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Tips, considerations in selecting a hot water tank

Posted by Tony Mauro

When selecting a new hot water tank, energy efficiency is important. But other aspects of your home and lifestyle should be considered, or you may end up being disappointed in your product choice.

Recovery rate

If your household has a tendency to empty the tank frequently, recovery rate becomes a very important factor in your purchase decisions.

Recovery rate refers to the speed at which a tank that has been drained will bring the water back up to the desired temperature. Gas usually provides the fastest recovery rate, followed by electric, then heat pump water heaters.

Flow rate

This one applies mainly to gas tankless water heaters.

By design these units typically don't engage the heating unit for low flows or draws. Most of the draws in a house are this type of a flow – quick and frequent. There are newer models of tankless units that have a very small tank inside the unit to service these demands, but these units do cost more.


Keep in mind that if you buy an advanced hot water heating system that is much more then a standard high efficiency unit you might never pay back the investment.

Do a little math. Take the cost of upgrading to a more advanced system, then divide it by the savings you'd expect for the year. If the payback period is greater then the life expectancy of the unit, it might not be an economical investment.

A solar unit might also sound like a good option, but could require structural work to the roof and piping to get the unit installed. Keep this in mind when you are shopping around, and always ask questions.

Complexity & maintenance

If the unit is more complex, such as a tankless or heat pump water heater, make sure you know there are people in your area who can service the unit if there are problems.

Side considerations

Newer technologies usually have things to consider that didn't exist with older products. Heat pump water heaters output cool air as part of the process to heat the water. If your tank is in an area that is heated, then this might affect the comfort in the winter, but help cool your place in the summer.

What's best for you?

The unit you select might not be the same as what your neighbour bought for her retrofit, because of differences in the way your family uses hot water. It's always a good idea to consider the options and how they might fit in.

Energy efficiency is great and should always be at the forefront of your thinking, but don't neglect the other aspects. It might sour your view on energy efficient products.

For a look at one B.C. homeowner's experience – after dealing with the mess from an old, leaking tank – see Nola Poirier's post Getting into hot water in cold weather.

Tony Mauro is a Power Smart engineer and regular contributor to Unplug This Blog! and futureshop.ca's BrandTalk blog.