A tankless heater heats water as it passes through the heater. It does not store hot water like a traditional tank water heater. The tankless heater turns on when it senses flow, heats the water and hot water flow out the outlet. When the flow of the water stops, a flow switch detects this and the tankless heater turns off. Tankless heaters only use electricity when they are providing hot water. A tank heater is continually using electricity by keeping the water hot waiting for a faucet to be turned on.
There are tankless heaters designed for the whole house, just sinks or for use in industrial plants.
Industrial use tankless heaters are sometimes called inline heaters or circulation heaters. They can be made quite large to heat large volumes of water, gases or oils. In home or commercial use tankless heaters are smaller and require less power to operate.
Tankless heaters do have a limitation. The limitation is the amount of flow that the heater can heat. For example, our 17 kilowatt (kw) heater (AE115) designed to operate in a home in the southern USA, can heat a flow rate of 2.5 gpm of water, 45 degrees F. Meaning that the water temperature will be raised 45 degrees from the inlet temperature to the outlet temperature. At a higher flow rate the degree change will be less, and at lower flow rates the change will be greater. The 27 kw heater (AE125) will raise the the water 45 degrees at a 4.0 gpm flow rate and 65 at the 2.5 gpm. 2.5 gpm is a standard shower flow rate.
Both of the AE tankless heaters heaters require larger breakers in the electrical panel than a tank heater. The AE115 requires 2 x 40 amp two pole breakers and the AE 125 requires 3 x 40 amp breakers. Both heaters operate on 220-240 volts AC. Also the wire gauge needs to be 8 to carry the larger amperage load.
The tankless heater will save on electrical usage since it is only heating water when it is required. A tank heater is on for many hours a day and also on when no one is home, thus wasting electricity. A tankless heater can use up to 1/2 the amount of power to heat your water. Another advantage is the tankless heater takes up very little space and can be located just about anywhere in the home.
Sords Electric has electric tankless heaters for sinks, AE7.2, AE9.5 and AE12 Power Stream heaters. These heaters draw 30, 40 and 50 amps respectively. We also carry the AE115 and AE125 for whole house use. The amperages are 80 and 120. Only one shower can be run at a time but back to back showers can be run all day long.
