What is a water heater?

This is a device for producing hot water for household purposes. Some common types are an oil or gas fired, or electric resistance water heater combined with a storage tank.

Why shop?

Since heating water contributes to maximum electricity consumption, it is always better to analyze the energy efficiency and size, while installing a new water heater.

Tank Vs Tankless Water Heater

Regarding energy efficiency, tank water heater consumes more electricity to operate than the tankless type. As hot water is heated and stored constantly in the tank water heater, energy consumption is high. In tank water heater, cold water is supplied in the tank as soon as hot water is drawn off. Thus, the reservoir is always full with hot water, even if it is not required. This way energy is wasted in a tank water heater, which is called standby heat loss.

As the amount of hot water availability in a tank water heater depends on the size of the reservoir, there are chances of insufficient or excess hot water. Whereas in tankless water heater, hot water can be withdrawn constantly. Since hot water is supplied on the demand basis, tankless type is also referred to as demand or instant water heater.

While purchasing a tank water heater, the size of the tank is the major criteria for selection. A smaller size tank water heater may not be sufficient to provide the required hot water, while an extra large size may result in energy wastage. Hence, depending upon the hot water requirement and family size, correct size tank water should be installed. Since there is no storage tank in tankless water heater, size is not an issue while selecting the tankless type.

One word of advice for tank water heater is to insulate the tank properly so as to reduce standby heat loss and chances of corrosion and rust. Otherwise continuous water storage lead to corrosion of the tank and lowers the lifespan of water heater. In tankless water heater, sediment filter in the water inlet pipe and regular flushing of the heat exchanger are necessary to prevent cracking.

http://www.buzzle.com/articles/tank-vs-tankless-water-heater.html

 Overview:

 Tankless hot water heaters are more effienct because they

• use less electricity
• only heat water as it is being used
• one size fits all tank
• don't need to worry about tank corrosion which lowers the lifespan of water heater