I have been lurking here for a while and have found this site and the people here to be incredible helpful. Let me start by saying I am a homeowner. Plumbing, heating, and electrical is not DIY IMO
My DWH is your traditional Bradford White 75 gallon gas fired heater. I keep reading posts here about setting the water temp at 140 to ward off legionaires bacteria. My Bradford uses the Honeywell thermostat. I also do not have a mixing valve at the hot water heater.
I have the thermostat set at the "hot" mark which I is supposed to be 120 degrees (per the manual). I used to have it just shy of the "A" setting but my wife and I felt the water was too hot and we were worried about getting scalded, so i dialed it back. But now I'm thinking I could be setting us up for a problem.
My tank does have a circulation loop to my master bathroom which is gravity fed, no pump, and it works. We have instant hot water in the master all the time.
So.....how real is this bacteria threat in hot water heaters? I hear about this on the news but it always seems to be in cooling towers of high rise buildings. I'm almost 50 years old and I have never had a hot water heater set up with a mixing valve.....honestly it sounds like it should be mandatory.
Thoughts?? Thank you, George