How Do On-Demand Water Heaters Work and How Long Do They Last? | PJB Mechanical

How Do On-Demand Water Heaters Work and How Long Do They Last?

On-demand water heaters, also known as tankless water heaters, operate efficiently by heating water only when you need it. When a hot water fixture is turned on or an appliance requires hot water, the tankless heater detects the demand and heats the water instantly. This eliminates the need to store and reheat water continuously, reducing energy consumption and operating costs.

Unlike traditional tank-type water heaters, which have a limited supply of hot water, tankless water heaters offer an unlimited supply. You’ll never run out of hot water, even when filling a large bathtub or accommodating multiple showers. These compact units, approximately the size of a carry-on suitcase, can be installed virtually anywhere inside your home, freeing up valuable space.

Energy Efficiency and Savings

According to the Energy Commission, tank-type water heaters consume about 25% of a household’s total energy consumption. Switching to a tankless water heater can result in up to 50% less energy usage for water heating, leading to significant annual savings.

Moreover, tankless water heaters have an impressive lifespan of 20 years or more, which is two to three times longer than traditional tank-type heaters. This long life span not only saves you money in replacement costs but also reduces the environmental impact.

PJB Tankless Water Systems oinfographic

Expert Opinions

At PJB Mechanical, we often get asked about the benefits of on-demand gas water heaters. On-demand gas hot water heaters have been popular in North America for over a decade, and PJB Mechanical has installed numerous units with no complaints.

One common misconception is that on-demand water heaters provide instant hot water. While they don’t offer instant hot water, they provide continuous hot water, ensuring everyone in your household has access to hot water whenever they need it. Unlike traditional tank-style heaters, on-demand units don’t store hot water, saving you money on heating costs.

These units require minimal maintenance and offer a useful life of over 20 years, surpassing the lifespan of traditional hot water tanks.

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