Results 1 to 6 of 6
  1. #1
    Join Date
    Nov 2010
    Location
    indiana
    Posts
    185
    Post Likes

    hot water heater setpoint

    What is recommended for hot water heater setpoint in a commercial building? There are a couple of new buildings where I work, one is a science building and one is an art building for a middle/high school. The hot water is not used for heating spaces. No water is used for showers or food preparation. They do have circulator pumps. I dont want kids to scald themselves but I got spooked after reading about legionairres and the business manager is always looking for ways to decrease energy costs. Ive heard 120, 130, and 140 from different sources. What do you think is best? Thanks

  2. #2
    Join Date
    Jun 2012
    Location
    Northern NV
    Posts
    1,614
    Post Likes
    140F to kill Legionella. Tempering valve to keep scalding at bay..

  3. #3
    Join Date
    Oct 2009
    Location
    Raleigh, NC
    Posts
    901
    Post Likes
    The chance of contracting legionella from a hot water tank is miniscule, especially if the water system is disinfected. If you are on a city water supply, there is no worry. If you insist upon worrying about it, the entire hot water system, all the way to every tap, must be maintained up to at least about 125F to suppress or kill legionella colonization. Think about it. How many confirmed reports of legionaires disease do you hear of that are attributed to hot water storage? Set your tank to 120-125. If you really want to save energy, put your circulation pumps on timers so the can be stopped at night.

    Sent from my Pixel 2 using Tapatalk

  4. #4
    Join Date
    Aug 2002
    Location
    Southold, NY
    Posts
    20,849
    Post Likes
    Quote Originally Posted by MicahWes View Post
    The chance of contracting legionella from a hot water tank is miniscule, especially if the water system is disinfected. If you are on a city water supply, there is no worry. If you insist upon worrying about it, the entire hot water system, all the way to every tap, must be maintained up to at least about 125F to suppress or kill legionella colonization. Think about it. How many confirmed reports of legionaires disease do you hear of that are attributed to hot water storage? Set your tank to 120-125. If you really want to save energy, put your circulation pumps on timers so the can be stopped at night.

    Sent from my Pixel 2 using Tapatalk
    I wouldn't say minuscule maybe unlikely so it has to be corrected. Showers are a leading cause! ASHRAE recommendations are 140°F minimum for the tank and supply loops.

  5. #5
    Join Date
    Jan 2012
    Location
    Broomall, PA
    Posts
    2,373
    Post Likes
    Might not be many 'confirmed reports' but it's also misdiagnosed because it can mimic other illnesses.
    I also don't agree with this statement at all:

    "...If you are on a city water supply, there is no worry..."
    Uh...Google it yourself!

  6. #6
    Join Date
    Aug 2002
    Location
    Southold, NY
    Posts
    20,849
    Post Likes
    Quote Originally Posted by STEVEusaPA View Post
    Might not be many 'confirmed reports' but it's also misdiagnosed because it can mimic other illnesses.
    I also don't agree with this statement at all:

    "...If you are on a city water supply, there is no worry..."
    I missed that

    X-2

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •