Purchasing a hot water heater is an investment that should last for many years. While conventional units with tanks that hold and heat large quantities of water last about 13 years, tankless or “on-demand” heaters — either gas or electrically heated — can last up to 20 years.
What They Do
Tankless water heaters provide hot water in which you want it — like the kitchen sink — by heat the water fast when the faucet is turned on. This can conserve water costs if you typically have to conduct water for quite a while to get it heated. It can also save on heat costs; rather than maintaining water heated continually, it’s heated upon request.
Why They Last
Standard water heaters are subjected to continual moisture, which causes deterioration. While some parts could be adjusted to extend the life of the heater, water quality and mineral content can also influence how fast corrosion occurs as well as the heater remains in working order. Tankless models can be affected by water quality but have significantly less exposure to rust.
At this time, residential versions of tankless heaters can provide 5 gallons of hot water per minute, heated to 90 degrees. This won’t be enough hot water for a family who needs hot water for showers, laundry plus a microwave — especially if more than 1 item is run at precisely the exact same moment.