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About Tankless Water Heaters

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Is it time to get a new hot water heater? If your old water heater is going out, or you're tired of the inefficiency and high costs of your current water heater, it may be time to take a look at a tankless water heater. Once the novelty item no one trusted, tankless water heaters have finally found their place in the American market, proving to be quick, dependable, and energy-efficient.

A Newfangled Idea?

Many Americans are under the impression that tankless water heaters are a recent invention. But in fact, tankless technology has been in use in Japan and parts of Europe since the 1920s! The technology behind tankless (or "point of use") water heaters was brought to the United States by a company called Myson, but it was only around the early 2000s that tankless heating began to experience a substantial rise in popularity.

Why Get Rid of the Tank?

Traditional tank water heaters have been around for years - why get rid of a good thing? The simple answer is: they aren't perfect. Standard water heaters have their share of problems, most annoying of which is their propensity for running out of hot water.

Everyone has probably experienced it at some point: that sinking feeling when the shower water goes from hot to warm, followed rapidly by the chill of cold water. This happens because the water heater's tank can only hold so much hot water - typically around 40 gallons. When your hot water demands exceed the supply (all too easy when you have a bunch of people that need to shower, or run water-intensive appliances at shower-time), there's nothing that can be done - new water must be heated, which we all know can take a while.

The broader problem with tank systems is something called "standby heat loss". No matter how great the tank's insulation is, the hot water inside will give up its heat over time - that's just how the universe works. The only way to keep that water hot is to regularly warm it up - a constant cycle that consumes energy and costs you money. Standby heat loss typically accounts for 10-20% of total annual water heating costs. In many homes with standard tank heaters, the energy consumed for heating water is even greater than that used for heating the home itself!

Quick Note: There are places where ditching the tank may not be the best idea - in earthquake-prone areas, tank water heaters can serve as an emergency water source!

Is Tankless Better?

Tankless water heaters were designed to avoid the shortcomings of standard heaters, providing a more energy-efficient and sensible way to have a steady hot water supply. Utilizing powerful gas burners or electrical elements, they're able to rapidly heat water at the time of use, as opposed to storing (and perpetually reheating) it for eventual use. Heating water only when you need it makes sense, and eliminating standby heat loss almost always results in lower energy bills. Less energy use = less impact on the environment, which is always a good thing.

In addition to avoiding standby heat loss, tankless heaters are also smarter in how they use fuel (be it gas or electrical energy). By modulating their fuel use, these units use only what's needed to heat water at the flow rate actually being experienced. If you open up a sink faucet that's drawing 1gpm, less fuel is used to heat that water than would be used for a tub faucet running at 5gpm. As a result, it's not uncommon to see fuel-use reductions of up to 50% compared to a tank heater.

Early tankless heaters were plagued with producing too little hot water, especially when multiple demands were placed on them. Most produced hot water at a rate of only 2-5 gallons per minute - good enough for a shower, maybe. Today's units are vastly superior, with production rates of over 10gpm available. Now that they're able to meet the demands of a typical household, the only substantial barrier to the widespread adoption of tankless heaters would appear to be their (generally) higher price.

Which is Best for You?

Tankless water heaters vary in size (from small, point of use heaters to larger, whole house options) and fuel source (natural gas, propane, electricity). Whether you use gas or electric will depend on the availability and cost of fuel in your area. Everything else depends upon usage habits, and the fixtures being used. To help you figure out what would work best for you, take a look at our selection guide.


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Frequently Asked Questions

Q. "Will an instantaneous water heater save me money on my utility bills?"
A. In many applications you can see a savings. There are some variables that could reduce the amount you save. One example is you will not run out of hot water, so longer showers could cut into your savings. Also, the cost of electricity, propane and natural gas in your area will affect the amount of money saved. The higher the cost for the energy type used to heat your water, the quicker you can recover the higher initial cost of installing a tankless versus tank style water heater.

Positives:
  • You will never run out of hot water. "You want an hour long shower? No problem!"
  • Electric units can be installed at the point of use.
  • You're not paying energy costs to heat water 24 hours a day.
  • They're easy to install.
  • Our electric units don't require a T∓P valve (no tank!) - if code allows
  • Installing a tankless water heater can indeed be a bonus to the environment (why should we choose wastefulness when we're talking about finite natural resources?)
Negatives:
  • They all need a minimum flow rate & pressure to turn on.
  • The faster water flows through them, the lower the temperature rise. So, if you expect to take a shower while the clothes washer is running, you will need to select a unit sized to your maximum hot water flow requirements. (Gas units generally handle this a little better than electric models)
  • Electric units need heavy gauge wire. Example: the 9.5kw must have 8ga wire and a 50amp breaker.
  • Gas units need a much larger, special flue pipe and larger gas supply than a conventional water heater.
  • At times they can produce very hot water. It's easier to get scalded.
  • Gas units are more complicated than a conventional water heater.
  • With some brands, parts are hard to find (not a negative if you originally purchase from us, as we like to carry parts for the units that we sell).
Summary: Tankless water heaters have their place. They're not "the answer" to every hot water need, but if they're used correctly, they can be the solution to many of them.

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