Instant hot water heater, or on-demand water heater

Instant Hot Water Heater Questions Answered!

Is an instant hot water heater right for you? These models aren’t a brand-new concept, but they’ve certainly grown more popular recently.

An instant water heater — also called a tankless or on-demand water heater — is a replacement for the conventional storage water heater. For many homes, they’re a great option due to their energy efficiency and low operating costs. They also have some disadvantages, however.

Let’s look at the difference between an instant and storage water heater, pros and cons of instant water heaters, and whether or not this type of water heater is appropriate for you and your family.

What is an instant hot water heater?

An instant hot water heater is a heating system that warms water on-demand, rather than storing hot water in an insulated tank. That means instead of measuring the volume of hot water produced by the unit, as we might with a storage water heater, we measure flow rate in gallons per minute. Typical units can heat between 2 and 5 gallons of hot water per minute. Instant water heaters use either electricity or natural gas to rapidly heat water as you use it. That means your water heater sits idle until you need it to work. Storage water heaters, by comparison, heat a large volume of water and store it for instant access as needed.

Gas instant hot water heaters are typically less efficient than electric, but usually provide more gallons of hot water per minute. Electric models are extremely efficient — up to 99% of the electricity gets converted directly to heat. Compare that to older storage heaters that can operate at as little as 67% efficiency, and you start to get an idea of why many families are interested in switching to tankless instant heaters!

Instant water heater pros and cons

Instant water heaters aren’t necessarily better or worse than a conventional storage system. They’re just different! Whether or not they are appropriate for your family depends on what you need and expect from your heater.

First, let’s look at what instant water heaters are good at. Because they don’t need to store dozens of gallons of water, they’re much smaller than a storage heater, and can be mounted on the wall of your kitchen, bathroom, or wherever else it’s needed. Gas models typically last longer than a storage heater, as well — sometimes longer than 20 years with proper maintenance.

Another benefit of an instant heater is the speed with which they can heat your water. In many cases, you’ll have hot water within seconds of turning on the tap. This reduces wasted water and improves home comfort and convenience — no more standing around waiting for the shower to heat up!

Instant hot water heaters are typically cheaper to operate over the span of their existence than storage heaters. They use far less energy than older storage units per gallon of water heated. Since many tankless heaters need to be replaced half as often as a traditional storage water heater, the increased up-front cost of installation will usually be offset over the life of the unit. Instant water heaters are also safer. There is less risk of flooding or water damage since these units don’t have a tank that could spring a leak. They’re also easy to shut off if you leave for vacation and don’t require draining if you plan to be away for a long time.

Finally, more than one instant water heater can be installed in a single home to provide dedicated hot water to each appliance or faucet. You might also add one to a storage heater setup to provide more efficient hot water for a single purpose. While it can get expensive (see the cons below), multiple water heaters can ensure that your whole family has instant access to hot water at all times, while still saving on your energy bill.

Instant water heaters aren’t perfect. The up-front cost of installation can be quite a bit higher than a similar storage system, particularly for natural gas powered units, which require additional ventilation for safety. Since they don’t store water, they may fail to produce enough hot water if multiple appliances or faucets are running at once. As we mentioned earlier, adding additional heaters for each area of your home can rectify this issue while providing all the benefits of a tankless setup. Of course, this increases the initial setup cost by quite a bit.

Should my family consider an instant heater?

Based on the information above, you probably have a good idea of whether or not an instant hot water heater is appropriate for your home. If your water heater is in need of replacement, you should definitely weigh the pros and cons of upgrading. For smaller homes or families that don’t use too much hot water, an instant water heater system makes a lot of sense. For large homes or heavy water users, you’ll need to weigh the added cost of installation versus the potential savings and convenience.

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