Water Tank Heaters
Buying Guide
(updated 2018)

AO Smith tank-type gas water heater

Explore gas and electric storage water tank heaters - the most popular type of home water heating products. This is a comprehensive buying guide where the homeowners can get everything they need for the proper tank selection, including; the best models, popular 50-gal models, selecting and sizing tips, removing and installing, cleaning and draining, maintenance and troubleshooting.

If you are looking for the 50-gal gas-powered hot water tank, check out our selection of the top models here, while if electric is your only option, see this review.

Water tank heaters, also called storage, stand-alone and conventional water heaters are very popular in North America.

If you own a condo you are probably renting one of 40 or 50 gallons tank-type unit, like I do from Reliance (my Rheem power vent model was part of the deal when I purchased the condo), and for a monthly charge.

Or you can buy one for the price ranging from several hundred dollars for the economy gas or electric models, up to few thousands for the best models that use the most advanced features, such as condensing gas or electric heat pumps.

If you are not sure should you rent or buy one, read this article to compare and see the pros and cons.

Buying guide

Tank-type water heaters are the most popular type, mainly because of the established market, extensive distributor and service network, reliable operation and good up-front cost. Before going into details, and just to have an idea what other homeowners are searching for, here is the short list of the popular selling models found on Amazon.com:

Type selection

Gas water heaters are probably the best option for homeowners who live in areas where the natural gas is available. Propane or LPG is also a good option, but is more expensive and requires frequent delivery.

Gas models are in general more expensive than electric, but cost less to run and offer more choices with greater flexibility. The best ones are ultra-high efficient or condensing such as Vertex from AO Smith and Polaris from American.

According to Union Gas company (Canada), you can save between $300 and $400 a year (the year 2016 data) compared to electric, but it depends on the fuel rates and compared models.

Electric water heaters are the most affordable option, available to many homeowners, but cost more to operate. For those looking to get more in return for their investment, electric heat pumps are the way to go, as they can deliver more hot water faster and efficient than conventional type. A good choice is Rheem Professional or Voltex from AO Smith. 

Solar water heaters are probably the best choice in southern regions (Florida) where there are more sunny days. The main advantages are the green technology as it uses free and renewable solar energy, and eligibility to governments rebates, stimulation, and help.

The alternatives to the above fuel types are oil-fired burners and wood heaters, but these are less popular.

Capacity

Before buying a water heater, it is important to determine how many gallons of hot water is needed for you and your family, or what is the capacity of the water storage tank, measured in gallons.

The capacity of the water tank-type heaters is usually in the range from 20 to 100 gallons and the most popular sizes are 40, 50, 60 and 80-gallon tanks as they produce enough hot water for the family sizes of 4-6. These are known as the whole-house units, that require no matter what fuel type is used, a floor space and some clearance around and above for other element installation and service.

The best places for the installation are the utility room, laundry, basement or a garage. An attic is also used for the installation but this location has some disadvantages that should be taken into account.

Note: for the same family size and due to the higher recovery rate, you would choose a gas water heater with the lower capacity than if you had to choose an electric unit.

Small size tanks of only a few gallons, like the electrical heater Ariston from Bosch or SHC Mini-Tank from Stiebel Eltron, are mainly for point-of-use applications and are installed near the faucet or shower.

How to select a water tank heater - what you should know

"When is the best time to replace a water heater?" - many will ask.

According to the experts, an average life expectancy of the water tank heaters is 13 years? For tankless is longer, over 20 years.

Most of the today's water heaters have the warranty of 6 years, while the good-quality ones, usually equipped with one or more commercial grade anodes come with the warranty of12 years. The warranty found on tankless models can reach 15 years.

The capacity, First Hour Rate, Recovery Rate and Energy Efficiency are the most important factors when selecting the best water tank heater for home use.

Other features might also be of your interest, and they include the advanced system such as the self-cleaning, diagnostic system, intelligent gas control valve, LED display, hot surface ignition, flue damper, power or direct venting, number of anodes, material quality and other.

Size. Choose the right tank size which will meet the demand at the peak time, but don't select an oversized model, as the energy cost increases. Here is the sizing guide for more info. If you are not sure, ask a plumber or HVAC technician for the advice.

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

Recovery Rate. Recovery rate shows how much of hot water the water heater is capable of producing in a given period of time. When comparing two water heaters, one model has the faster recovery rate if it has more BTU or Watts than the other model.

Keep in mind that greater the demand for hot water is, the higher recovery rate you need.

Efficiency. High-efficiency water heaters are more expensive but pay off faster, also they usually come with the higher quality, efficient energy use, and better warranties. They are also environmentally friendly.

Such models have thicker insulation, more efficient heat exchangers, factory installed heat traps, improved gas burners, and venting.

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

Benefits of the conventional water heaters

  • Simple design
  • Less demanding
  • Cheaper than tankless water heaters
  • High efficient and Energy Star models available
  • Condensing models available
  • Capacity ranges from 2 gallons to over 100 gallons
  • Several sizes available; tall, short, lowboy
  • No minimum water flow required, they can be used for low and high demanding applications
  • If you have a gas-powered water heater, hot water is available even during the power outages
  • Smaller gas requirements
  • Easily adapted for use in solar water heating
  • Great for smaller families

How does a tank-type water heater work?

Conventional water tank heaters have a very simple design which allows easy floor installation, vertically positioned. The main part is the water tank usually made of metal, where hot water is stored and further used for a shower, bath, dishwashing or washing machine.

For better heat retention metal tank is covered with the foam insulation with the thickness from 1 to 3 inches and having different R-value (higher better).

Cold water enters at the bottom of the storage tank, through the dip tube (cold water inlet) and after it is heated by the gas burner or electric heating elements, hot water rises to the upper section of the tank. While the hot water is transferred from the hot water outlet to the open tap, it gets replaced with the cold water.

This process repeats but it depends on the water temperature. If it is lower than the set value on the thermostat, the water heater keeps running; and if it has reached the set value, the heating stops.

There are some models that are equipped with the innovative technology such as the sensors, flow valves, electronics and electrodes providing better performance, greater efficiency and comfort.

The main components found in electric and gas water heaters are explained in this article.

Note: Even with the simple design, tank water heaters have to be installed, maintained and troubleshoot, and the recommendation is to contact the plumbing expert.

Manufacturers

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

  • American
  • AO Smith
  • Bradford White
  • GE or General Electric
  • John Wood
  • Kenmore
  • Marathon
  • Whirlpool
  • Reliance
  • Rheem
  • Richmond
  • State

Tips to save money

High efficiency. If you have an old tank-type water heater, replace it with the energy efficient heater, as the higher efficiency provides more savings in the long run. Look for the condensing models, such as Vertex from AO Smith or Polaris.

Get the model that is solar-friendly.

Install insulation blanket. How to check if 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 money saved; like energy efficient units with thicker foam insulation. If you are considering buying a new unit, choose one with the higher insulation value (R-24 will be the best).

Insulate. There is a lot of heat and energy wasted when waiting for hot water to reach the tap. Insulate all the pipes, especially sections going through the unheated areas and you will reduce the energy loss.

Lower the temperature. You can also save if you lower the temperature on the water heater thermostat by few degrees. If you lower the temperature on the 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. The heaters are usually factory set to the temperatures of 120-125 F.

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