Weighing the pros and cons of tankless water heater ownership is tricky. Endless hot water, additional storage space and lower energy bills are a few up sides about going tankless. But, those benefits may not be enough to offset the higher purchase and installation costs.
Are tankless water heaters really more efficient?
That depends how you define efficient. Heating water uses gas or electricity. It costs the same to heat a given volume of water no matter which type of water heater you choose. While a tank water heater may use up to 50,000 BTU of gas heating water in its holding tank, a tankless will consume about 175,000 BTU as it heats water on demand.
On demand heating means you’re not heating (and probably re-heating) water in a tank that may go unused. On the other hand, by the time you go through an entire tank of hot water, the actual heating cost is nearly break even. Depending how you use hot water, a traditional tank water heater may be more economical. That’s especially true when it comes to up-front costs.
Long-term tankless water heater savings
Tankless water heater savings is a slow-and-steady kind of thing. Because they’re two and three times more expensive than traditional water heaters, a tankless water heater takes longer to pay back your investment. A typical tank water heater lasts about 10 years. A tankless water heater, on the other hand, is estimated to last about 20 years.
Because internal components can be replaced, a tankless unit’s service life can be further extended. That’s not the case with a traditional water heater. The most common failure is the tank itself which means having the entire unit replaced.
Annual maintenance is crucial to the life of a tankless water heater. Flushing pressurized vinegar through your system, which is usually work for professionals, keeps the heat exchanger clean and operating at peak efficiency.
Tankless water heaters: endless, not instant hot water
Unless you choose a point-of-use tankless water heater, hot water still has to travel through your plumbing before arriving for use. Once it arrives, however, the water will stay hot as long as you use it—sorta. Even tankless water heaters have limits. Turning on multiple showers and doing dishes at the same time may exceed the throughput limit. When that happens, your water temperatures will cool.
Tankless water heaters in space
An often overlooked benefit of going tankless is the space they save. A 40-60 gallon water heater is about five feet tall and two feet around. Meanwhile, a tankless water heater is only about two feet square and less than a foot deep. Even if it’s in your attic, that recovered real estate can come in handy.
Tank or tankless?
Convenience and preference, not efficiency and economy are the most common factors driving the choice of a tankless water heater. Weighing these ups and downs relative to your specific needs will lead you to the best possible choice.