Water Tank Heaters

Storage tank sizing guide, cleaning, removing and flushing

Water tank heaters, also called storage, stand alone and conventional water heaters are very popular in North America. If you own a house or condo, you are probably renting one of the 40 or 50 gallons tank-type heaters, like I do from Reliance (it came with a condo), and for a monthly charge. Or you can buy one.

Guide to water tank heaters

This article is not about which heater is the best, but it focuses on conventional, water tank heaters, how they work, types, benefits, articles about cleaning, draining and flushing, sizing and much more (see popular articles below).

If you have the ability to use natural gas, don't think twice. If water tank heaters are what you are looking for, gas heaters are probably the best option for your house.

And with the rising awareness about green technology and renewable energy, solar heating with solar tanks is also a good choice. But, unfortunately, there are so many restrictions there.

Also, you can find heaters that are using oil fired burners, electricity and propane, for water heating.

water tank heatersIt doesn't matter which fuel type you will choose, cylindrical tanks, where hot water is continuously kept hot inside the tank, needs a special technical room, closet or garage.

These tank type heaters are usually in a range from 20 to 100 gallons and the most popular are 40, 50, 60 and 80 gallon tanks as they produce enough hot water for the standard family size of 4 to 6 members. Small size tanks of only few gallons, like electrical heater Ariston from Bosch are mainly for point of use applications. Water tank heaters that we will cover here are whole-house units.

When replacing a tank-type heater use the name-plate found on the heater to collect necessary information, including the capacity, insulation R-value, pressure rating of the tank, wattage and voltage of the electric heating element or BTU for gas unit.

Yellow tag is the energy guide label that shows the yearly costs of your heater.

How does a hot water tank work?

Water tank heaters are very simply designed. Their main cylindrical part is a storage tank, where hot water is stored and drawn for the shower, bath, dishwashing or washing machine. In North America they are usually standing on the floor in vertical position.

Cold water enters the bottom of the storage tank through the dip tube and soon after it is heated by the gas burner or electric heating elements, hot water rises to the top of the tank. Whenever you are using hot water, it is replaced with cold at the bottom through the dip tube.

Standard tank water heaters are designed simple so troubleshooting is easy. Access panel at the front of the tank heater is conveniently positioned so replacing any faulty part is worry-free.

Types of water tank heaters based on the fuel source

  • Oil fired heaters

emergency plumber


Here is the list of the popular brands/manufacturers of the HVAC equipment, including water tank heaters, in North America:

  • Whirlpool

  • Maytag

  • Reliance

Tips to save money

  • If you have a traditional tank-type water heater, by replacing it with the energy efficient heater you will definitely save on the long run.

  • Or if it is feasible, consider solar storage water heaters.

  • How to check is your tank water heater wasting energy? Put your hand on the outside surface of the tank and if it feels warm your unit needs better insulation. If you install the insulation blanket or jacket, standby heat loss will be reduced and you will save some money; like energy efficient units with thicker foam insulation. If you are considering buying a new unit, choose one with the higher R, insulation value (24 will be the best).

  • There is a lot of heat and energy wasted when waiting for hot water to reach the tap. Insulate all the pipes and you will reduce the energy loss.

  • If you lower the temperature on water heater thermostat by few degrees you are on the right way to save. Lower the temperature on your thermostat by one degree for an eight-hour period and you will reduce the energy consumption by one percent. The recommended temperature is between 120-140 degrees F.

  • To save money on your bill, our suggestion is to buy high efficiency water tank heater as they can perform as much as 40 percent better than conventional models.

Note: Do you know that the average life expectancy of the heater is 13 years?

How to select hot water tanks - what you should know

Choose the right tank size, but don't select an oversized heater, as the energy cost increases. If you are not sure, ask plumber or HVAC technician for the advice.

Hot water delivery capability or First Hour delivery is a combination of a tank capacity and its recovery rate or how much hot water it can produce in one hour.

High efficiency water heaters are more expensive but it pays off and it usually comes with higher quality, efficient energy use and better warranties.

The efficiency of gas, propane, and oil-fired water heaters is measured by an energy factor (EF). Higher - better.

Electric water heater's efficiency is measured by standby loss or rating watts loss. Low-better.

For aditional help here are the buying guides from Home Depot and consumerreports.org.

Related Articles

(All pictures are courtesy of AO Smith)

tank type heaters form
water heaters