How Does a Tankless Water Heater Work?

Have you ever taken a hot shower and found yourself running out of hot water halfway through? Then a tankless water heater may be for you. Tankless water heaters are becoming increasingly popular in homes. They work differently than traditional tank-style water heaters.

Tankless water heaters are compact, more efficient, and produce an endless stream of hot water. Understanding how tankless water heaters work and the advantages they bring to our daily lives makes them an even more attractive option when selecting a new water heater.

In this blog, we’ll dive into the inner workings of tankless water heaters and go over why they are becoming a sought-after appliance by homeowners.

How Do Tankless Water Heaters Work?

Most tankless water heaters are super efficient and are great for saving energy and space. Instead of continuously heating and storing gallons of hot water in a large tank, tankless models produce hot water on demand when you need it.

Depending on the model you get, the tankless water heater can either be powered by electricity or gas to efficiently heat cold water as soon as it reaches the unit.

If the units are gas tankless water heaters, the water is heated by a gas burner or electrical resistance heating coils. Electric tankless water heaters utilize a heat exchanger and electrical resistance coils to heat and deliver hot water immediately.

For those that like a step-by-step explanation, here’s how a tankless water heater works:

STEP 1 – Hot Water Tap is Turned On

You must turn on the hot water tap to get water into your system. This part is pretty simple, but there are several different ways to do it. If you have a single-knob shower, turn it towards the hot water option.

On the other hand, if you have a dual-knob faucet, all you need to do is locate the knobs, find out which one controls the hot water temperature, and then set it to let that sweet, heated goodness into your system.

STEP 2 – Water Enters the Heater

After turning the hot water on, you don’t have to wait long for warm water to enter your home. Instead of storing it in a large tank like storage tank heaters, the tankless model works differently.

Whenever you turn on the tap, cold water passes through the sensors of the heater, indicating that you’re ready for hot water.

STEP 3 – Water Flow Sensor Detects the Water Flow

The water flow sensor detects the pressure and speed at which the water is moving through the system, playing a pivotal role in accurately calculating how hot the burners need to be. This guarantees an uninterrupted flow of constant hot water without waiting for a tank to fill up again.

STEP 4 – Burners Heat the Water

Once the water flow is detected, the burners kick in and heat the water. The amount of heat is determined by the flow rate and pressure detected in step 3. This not only allows for a highly efficient way to heat water, but it also helps conserve energy.

STEP 5 – Hot Water is Delivered to the Tap

Once the water is heated, it’s delivered directly to the tap without waiting. The tankless water heater works its magic, and you get a never-ending hot water supply, so you can enjoy a nice hot shower or clean dishes without running out of hot water.

Getting Started With A Tankless Water Heater

Generally, most homeowners prefer their water to be in the 100-115 degree range; significantly colder or hotter may cause discomfort and even damage.

Ensure the unit is compatible with the current setup of your plumbing system; these are essential things to consider when buying a tankless water heater.

Map out your plan for installation or hire a professional handyman to take care of it for you. Once you’ve installed your tankless water heater, it’s just a matter of maintenance.

Tankless water heaters deliver a constant hot water flow. They, however require regular flushing to remove any build-up affecting their performance and efficiency over time. Overlooking this step can lead to potential damage. Check in with your water heater often to ensure it’s running at its best.

With the proper maintenance, a tankless water heater will last anywhere from 20 to 30 years. It’s an investment worth making, providing a continuous hot water supply with less energy waste and a longer lifespan than the traditional tank model.

Advantages Of Tankless Heaters

Tankless heating systems are an excellent option for those looking to save on their energy bills. They offer several advantages, including

  1. Instant Hot Water

Tankless water heaters don’t require pre-heating since they heat water as needed – instead of storing it.

Your household can enjoy reliable hot water without waiting for heated water to refill the tank every time you turn on the tap. This eliminates long waits in the shower and prevents costly energy waste that often occurs when using a tank heater.

With no storage requirements or standby losses, tankless hot water systems are both convenient and cost-effective, making them an increasingly popular option for households all over America. You have to think about the cost of tankless water heater installation upfront though.

  1. Longer Lifespan

Tankless heaters are built to last around 25 years, while conventional storage tank water heaters usually max out for around 10 to 15 years—nearly three times the life span.

After installation, you won’t have to worry about another water heater for decades. With regularly scheduled maintenance, tankless water heaters can last even longer and provide consistent hot water throughout their lifetime.

  1. Lower Month-to-Month Cost

Tankless heaters require less energy to heat the same amount of water than traditional water heaters. This results in substantial savings on your utility bill.

In some areas, usage and installment are eligible for government rebates that support transitioning towards a sustainable lifestyle. With their lower month-to-month cost, tankless heaters offer sustainable energy solutions that can bring economic relief and peace of mind.

  1. Space Savings

Homeowners looking to make the most of their space will find a unique advantage in tankless water heaters.

Unlike traditional tank-style heaters, a tankless heater takes up much less room because its lack of a tank means it can be mounted on a wall or installed near the faucet. This gives homeowners more storage and living space than outdated, bulky heaters offer.

Ushering in major space savings for most households, tankless systems also use less energy and provide hot water immediately, making them an incredibly efficient option for energy-conscious customers.

Disadvantages Of Tankless Heaters

Although tankless water heaters offer a wealth of benefits, they also come with drawbacks. Before investing, understand the potential downsides to ensure you make the right decision for your home.

  1. High Upfront Cost

Tankless systems require a sizable initial outlay; their higher sticker price can deter those with budgets or unwilling to commit to the expense. The price of installing a tankless system is significantly higher than that of a conventional tank-style heater, but the long-term savings may outweigh this cost for some.

  1. Power Limitations

Tankless water heaters require more electricity than tank-style models. Consider your home’s current power supply. If your home is not running on an ideal electrical system, you may need to upgrade the wiring and power before installing a tankless. This will add to the upfront cost of the system.

Tankless systems may not be suitable for large households with heavy hot water needs as they generally provide limited hot water at a time.

  1. May Require Additional Equipment

If you’re still considering switching to tankless and already have a traditional water heater, you may need additional equipment to complete the transition.

Unique accessories, such as water filters or recirculation pumps, may be necessary to make your tankless system compatible with the existing plumbing. These extras can add to the installation cost, so factor in all associated expenses when deciding whether or not to switch.

Installation & Maintenance Requirements

Individualized installation and maintenance for your tankless water heater is key to its long-term success.

A certified local plumber is the best option, as they can ensure your product meets all relevant building codes and fuel standards — plus, they can provide you with personalized service that fits your climate, budget, and usage needs.

With some simple attention during installation and standard maintenance afterward, you can help get the most from your tankless water heater for years to come.

Want a Tankless Water Heater Installed in Your Home?

There is a lot to consider when it comes to tankless water heaters. Weighing the pros and cons, calculating energy savings, and understanding how the system works are all critical elements in making the right choice for your home’s hot water needs. If you need a repair on your tankless water heater you can call us for that as well.

To select the correct unit for your specific needs, call Emergency Plumbing Squad today for a comprehensive analysis of your home’s hot water requirements. We’ll have all your questions answered with our expert advice and personalized service so you can have peace of mind when selecting a tankless water heater that will serve all your unique needs.


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