Just like it’s possible to replace a tankless water heater with a tank unit, it’s possible to easily get rid of the aged tank water heater and have a brand new and advanced tankless unit installed. However, you must first address the two main requirements for replacing tank water heaters with tankless units. If installing gas-electric tankless water heaters, you have to invest in special pipe vents and bigger gas supply lines because your new heating unit will need them to efficiently supply water to the heater and other appliances connected to the gas pipe. If you invest in an electric unit, you will have to invest in a bigger gauge wire and breakers that aren’t common with standard tank-type water heaters.