Electric water heater - A buyer's guide

Posted on 24 November 2019

Water Services,

How to buy the right electric water heater for your needs: There are four fundamental factors a buyer needs to consider when purchasing a new electric water heater:

  •      The cost of the heater
  •       The cost of fuel
  • ·     Size 
  •       Energy efficiency

When it comes to choosing which electric water heater makes most financial sense for your business, it is important to consider two expenses together: the purchasing cost of the unit, and the cost to run it. A lower-priced unit could turn out to be costlier in the long run, as it is not equipped with energy-efficient technology. The good news is there are many types of electric water heaters that optimize cost and energy efficiency, and are specifically suited for the needs of different household, commercial and industrial projects.

The type of fuel available to an area/ project also determines the kind of water heater a building contractor will purchase. This is an important consideration that project designers and construction engineers need to keep in mind, as the cost and energy efficiency between a home- or a business-development project greatly varies depending on the energy source used to power water heaters. While there are a variety of energy sources that can power water heaters – gas and thermal, included – for this article we will only focus on electricity-run options. 


For any business to commit to a certain kind of water heater for a project, you would need to know the advantages and disadvantages, as well as the variety of choices available in the market. Informed with this information, a business project will thereafter be able to weigh out, not only the initial costs of purchasing such a unit, but also estimate and evaluate the running cost of a water heater based on a business’s long term needs.

For example, a residential project would have different water-heating needs than an office space. Equally, a larger water-heating device would be needed to heat the needs of sports facilities. Moreover, given the climatic conditions of the region, as well as the range of temperatures spikes and dips, a professional water heater supplier, with regional work experience, would be in the best position to advise on water heater models and energy-efficiency strengths and weaknesses.

The following types of electric water heater designs are common in the market:

Conventional-storage water heaters

Storage water heaters are most popular for home usage, because they store a large amount of water at once, usually between 20 and 80 gallons, heating as the consumer needs, for various household purposes. It is useful to understand how they operate: When a user turns on their hot-water tap, the tank releases heated water from the chamber. At the same time, cold water refills the bottom of the tank, ensuring that the chamber is always full, and water is available for heating as and when required. Given the size and capacity of this water heater, it is most popular across residential construction projects. This kind of conventional water heater services small household tasks that require heating, for example in residential bathrooms, kitchens and laundry areas.

Storage-based water heaters, however, are not the most efficient option because they lose standby energy, and are therefore costlier for the end consumer in the long run. 

Tankless water heaters

Tankless water heaters are a good option to consider as an alternative to conventional-storage water heaters. As they work ‘on demand,’ they are also referred to as ‘demand type’ or instantaneous water heaters. Additionally, as tankless water heaters are not attached to a storage unit, standby-energy losses are not incurred. Instead, the way they work is this: An electrical heating unit heats cold water as it passes through the pipe and into the tap. The major advantage to this system is that a user never finds themselves waiting for a storage tank to fill. The water heats immediately as it passes through the unit, providing hot water instantly.


The drawbacks to the tankless option, however, is that they are not endless suppliers of energy. If multiple appliances are running simultaneously, for example a dishwasher and a washing machine, they may tap out the energy of a tankless water heater as it will not be able to keep pace with the large amount of heated water required.   A solution to this, that building contractors employ across projects, is to supply different heavy water-use appliances with independent tankless water heaters. While the initial purchase of this type of water-heating unit can be more expensive, tankless water heaters are more energy efficient, last longer, with up to a 50% greater lifespan, and have easily replaceable parts, for long-term maintenance. 

Heat pump. The best way to understand heat pumps is to think of them as refrigerators in reverse. They are devices which use electricity to take heat from the air and transfer it into the water to heat it. As heat pumps use electricity to capture heat and move it from one place to another, they are dependent on the surrounding environment being warm enough, to work effectively. In order for them to function optimally, they need to be installed in places where temperatures don’t fall below 4 degrees Centigrade (40°F) or rise beyond 32 degrees Centigrade (90°F). Large water areas like swimming pools are often heated by heat pumps.  As the pump circulates the swimming pool's water, it continually passes through a filter and a heat pump heater, which instantaneously heats and flushes it back into the swimming pool.

The advantages of electric-heat pumps are that they heat via geothermal conduction and work equally well to heat or cool water.

Tankless coil heaters and indirect water heaters. These systems piggyback off a home or facility’s space-heating system. They do not use tanks, and instead, when a hot-water tap is turned on, the water passes through a heating coil connected to the central furnace in a home or facility. These types of water heaters are great for large homes and huge building facilities in colder climates, where space-heating systems are regularly operational.



Electric water heaters come with a variety of features, with respect to size and installation options. Residential water heaters come in convenient wall-hanging styles, or standalone, upright styles that can hold from 20 to 80 gallons of water. This allows contractors to make choices based on the number of bedrooms/average number residents in the residence, where cost-per-usage is determined on household consumption. Industrial water heaters, in contrast, can have capacities as high as 5000 gallons to safely power entire facilities and their multiple operations.

Here are some interesting features of different types of
electric water heaters to consider to help businesses make the right choice according to their project needs.

Storage water heaters have temperature and pressure release valves in-built for their safe operation. These valves release if either measurement increases beyond their specified levels.

The heat coils in an indirect, electric water heater, are made of copper, and touch a connected space-heating source. As copper is one of the best conductors of heat, such coils significantly increase the temperature of water. Another valve connected to an unheated-water source reduces the water temperature to a comfortable, useable level.

Space is an important consideration when purchasing a heat-pump electrical water heater. While they use significantly less energy than other heaters, because they take heat from the air, they also produce condensation, which requires proper attached drainage facilities to discard of the waste.

Tankless, electric water heaters are one of the most convenient options for a home, because of how little space they take up. They can even be installed discreetly inside closets to remain completely out of sight, thereby taking up little to no space, that can easily be camouflaged through storage or design aesthetic. 


Installing a water heater in a home, commercial or industrial project is an expensive undertaking for a construction company. Therefore, it is important to make an informed decision about the different kinds of electric water heaters, and the needs they will be servicing. Equally important for project developers is to use a reliable brand that has built a reputation for long-lasting usage and energy efficiency.  An experience supplier of water heaters will be able to help project developers in making the right choice, depending on available energy sources, estimated daily water usage, space for installation, and the type of customization available, depending on the end user.

This is why it is really important for construction developers to weigh short-term costs against long-term benefits. Buying a higher-priced heater can mean optimizing payoffs in the long run with a more energy-efficient system and easy-to-replace parts, for longer upkeep and shelf-life. This saves a project developer unnecessary construction expenses, as well as builds on a company’s reputation and brand value for excellence in construction.

Construction managers are advised not only to go to a reputable, well informed supplier for the best water heating brands, but also carefully consider the expertise of the company undertaking installation. Specialized tradesman, who are knowledgeable about home, commercial and industrial sites, electrical wiring, and plumbing should be hired to install water heaters. Sourcing from, and hiring a professional company with comprehensive expertise at installation, will ensure that a project runs smoothly without hiccups.

When looking for a water-heating solution, take time to research the suppliers in the market. For more information on water-heating options to suit your business needs, click here