Dual Element Water Heater Vs Single Element

Many modern homes come with dual element water heaters.

Dual element water heater vs single element.

The thermostat used in single element electric water heater is different than the double dual element water heater. The upper element heats the upper portion of. With two element designs one element heats the water at the top of the tank while the second element heats the water within the bottom of the tank. Each type has its advantages but single element water heaters are usually only models of 30 gallons and less.

The dual element is the more efficient of the two water heating systems. Low density water heater elements use less watts of energy per square inch so they are made longer in length to make up the watts rating of the element. Dual element units are easily recognizable by the two raised panels in the front for access to replace the elements. It heats water quicker than a single element unit as water is moved from one end of the tank to the other whereas a single element system heats from the bottom up only.

One major reason for the popularity of dual element water heater systems stems from the fact that they heat up water faster and more efficiently. A dual element water heater uses two heating elements controlled by two separate thermostats. Whereas gas heaters heat water with a burner that produces a flame electric heaters instead use electricity to heat an element. Single element water heaters only have one source of heat located near the bottom of the tank so it can take a while for the water at the top of the tank to heat up.

A 4500 watt high density element generally has 30 square inches of surface area and a 4500 watt low density element generally has 60 square inches of surface area. Dual element water heaters are recognizable by the two raised access panels one over the other as in the photo above at the side of the water heater for each element whereas the single element water heaters only have one. In other words there are two screws on the right side in single element thermostat switch which is fixed to the heating element while a dual element thermostat has 3 screws on the right side.