantity and types of fixtures or appliances it will serve.