how to size a commercial water heaterRunning a kitchen, hotel, apartment building, or any business without a water heater would be a nightmare. Running one with an incorrectly sized water heater can be just as bad. Your business will suffer if staff or tenants can’t access hot water when they need to. Yet, if you buy a tank that is too large, you’ll end paying more in utilities than you should. Thankfully, you can be sure you’re getting the right size water heater before you make the investment. Here is how you can size a commercial water heater.

Information to Gather

Businesses use different amounts of water and in different ways. A commercial kitchen that is open 24 hours a day will need small amounts of water consistently throughout the day. A hotel may need a huge volume of water in the morning and a moderate amount throughout the rest of the day. In order to understand what your water needs are, you should collect this information:

  • Your hours: Businesses that are open more will need more consistent hot water.
  • Peak demand: Is there a certain time when your business uses the most water?
  • The number of fixtures: Include any fixtures that might need hot water, from showers and sinks to dishwashers. Also calculate fixture demand or how many gallons they use per hour.

With these factors in mind, you can assess what kind of capacity and recovery rate you’ll need from your water heater.

The Water Heater’s Capacity

Your water heater should have the capacity to meet maximum hot water usage, also called the dump load. This is the total demand from every fixture. Having this amount of gallons available from the water heater ensures that you can meet peak demand. Every fixture could be turned on at once, and you would still get hot water from each.

The Water Heater’s Recovery Rate

Here’s where things get a little complicated. How much recovery rate do you need from your water heater? Or, how much hot water does it need to generate per hour to refresh it’s stored capacity (which we determined above). This number should be less than your heater’s capacity. Afterall, what are the odds that all of the fixtures in your property will run for more than an hour?

Instead, you’ll need to figure out how much water you need to be available every hour and what kind of recovery rate your tank size will need in order to keep this water ready. Businesses that use a ton of water in a two or three-hour period may find that they need a very large recovery rate. Businesses that have more moderate demand on their water may only require a water heater that recovers slowly, relying on having excess from the initial full tank to fill in the gaps.

Ask the Experts

Ultimately, it would help if you worked with a professional plumber to determine what size of water heater you’ll need. They can take into account factors that are harder for you to assess, like what kind of space you have for the tanks and if a tankless would better suit your needs. They will also consider what kind of venting can be installed in your building and how the local climate might change your hot water needs. Whether you need a water heater repair in Manteca, Mountain House, Modesto, or elsewhere in the Bay Area, reach out to us today for commercial water heater installation.