Unlike traditional water heaters, which store hot water in tanks and continuously heat it, tankless water heaters heat water on demand. When you turn on a hot water tap, the tankless water heater heats the water as it flows through the unit, providing a continuous supply of hot water. 

If you’re considering upgrading your water heater, you may be wondering whether a tankless water heater can handle two showers at once. The answer is not a simple yes or no, because it depends on several factors. Keep reading to learn what determines whether a tankless water heater can provide enough hot water when demand is high, such as when two family members are taking showers at the same time.

Size of the Tankless Water Heater

Whether you prefer a gas or propane tankless water heater, you can get a virtually limitless supply of hot water if you choose a model that’s the right size for your household’s needs. Tankless water heaters are sized based on their flow rate, which is measured in gallons per minute (GPM). To determine the right size for your household, you’ll need to consider the number of hot water fixtures you use at the same time. 

For example, if you have two showers that are used simultaneously and each showerhead has a flow rate of 2.5 GPM, you’ll need a tankless water heater with a minimum flow rate of 5 GPM. If you have additional hot water fixtures, such as a dishwasher or washing machine, you’ll need to factor those in as well. If you install a tankless water heater that’s too small for your household’s needs, you may run out of hot water during peak usage times. 

Water Temperature Rise

The second factor to consider is the water temperature rise. This refers to the difference between the temperature of the incoming cold water and the desired hot water temperature. For example, if the incoming water is 60°F and you want the hot water to be 120°F, the temperature rise is 60°F.

The larger the temperature rises, the more work the tankless water heater has to do to heat the water to the desired temperature. If the temperature rise is too high, the tankless water heater may not be able to keep up with the demand for hot water. In some cases, you may need to adjust the desired water temperature to ensure you have enough hot water for simultaneous usage, but this isn’t likely to be an issue in a warmer climate such as San Diego, where the temperature of the incoming water is generally tepid.

Water Pressure

The fourth factor to consider is the water pressure. Tankless water heaters require a minimum amount of water pressure to function properly. If the water pressure is too low, the tankless water heater may not be able to provide enough hot water for simultaneous use. If you’re experiencing low water pressure, you may need to have a water pressure booster installed to ensure your tankless water heater can operate correctly.

The right tankless water heater can definitely take care of all your family’s hot water needs, including taking multiple showers at once. If you’re considering upgrading to a tankless water heater, it’s essential to work with experienced professionals. Call on the experts from Arnett’s Water Systems, the tankless hot water heater specialists San Diego homeowners rely on for exceptional service. Give us a call today at (619) 223-1209 to find out how we can help you choose the tankless water heater that’s right for your family’s needs.