Myth: Tankless Hot Water Is Instantly Hot
“Tankless water heaters provide instant hot water in the home.”
Myth #4: Gas Tankless water heaters are instant hot water heaters.
Tankless water heaters are often advertised as being able to provide instant hot water. While it is partially true, there is a bit more to this claim.
As we have mentioned previously in this blog, storage hot water tanks provide instant hot water because they store water and keep it heated to a desired temperature so it is constantly ready for use. This is technically inefficient because standing hot water eventually cools and either your electric water heater elements will turn on to keep the water heated, or your gas water heater pilot light will fire up to keep the temperature constant, even if the hot water isn’t going to be used.
With a gas tankless water heater, water is heated only when you turn on a faucet or use a fixture that needs hot water, like a dishwasher or washing machine. Because it takes a short period of time for the water to heat up, there is a small lag of typically 30-60 seconds to receive hot water. (This isn’t usually advertised.)
This lag can be reduced or eliminated by having a re-circulation pump (a.k.a. hot water circulation pump) or re-circulation line installed to keep water moving to experience instant hot water. You can also have an instant hot water tap installed at your kitchen sink for fast hot water.