Gas Water Heater

The standard "tank type" water heater is found in most homes and with just a little maintenance, provides years of trouble free operation. Unlike tankless water heaters which have no storage stank, the tank type water heater heats cold water and stores the hot water until it is needed.

The gas water heater works by a law of physics called convection which loosely paraphrased, states that heat rises. Heat rising and convection is a simple rule that you live with everyday and a hot water tank is no exception. Cold water is supplied to the tank and injected at the bottom of the tank through a dip tube. The denser cold water stays there and is heated by the gas burner. As the water heats up, it naturally rises and is drawn off by the hot water discharge pipe.

Gas fired heaters have maximum recovery efficiencies of only about 86% (the remaining heat is lost with the flue gasses). Overall energy factors can be as low as  50% for gas systems. Natural gas and propane tank water heaters with energy factors of 62% or greater,  are considered high-efficiency units. Energy Star-qualified natural gas and propane tank water heaters have energy factors of 67% or higher; however, the Energy Star program does include electric heat pump units with energy factors of 200% or higher. Tankless gas water heaters must have an energy factor of 82% or higher for Energy Star qualification.