Water Tank Heaters: A Comprehensive Buying Guide

Water tank heaters provide a dependable and cost-effective solution for heating water in your home. Whether you’re upgrading your current system or choosing one for the first time, these heaters offer a range of options to meet your household’s unique needs.

This article will guide you through everything you need to know about hot water storage tanks. You’ll discover how they work, explore their anatomy, and learn how to choose the best model for your home. We’ll also cover proper sizing, installation tips, maintenance, and troubleshooting to help you make a confident decision and keep your heater running smoothly.

What Is a Water Tank Heater?

A tank water heater plays a crucial role in homes consistently delivering hot water for bathing, cooking, cleaning, and space heating.

Often referred to as hot water tanks, stand-alone type, or conventional models, these appliances remain a top choice in North American households due to their reliability and efficiency.

At the core of these devices is an insulated storage tank that uses either electric elements or gas burners to heat water to a preset temperature. Once heated, the water stays in the tank, ready to provide a steady supply of the comfort whenever you need it.

Available in various sizes and capacities, water tank heaters cater to the diverse needs of households and commercial establishments. Their main purpose is to ensure a dependable, convenient, and efficient source of hot water, making everyday tasks more comfortable and hygienic.

How Does a Water Tank Heater Work and Its Main Components

Conventional water tank heaters feature a straightforward and effective design that simplifies installation, typically as a vertical unit placed on the floor.

At the heart of the system is a metal storage tank, which holds hot water for everyday activities like showering, dishwashing, and laundry. To minimize heat loss, the tank is surrounded by foam insulation (1 to 3 inches thick), with varying R-values—higher values indicate better insulation.

Cold water enters the tank through a dip tube at the bottom. It is then heated by either a gas burner or electric heating elements. As the water heats, it rises to the top of the tank, ready to flow out through the hot water outlet when you turn on a tap. Simultaneously, cold water replaces the used hot water, ensuring a continuous supply.

This heating cycle continues until the water reaches the temperature set on the thermostat. If the water cools, the heater automatically reheats it.

Some advanced models feature technology like sensors, flow valves, electronics, and electrodes to boost efficiency, performance, and comfort.

Key Safety Features in Water Tank Heaters

Water tank heaters are equipped with several safety features to ensure safe operation:

• Anode Rods and Glass Lining: These components protect the tank against corrosion, prolonging the heater’s lifespan.
• Drain Valve: This feature allows for regular draining and flushing to maintain the system’s efficiency and prevent sediment buildup.
• TPR Valve: The Temperature and Pressure Relief valve ensures that the water heater doesn’t exceed safe pressure or temperature limits, preventing potential hazards.

Although these heaters are reliable and easy to use, they still require proper installation, regular maintenance, and occasional troubleshooting. For any issues, it’s always best to consult a plumbing expert.

Explore more about the components and functions of electric and gas models in this article.

Difference Between Tankless and Tank Water Heaters

The key difference between tankless and tank water heaters is how they provide hot water.

Tank heaters store hot water in a large tank and continuously heat it, making them ideal for households with moderate hot water needs.

In contrast, tankless models heat water on demand, providing endless supply without the need for a storage tank. Tankless models are more energy-efficient since they only heat water as needed, but they often have higher upfront costs and may struggle with simultaneous high-demand use.

Here is a detailed comparison of tank vs. tankless to help you choose the best option.

Types of Water Tank Heaters

Homeowners have the option to choose from the three most popular types of hot water tanks: gas, electric, and solar-powered. Each type has its own advantages and disadvantages. The choice depends on factors such as fuel availability, energy efficiency, cost, and environmental impact.

Gas-Powered Models

Gas water heaters utilize natural gas or propane to heat water. They have a gas burner at the bottom of the tank with a chimney running up through the center of the tank. It is used to vent exhaust gases outside.

How they work: When the water temperature drops below a preset level, the gas burner automatically ignites, transferring heat to the water in the tank. This process quickly raises the water temperature. Meanwhile, any exhaust gases created during combustion are vented outdoors through a flue, ensuring safe operation.

Pros and cons: Gas units typically have lower operating costs because gas is cheaper than electricity in many areas. They also heat water faster than electric models. However, they require proper venting to the outdoors, have a higher initial cost, and pose a slight risk of gas leaks or carbon monoxide exposure if not properly maintained.

According to Eastward energy, homeowners can save between over $500 annually compared to electric models. Actual savings, however, depend on fuel rates and the specific models being compared.

Electric Models

Electric water heaters use resistance heating elements submerged in the tank to heat water. They are a popular choice due to their simplicity and the widespread availability of electricity.

How they work: When the thermostat detects that the water temperature has dropped, it activates one or more electric heating elements. These elements heat the surrounding water until it reaches the desired temperature. The hot water remains in the tank, ready for use.

Pros and cons: Electric models are easy to install, require no venting, and typically cost less upfront than gas models. However, they are usually more expensive to operate due to higher electricity costs and won’t work during power outages.

Solar Water Heaters

Solar heaters harness the power of the sun to heat water, offering an eco-friendly alternative to traditional methods. They use solar collectors, typically mounted on the roof, to capture and convert sunlight into heat.

How they work: The solar collectors absorb sunlight and transfer the heat to a fluid, which circulates through the system. This fluid heats the water stored in a tank. On cloudy days, a backup system (either electric or gas) ensures you still have access to hot water.

Pros and cons: Solar heating devices can significantly lower energy bills by relying on free, renewable solar energy. They also reduce your carbon footprint. However, installation can be expensive, and efficiency depends on weather conditions, requiring a backup system for consistent performance.

Hybrids

Heat pumps, also known as hybrid water heaters, use electricity not to generate heat directly but to move it from one place to another, making them more energy-efficient than traditional electric heaters.

How they work: A heat pump, located on top of the tank, extracts heat from the air or ground and transfers it to the water. This process uses much less energy than traditional heating methods, reducing energy consumption by up to 60%.

Pros and cons: Hybrids provide significant energy savings and lower operating costs compared to conventional electric or gas models. However, they have a higher upfront cost, need more space for proper airflow, and their efficiency can decrease in colder environments.

Sizing Tips: Choosing the Right Capacity

Determine Water Tank Capacity

Choosing the right water heater size is crucial to ensure you have enough hot water to meet your household’s needs.

Start by calculating how many gallons of hot water your household uses during peak demand. This occurs when multiple faucets or appliances operate simultaneously. Add the flow rates (in gallons per minute) of all hot water fixtures you use at the same time. Multiply the total by the duration of use.

Next, consider your household size, the number of bathrooms, and your typical hot water usage. As a general rule, allocate 10–15 gallons of tank capacity per person. Larger tanks may be necessary if you use large bathtubs or Jacuzzis.

Tank heaters typically range in size from 20 to 100 gallons. Popular options include 40-, 50-, 60-, and 80-gallon tanks. These options typically meet the needs of families of 4–6 people.

Consider the First Hour Rating

You should also evaluate the heater’s First Hour Rating (FHR) and recovery rating. The FHR measures how much hot water the unit produces in the first hour, while the recovery rating indicates how quickly the heater can reheat a full tank of water. Select a unit with an FHR that matches your peak demand, and prioritize a higher recovery rating to ensure continuous hot water during busy times.

If space is limited or energy efficiency is a top priority, consider upgrading to a tankless water heater.

For smaller-scale needs, opt for compact models designed for point-of-use applications, such as the Bosch Ariston or Stiebel Eltron SHC Mini-Tank. These units are installed near faucets or showers and offer an efficient solution for localized hot water needs.

How to Select a Water Tank Heater

Life Expectancy and Warranty

Many homeowners often wonder, “When is the best time to replace a water heater?”

Experts estimate the average lifespan of tank water heaters to be around 13 years, while tankless models can last over 20 years. Most of them include a 6-year warranty, though premium models with commercial-grade anodes may offer a 12-year warranty. Tankless units often come with warranties of up to 15 years, making them a durable and reliable option.

However, factors like water quality, regular maintenance, and usage patterns significantly affect a heater’s lifespan. As a rule of thumb, consider replacing a unit that is over 10 years old, even if it seems to function properly. This proactive approach helps prevent unexpected failures or leaks that could damage your home. Additionally, if you notice rust, corrosion, or leaks, consult a professional to assess whether the unit requires replacement.

Choosing the Right Size for a Sufficient Hot Water Supply

Choosing the right tank size is essential to meet your household’s hot water demand during peak times.

An oversized water heater can lead to higher energy bills, as it heats more water than you need. This unnecessary heating increases energy waste and costs. Additionally, a larger unit may take up more space, which could pose a problem in homes with limited room.

On the other hand, an undersized water heater can leave you with insufficient hot water during busy periods, such as when multiple appliances or faucets are in use. This not only causes inconvenience but also overworks the unit, reducing its lifespan and increasing maintenance costs.

For more information, refer to a sizing guide or talk to a plumber or HVAC technician for advice.

First Hour Rate

The first-hour rate (FHR) measures how much hot water a water heater can produce in one hour, combining tank capacity and recovery rate. This rating is especially important during peak usage times to ensure your household has enough hot water when it’s needed most.

Recovery Rate

The recovery rate of a water heater indicates how much hot water it can produce within a specific time frame. A model with a higher number of BTU or Watts will typically have a faster recovery rate than a lower-rated one.

When choosing a water heater, it’s important to consider your household’s demand for hot water. The greater the demand, the higher the required recovery rate to ensure that you have enough hot water when you need it.

Efficiency

High-efficiency models may come with a higher upfront cost, but they pay off more quickly in terms of energy savings. In addition, they typically offer better quality, efficiency, and warranties, while also being more environmentally friendly.

These models often feature 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 the uniform energy factor (UEF). A higher UEF means better efficiency, helping you save money on energy bills while reducing environmental impact.

Available Features

The capacity, first-hour rate, recovery rate, and energy efficiency are the most important factors to consider when selecting the best water tank heater for home use.

However, you may also want to consider available features. These include advanced systems such as self-cleaning and diagnostic systems, as well as intelligent gas control valves.

Other features to consider include LED displays, hot surface ignition, and flue dampers. Also, power or direct venting, the number of anodes, and the quality of materials.

How Much Does a Water Tank Heater Cost?

The Home Depot provides useful information on the cost of water heaters.

For a 50-gallon gas water heater, the price range is between $500 for basic models with a 6-year warranty and $1400 for advanced models with a 12-year warranty. These models feature power venting, produce ultra-low NOx emissions, and have high-quality components.

In contrast, electric water heaters are generally cheaper, with standard models ranging from $400 to $900. This depends on the warranty and element quality. Hybrid electric models can be more expensive, costing up to $2000.

Popular Manufacturers: Why Brand Choice Matters

Choosing the best water heater brand is crucial for ensuring high performance, reliability, and longevity. Trusted brands not only offer quality materials but also enhance energy efficiency and provide better customer support, which helps minimize the risk of costly repairs. Additionally, these brands often come with robust warranties, offering peace of mind to homeowners. To assist in your decision-making process, the list of popular brands is included below.

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

Benefits of Water Tank Heaters

• Proven and Reliable Design. Traditional tank water heaters have been used for decades, offering a reliable and effective solution.
• Low Maintenance. Tank-type models require less maintenance than tankless units. They don’t need special installation, ventilation, or regular flushing and descaling.
• Cost-Effective. Traditional tank heaters are typically more affordable than tankless units, and their simpler installation process can reduce installation costs.
• Energy-Efficient Options Available. While tank water heaters are generally less efficient than tankless models, many high-efficiency options, like Energy Star-certified models, are available.
• Condensing Models. Some models use a condensing system to capture and reuse heat that would otherwise be wasted, enhancing efficiency.
• Variety of Sizes. Tank water heaters come in a wide range of sizes, from small units for tiny homes to large units for big families.
• Multiple Styles and Sizes. Tank heaters come in various shapes and sizes to fit different spaces and meet diverse needs.
• No Minimum Flow Required. Unlike tankless models, tank types don’t require a minimum water flow rate, making them suitable for various applications.
• Hot Water During Power Outages (Gas Models). Gas-powered tank heaters continue to provide hot water even during power outages, which is ideal in areas with frequent outages or natural disasters.
• Lower Gas Consumption. Traditional heaters require less gas than tankless models, offering more cost-effective operation, particularly in areas with high gas prices.
• Easily Integrated with Solar Systems. Tank water heaters can be easily adapted to work with solar heating systems, helping to reduce energy costs.
• Ideal for Smaller Families. Tank water heaters are often the best choice for smaller families or households with lower hot water demands. They offer a more affordable and practical solution than tankless models.

Drawbacks

• Increased utility bills since a heater is heating water even if there is no demand.
• Lower efficiency
• Larger footprint
• Limited hot water capacity
• Shorter warranty
• Short lifetime
• Requires regular cleaning due to the sediment buildup issue (in hard water areas).

Tips to Save Money

Get a High Efficiency Model

If you have an old tank-type water heater, consider replacing it with a more energy-efficient model. This upgrade can help you save on utility bills over time.

Consider looking for condensing models like the Vertex from AO Smith or Polaris, which have higher efficiency. Also, consider getting a model that is solar-friendly to further reduce energy costs.

Install an Insulation Blanket

Want to check if your water storage tank heater is wasting energy?

Try this simple test: place your hand on the outside surface of the tank. If it feels warm, your unit likely needs better insulation.

Adding an insulation blanket or “jacket” reduces standby heat loss and boosts savings. This is similar to energy-efficient units with thicker foam insulation.

If you’re in the market for a new unit, look for one with a higher insulation value. R-24 is considered the best insulation value, and will help ensure that your water heater operates as efficiently as possible.

Insulate Pipes

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

One way to save energy with your water heater is to lower the thermostat temperature by a few degrees.

For every one-degree reduction, you can save one percent of energy consumption over eight hours. The recommended temperature range is between 120 and 140 degrees Fahrenheit, although some factory settings may be lower, between 120 and 125 F.

Keep in mind that lowering the temperature too much may affect hot water availability and potentially cause bacterial growth. It’s best to consult with a professional plumber to determine the optimal temperature setting for your water usage needs.

Common Water Tank Heater Problems

Tank water heaters can encounter various issues that prevent them from working effectively. For gas models, you may experience problems like a failed pilot light or thermostat. Electric models might have malfunctioning heating elements or thermostats. Additionally, both types can face issues like leaks, strange noises, rotten egg smells, water that is too hot or not hot enough, and discolored water. It is worth noting that these problems can often stem from improper installation or lack of routine maintenance.

To prevent such issues, proper installation and regular maintenance are essential. A well-installed water heater performs more efficiently, reducing the likelihood of unexpected problems. Routine maintenance ensures that the system continues to function optimally and can help identify potential issues before they worsen. While some problems are hard to tackle, others can be fixed with DIY repairs. We have provided a guide on troubleshooting water heaters, but be cautious. If you’re unsure about making repairs or if the issue persists, contacting a professional for help is always a smart choice.

Are Water Tank Heaters Worth the Investment?

Water tank heaters provide a reliable, traditional solution for households with moderate hot water needs, offering a simpler alternative to tankless systems.

Although they were once considered less efficient, recent advancements have led to high-efficiency models exceeding 90%, such as the Polaris and AO Smith Vertex for gas, and Rheem and AO Smith electric hybrids.

These innovations enhance energy savings and performance, making them more appealing.

When evaluating options, consider energy efficiency, capacity, and initial cost to determine if a tank or tankless system best suits your needs.

By choosing the right heater, you can enjoy both reliability and modern efficiency upgrades.

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