Select the Right Size of Water Heater

Hot water accounts for about 25% of the average home energy costs. and Purchase what suits your family's needs and at the same time save money.

Simultaneous use of the hot water system is one of the fundamental determining factors. The number of people in your home combined with how and when they use the hot water.

Let’s discuss it further.

Determine the size you need

Sizing Storage Tank & Heat Pump Water Heaters:

To properly size a hot water tank, calculate peak hour demand and compare it to different models' first-hour ratings. The hot water tank should have a first-hour rating within 1-2 gallons of peak-hour demand.

First-hour rating is the gallons of hot water the tank can supply per hour after it has been filled. This depends on gallon capacity, size, and source of heat.

How to calculate peak hour demand:

1. Determine what time of day your household uses the largest amount of hot water.
2. List of different ways how the hot water is used at this hour.
3. Calculate the total gallons used in this hour by multiplying gallons used per activity by the total times completed (see example chart below).

Comparing Water Heater Size to Space Available

Dimensions of the latest water heaters are typically 2 inches wider and 2 inches taller than old models.  If a standard-size water heater can’t fit the space, consider short and tall alternatives.  A tankless water heater is the best choice when space is an issue.

The size of the hot water system you need primarily depends on your family’s peak usage period and when you use additional hot water, as opposed to the number of bathrooms or people. Taking time to consider your actual usage before buying can save you energy and money.