When a representative from one of the major tank-less water heater companies came down from Orange County to show me how to get rich selling their products, I was admittedly skeptical. I liked the general concept, but I already knew how much Tanklessthey cost and couldn’t imagine a scenario where they would be a money saver. The more he hyped his product, the more entrenched became my original misgivings. As it turned out, my instincts were correct and following are the details of what I learned:

  1. If you have a situation where hot water is never used during the day and at night after bedtime, the pilot light on a conventional water heater stays lit and ignites the burner whenever the water temperature in the tank decreases. This unnecessary heating of water that is not being used is eliminated by the efficiency of a tank-less model. Maximum savings for eliminating this situation is estimated to be $120 per year. Read that again…$120 per YEAR! You might think, “What’s wrong with that?” Nothing, but you have to consider that the manufacturer requires an annual service on the unit to keep the warranty in effect. Cost of such maintenance (unless you get a pump and learn to do it yourself): Around $120 per year.
  2. Since tank-less water heaters require a gas line that can accommodate the large burners that they use, the typical ½” gas lines that are used for tank type water heaters are inadequate and must be replaced by a larger size, depending on the size of the tank-less unit. Sometimes the only way to achieve the required size is to run a dedicated line all the way from the gas meter.
  3. Existing water heater vents cannot be used for the tank-less units which require a 4” stainless steel vent.
  4. To use a re-circulating pump to achieve instant hot water would cause the tank-less unit to remain burning, therefore it is impractical and costly to get instant hot water to remote fixtures.
  5. The wholesale cost of a tank-less water heater compared to a conventional water heater delivering the same capacity is approximately two and one half times.
  6. A typical conventional water heater installation that would typically cost under $1000 will, generally speaking, run $2500-$4500.

If saving space and environmental issues are your primary concerns, then a tank-less model may be for you. Once the heater is in place, fuel and maintenance costs are comparable. We have installed many of these units and they are dependable and efficient. These comparisons become much more attractive when installing tank-less units on new construction, where vents and gas lines have to be installed, anyway. Since the tank-less models are relatively recent and have 10 year warranties, we have yet to determine longevity of their active components and their availability and cost. Truth is, whenever I outline the preceding issues, I almost always sell a conventional water heater.

Gary R. Tanner