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The Ultimate Tankless Water Heater Quiz
by Staff
Tankless or not - that is the question. Will you get hotter, purer or more immediate water if you switch to a tankless water heater system? And will you save on water, energy or your monthly bill if you do? Keep cool as you take this hot hot-water quiz.

How much time does it take for a tankless water heater to heat the water?

  • It takes as long as a conventional water heater.
  • It works immediately, heating the water as needed.
  • It takes about 90 minutes.

In which regions have tankless heaters been in use for a while?

  • Europe and Japan
  • Australia and Asia
  • China and the U.S.

Are tankless water heaters cost effective?

  • Not really; they are expensive to install and they cost more per month.
  • Yes, they are cheaper to install and cheaper to run.
  • They cost more initially than a conventional one, but they save you a lot on monthly bills.

What are the main advantages of a tankless water heater over a tank heater?

  • It can be used to both heat water and circulate hot air through your home.
  • It is far easier to install and it conserves water.
  • It lasts longer than a tank heater, offers hot water continuously and takes little space.

What is the function of "standby heat loss"?

  • to keep tank water heated even when it is not needed
  • to keep the pressure within the water tank at a standard level
  • to keep the water within a tankless system on standby, ready for heating as necessary

Where would you find an "on demand" water heater?

  • in both tank and tankless water heating systems
  • only in a tankless water heating system
  • only in a tank water heating system

How does the water heat up in a tankless system?

  • A manual pump is operated on demand to heat the water as it pumps out through the faucet.
  • You turn on the hot water faucet and, as it flows out, the water heats up via a heat exchanger, generated by electric coils or gas burners.
  • Pressure in the pipes builds up to allow for a pre-set temperature to act on the water.

What is the use of point-of-use tankless water heaters?

  • They're used because they can hold a large amount of water in the pipe at any given point of time.
  • They're not much use at all - actually they're quite pointless.
  • They're used because they're small systems and can be installed tidily near the faucet.

What do whole-house water heaters usually run on?

  • electricity or propane
  • electricity or natural gas
  • natural gas or propane

What is the problem with lag time?

  • It wastes water because of the distance between the water source and the outlet.
  • It would necessitate a delay between the turning on of the faucet and the outflow of water.
  • It might jeopardize the heating system because of the time loss involved.

Why do some people use aerators?

  • to aerate the water so that it tastes purer
  • to limit the water flow
  • to aerate the water in order to maximize the mineral content

The 1992 Federal Energy Policy Act stipulated a set water flow of _____

  • 0.5 gallons (1.9 liters) per minute at 20 pounds per square inch (PSI) for household outlets
  • 1 gallon (3.8 liters) per minute at 40 pounds per square inch (PSI) for household outlets
  • 2.2 gallons (8.3 liters) per minute at 60 pounds per square inch (PSI) for household outlets

In order to determine what water heater would be suitable for you, what two factors should you take into account?

  • the temperature rise and water flow rates
  • the purchase price and installation fees
  • the amount of water you're likely to need and the water pressure limit

How do you know what is your ground water temperature?

  • You ask the installation expert.
  • You measure it with an industrial thermometer.
  • It's about the same as your mean annual air temperature.

With a whole-house water heater system, what would happen if you turned on all the faucets at once?

  • You would still have hot water throughout, but it would be split among the faucets.
  • You would not have sufficient hot water for them all.
  • The system might crash due to overload.

Which of these are benefits of a tankless water heating system?

  • They're powerful, cheap and eco-friendly.
  • There's no potential flooding from a burst tank, they're cost effective and they never run out of hot water.
  • They are suitable for all locales and can be installed by a layman.

Are there any drawbacks to the tankless water heater?

  • Yes, but the drawbacks are minimal.
  • Not at all.
  • Yes. They cost more, may require additional gas lines or electricity circuits and may involve lag time.

What cost could be expected with the purchase of a whole-house tankless system in a U.S. home?

  • an initial outlay of $500 to $1,000
  • an initial outlay of $1,000 to $2,000
  • an initial outlay of $2,000 to $3,000

What is the average lifespan of a tankless system as opposed to a tank water heating system?

  • the same for both: 15-20 years
  • 10-15 years for a tankless system vs. 20 years for a tank one
  • 15-20 years for a tankless system vs. 10 years for a tank one

Can you get a rebate in the U.S. on the cost of a tankless unit?

  • usually about $300
  • no
  • usually about half of the purchase price