The Great Water Heater Temperature Setting Debate

Much has been discussed over exactly what is an optimal water heater temperature level setting. Many sources, consisting of ENERGY STAR, offer the energy conserving elements of temperature levels of 120 degrees or lower. And yes, there are cost savings to be had, however realistically for those whose current setting is closer to the standard factory preset temperature of 140 degrees.

Conversely, fewer share info about the possibility of contracting Legionella bacteria with a lower setting, particularly with a temperature lower than 120 degrees. OSHA specifies some outstanding precautions for preventing this.

Valid conclusions are that it is something that each family should weigh in regards to potential health concerns mainly. For those with kids or with elderly people in the house, a higher setting can be a water scalding concern. Conversely, those susceptible to contracting respiratory infections, a higher setting ought to be used.

Views: 153

Tags: Debate, Heater, Nashville, Repair, Setting, TN, Temperature, Water

Comment

You need to be a member of Home Energy Pros to add comments!

Join Home Energy Pros

Comment by Phil Luther on March 1, 2014 at 3:50am

Excellent questions Brad!  Let me share a document from the World Health Organization here that goes into much detail in terms of your first two questions.  I personally concur with final conclusion of saving energy from turning up the water heater setting.  I have young children so for me the risk of too high a setting is my determining factor on the topic.

Comment by Brad Cook on February 28, 2014 at 3:39pm

And what, exactly, is the risk of Legionella in your water supply? 

How does the Legionella get into your water heater (water supply)?

If 140 deg. is a burn hazard and a mixing valve is required (which often fail in HOT position), aren't you now contaminating your hot water with untreated (cold) water at the mixing valve?

I do not find any conclusive studies linking Legionella to domestic water systems in the US, particularly in private wells. In addition, according to the NIH (National Institute of Health), UV light is as effective as heat in killing Legionella bacteria. So why are we wasting so much energy cranking up our hot water temperature?

Home Energy Pros

Home Energy Pros was founded by the developers of Home Energy Saver Pro (sponsored by the U.S. Department of Energy,) and brought to you in partnership with Home Energy magazine.  Home Energy Pros is sponsored by the Better Buildings Residential Network.

Latest Activity

Profile IconJerrad Pierce, tracylee, Nevada Heating and 4 more joined Home Energy Pros
12 hours ago
Shawn Weeks posted a blog post
12 hours ago
Kirsten Richnavsky's discussion was featured

New BPI Standard for Conducting Energy Audits Published as an ANSI Standard!

The Standard Practice for Basic Analysis of Buildings defines the minimum criteria and specific…See More
14 hours ago
Daniel Beauchemin's photo was featured

Residential installation of a ThermoDrain TD342B

DWHR HERS Index Score Credit Calculation ProcedureUntil such time that DWHR system calculations…
14 hours ago
Tom White's 2 videos were featured
14 hours ago
Corbett Lunsford's video was featured

New Home FAIL: Infrared Secrets Revealed

Building forensics guru Corbett Lunsford can show you what's behind the walls of any house- or are you afraid to find out? Don't be! It's all generally fixab...
14 hours ago
Jose Macho's blog post was featured

Why Don't Homeowners Spend Money on Energy Saving Upgrades??? Blame "Cognitive Biases"

A great transcript from a recent NPR "Morning Edition" broadcast about a recent California survey…See More
14 hours ago
Elizabeth Guinn's discussion was featured

ERV in need of backflow preventer.

I installed an ERV on my last job with the intake and exhaust utilizing 6" round hard duct.  I have…See More
15 hours ago

© 2015   Created by Lawrence Berkeley National Laboratory.

Badges  |  Report an Issue  |  Terms of Service