A tankless water heater in Harlingen can be operated through gas or electricity. The electric tankless water heater is considered to be more affordable than gas. Its installation is less complicated as compared to the gas model because of the absence of vents. They are very low in maintenance and boast a high energy rating. Gas tankless water heaters come in different sizes and models that you can choose from. They are available for both residential and commercial grades. This kind of Harlingen tankless water heater costs more than the electric one because of the utilization of fuel.