Hot Water Tanks – Needs and Comparisons

Quite simply, who needs what? That is the question! There are ways of pitting one hot water tank against another. But realistically, what does that mean to the average consumer? With utility bills constantly on the rise, any logical person would want “the least cost, maximum efficiency”.

If you’re out looking for a new hot water tank, chances are you’ve either moved to a new place that requires one, or are planning to replace the one in your current home. A common question most people ask themselves is: “The old one was 30 gallons, and it broke. Buying a 40 gallon tank or larger ought to solve the problem”. Thinking in terms of gallonage is often not the most viable solution. Instead, think in terms of Btu input or first-hour recovery. Allow us to elaborate:

Btu input

These terms generally dictate how rapidly a tank can heat water. A boiler that heats up an entire apartment building or skyscraper, at times, has no storage at hand. It relies on a series of copper tubes running through a very hot fire. Water is heated in an instant. Powerful commercial water tanks have little capacity; a 75, 000 Btu, 100 gallon light commercial water tank is a good deal and less potent than a 25,000 Btu, 65 gallon tank.

First-hour recovery

This essentially combines the hot water a tank can hold with what it can heat in one hour. Used concurrently with the ‘yellow federal energy sticker’, it provides an effective means of comparing different tanks, along with the Btu input.

Now, let’s get into some specifics:

  • Buy a tank that comes with a magnesium anode; add a second anode of the combo type that goes in the hot outlet port; keep an eye on them
  • Alternatively, you can buy a tank with an aluminum hex anode and replace it with magnesium; repeat the same as above
  • Add a magnesium combo anode to the hot port
  • Rheem/Ruud/Richmond/General Electric always use magnesium rods

What’s interesting to observe here is there is no bump on the hex head. Any other manufacturer would have a bump on the hex head. This being present is an important sign to look for; it assures you the anode is a magnesium one, and you’re buying among the best quality that’s available. This may be big or small though, which shouldn’t be a cause for concern. As for Rheem, you’ll need to buy the combo from them directly; they’ve engineered their heaters to the highest standards, and accept nothing less.

By contrast, aluminum rods are much softer and more bendable. Dry aluminum appears brighter, while magnesium appears much duller. This information may not be useful if you’ve never had a side by side look at both, but it’s good to know!

If you ever find yourself in a situation where you’re adding an anode to a new tank, make sure both rods are the same metal. Otherwise, the magnesium rod will be consumed more rapidly while an aluminum one is present. You’re not getting as long a life.

Keep checking back with us, for a read on some options we explore pertaining to installation.

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