View Full Version : Legionella and A/C Equipment.

23-02-2012, 05:11 PM
First of all may I appologise to all our guys that work frequently on A/C units.

Because until yesterday when talking to a customer at a food production factory.
I did not realise that the required maintenance routines had anything to do with Legionella.
Being predominantly Chiller and Industrial I had assumed it was only an issue on equipment outside, which had the ability to provide the heat and airborne water droplets.
I.E. Evaporative cooling towers.
How nieve I was.
Logically when you think about it a evaporator (Indoors) on a heat-pump now acts in heating as a condenser.
Therefore it can create the conditions required to create Legionella, granted there is not normally any vapour present.

But imagine if said evap is left to fester and air flows become restricted.
Is that not the perfect conditions?

So now anyone savvy enough can quote F.Gas for leak checks and Hygiene (cleaning)
To eliminate the conditions needed for Legionella growth.

Possibilities for marketing there guys!

Or at least justifying maintenance schedules.

23-02-2012, 11:08 PM
I know Grizzly, we breath in all sorts of muck in this trade don't we?

24-02-2012, 12:32 AM
I have never heard of legionella in connection with outdoor resi or commercial condensers. With heat pumps and especially solar the big thing is to keep the DHW tank temp above 60c at least once a day for some period of time (don't know what the rules are over there, but it has to be hot enough to kill the bacteria). If there is an issue, it is news to me.

24-02-2012, 02:07 AM
H Grizzly,
I specifically exclude water treatment and testing in all maintenance contracts, mainly because it is totally foreign technowlegy to me, and there are companies out that manage the whole process. Here there is a tight regime of water quality testing which includes swob tests for legionella. I have enough problems with the refigeration side of things.
Unfortuntatly the legionella thingo is all around us and concentrates under certain conditions, then leaps out and kills someone. Chlorine is a good sanitizer, but a big bad boy these days. [Who mentioned chlorine].
I have been installing ozone sanitizers lately particually on ice makers, the forgotten food.

24-02-2012, 07:00 AM
I know Grizzly, we breath in all sorts of muck in this trade don't we?

Don't you mean swallow a lot of crap Brian?

I have never heard of Legionella in connection with outdoor resi or commercial condensers. have never heard of Legionella in connection with outdoor resi or commercial condensers.

True Mike.
BUT these condensers have moved inside the building and now can alternate between being a condenser and evaporator. When considering the usage of a Heat-pump.
Or at least that's how it was explained to me by my customer re A/C and their food producing factory.

Hi Magoo.
I agree with your comments but it would seem the scare brigade have found another "potential Hazard area!
They just may have a point though, If a maintenance regime is all that is needed to satisfy , "who am I to argue?"

I have been installing ozone sanitizers lately particularly on ice makers, the forgotten food.

I have previously read with interest the comments about these from our commercial guys.
To the point that I tell my family not to take Ice with their drinks when out.
Cheers all Grizzly

24-02-2012, 05:49 PM
Bear in mind that when being used in the heating mode the coil would probably have been dry before any heat is added so there is little for the bugs to grow on.

Their ideal temperature IIRC is around 20C.

25-02-2012, 11:09 PM
Research here from several cases indicates that the effected cooling tower or evap condenser could be miles away, due to wind drift from effected system, from factories or high rise buildings. Bit of an unlucky dip where it strikes. Could be another building, factory or household, or you driving down the road. Starts off as flu type symptons and rapidly turns to lunge infections.

25-02-2012, 11:26 PM
Prevention is better than cure but this link may be helpful, should someone become infected.http://www.google.com.au/url?sa=t&rct=j&q=mms&source=web&cd=8&ved=0CHUQFjAH&url=http%3A%2F%2Floveforlife.com.au%2Fcontent%2F08%2F03%2F14%2Fmms-most-effective-pathogen-killer-known-man-mineral-supplement-may-seem-miracle-o-0&ei=V2xJT9-yIePMmAWtlpWtDg&usg=AFQjCNFd3llRnF_Sc2tMQedDXA0-kdXWZQ

26-02-2012, 02:58 AM
Hello Magoo,
What brands of ozone sanitizers would you recommend?