# Legionella controls



## wyrickmech (Mar 16, 2013)

Have a building with 4 water heater systems that need legionella bacteria control. Problem begins with it being a older building and has been in service for 45 years. Biocide film is in the pipe like any other building. The conclusion is which way to protect. Elevate the temp and temper at the faucets or temper at the heater and chemical treat the biocides. The tempering valves would be 1 21/2 and 3 3inch. If i go the other way it would be around 500 sinks.


----------



## ace4548 (Feb 10, 2015)

Probably depends how much the owner wants to spend. I would think tempering at the faucets would be the best solution for preventing Legionella. The other way, you can temper after the heater and as long as you have enough circulation you should be fine also. Just not sure how well biocides work, or how much flushing or how bad it is on pipes. Never used it


----------



## The Dane (Feb 19, 2015)

I would think that the best way is to treat with biocide first as to get rid of the bacteria and then temper at the water heater. That way the water is hot enough to kill all legionella in the waterheater and if all legionella is dead and gone at the source then no legionella should grow in the pipes. I'm no expert so I might be completely wrong. This way you you don't get another 500 points for potential leaks.

Sent from my R1 HD using Tapatalk


----------



## wyrickmech (Mar 16, 2013)

Sorry misquoted it is biofilms and is treated with heat or forms of biocides. After research the only way i have found to treat effectivly is elevated temperature's throughout the system. 140 all the way to the faucets. Any other ideas would be welcome.


----------



## Plumbus (Aug 4, 2008)

D-9 the building and start all over.
Better yet, hire a demo expert and implode the sucker.


----------



## indyjim (Apr 29, 2017)

Can you just chlorinate the system?


Sent from my iPhone using Tapatalk


----------



## GAN (Jul 10, 2012)

OSHA's suggestions.

https://www.osha.gov/dts/osta/otm/legionnaires/hotwater.html#treatment


----------

