Faucet aerators are great for water and energy savings, but when should you use them?

Businesses and homeowners pay for water three times—once to buy it from a utility, once to heat it using natural gas or electricity, and once to dispose of it as wastewater. That’s why high-efficiency faucet aerators can save business owners and homeowners a lot of money. But not every situation is a good fit, so it’s important to keep a few things in mind. Keep reading to learn the basics!

  • Flow Rate: If you already have a low-flow aerator, it may not be effective to replace it. Check this by reading the side of the aerator (the metal ring where the water comes out). If your flow rate is more than 1.5 gallons per minute (gpm), you should replace it.
  • Maintenance: Aerators occasionally need to be rinsed out since sand and particulate can build up, restricting the flow. Plan to replace them periodically to maintain good performance.
  • Task: Aerators may or may not be a good idea, depending what you’re using water for. This guide gives a general rule to gauge your needs:
    • Volume-based tasks: If water is used to fill a container (e.g. pasta pots or dish-washing sinks) aerators will not save water or energy. Instead they will increase the amount of time it takes to complete the task. In this case, don’t use an aerator.
    • Flow-based tasks: If running water is used for washing (e.g. hands, dishes or food) then an aerator is the perfect solution. In this case, use a 0.5 gpm aerator.
    • Combination of tasks: If water is used both for flow- and volume-based tasks (e.g. household kitchen sink) then you need to find a happy medium. A higher-flow aerator will save energy and water without hindering volume-based tasks. In this case, use a 1.0 gpm aerator.
  • Hot Water Supply: A common complaint with low-flow aerators is that it takes too long to get hot water. This is because the pipe from the water heater to that sink is a “dead head” — it goes only to that sink and nowhere else, requiring cold water to be dispelled first. With a 0.5 gpm aerator, it takes 2 minutes to purge 1 gallon of cold water from the pipe. While this is longer than most people take to wash their hands, if you are not in a food service business (or other sanitary business) where a specific water temp is regulated by law, then this is not a significant concern. Clean hands are achieved with soap & water, vigorous rubbing and running clean rinse water over them. Plus, most people are willing to wash their hands in cool water. You should also consider the following:
    • Insulating pipes: This cheap fix will keep the water in your pipes hot until it’s ready for use.
    • Piping design: Larger buildings are often piped with a closed-loop system that has a pump to keep hot water recirculating throughout the building at all times. Hot water supply is not typically an issue with this design. Newer buildings might also have an electric booster heater by sinks that are located far away from the water heater, so hot water supply shouldn’t be a concern.
    • Food service: Minnesota Food Code (Chapter 4626) requires that the water temperature at hand sinks reach 110 degrees. Some inspectors and jurisdictions may require that the water reach that temperature within a certain time limit. Typically, in high use situations, the length of time to reach temperature won’t be an issue (especially with insulated pipes).

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