What size hot water heater do you need?

Published On: July 10, 2017Categories: Uncategorized

rheem-hot-water-heaterWhen the time comes to replace your hot water heater, you’ll need to decide what size is right for your family. If you get a tank that’s too large, you’ll drive up the cost of your utilities and waste money. On the other hand, get a tank that’s too small and you’ll run out of hot water at a time when you need it the most, like when your in-laws are staying over. Here are some considerations to keep in mind when you’re deciding on what kind of water heater to buy.

Storage Tank Water Heaters

The typical storage water heaters have to hold enough water in their tank to meet your family’s needs. Every water heater has a first hour rating (FHR), and you can use this number as a way to determine if a storage tank is large enough to handle the job for you.

Calculating your family’s optimum FHR is easy. First, count the number of people in your home. Now if you’re buying a water heater and you don’t know how many people will end up living in the house, a good rule of thumb is to add one person to the number of bedrooms in the home. So for a four-bedroom house, you’d calculate based on having five people live there. Multiply this number by 12 gallons, and that is the FHR. So in a three-bedroom home that has four people, the FHR would be 48 gallons (4×12 gallons).

Now when it comes time to buy, a hot water heater that has an FHR within a couple gallons of the number you just calculated should meet your family’s needs. However, you might just want to adjust the figure, though, if you have a soaking tub or some other special consideration. When all is said and done, here is what the math tells us should work for you:

  • 1-2 people need a 30-gallon water heater
  • 2-3 people need a 40-gallon water heater
  • 3-4 people need a 40-50 gallon water heater
  • 5 or more people need a 50-80 gallon water heater

Now before you make your final decision, there is one other consideration to make and it’s a big one. Should you stay with a traditional storage hot water tank or go with a tankless water heater?

Tankless Water Heaters

A tankless water heater’s capacity isn’t measured in gallons stored but in flow rates. A tankless water heater’s flow rate should be equal to the peak demand your family is likely to place on the system.

To see what size tankless water heater you need, list the water devices you think you’ll be using at the same time. Add up the flow rates of each. The tankless water heater should have a flow rate equal to the number you arrive at. Many models have a maximum flow rate of 3.5 gallons, which is enough for a sink faucet and shower.

Where to Get Sound Advice

As you can see, replacing a hot water tank gives you some options that you may never have considered in the past. It’s worth your time to investigate what kind of hot water heater is best for you and how big a water heater you need.

We can help!

If you want help calculating what size water heater your family needs or need more information about the pros and cons of a tankless water heater, contact us at The Plumbing Source. We’ll go over the math with you and make sure you find a hot water heater that’s the perfect size for your family.

Call today! 877-768-7239.

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