Bad smell from a/c units - hazardous waste?

[alexdouglas1969]

There seems to be a difference of opinion what causes the bacterial growth on indoor units. I have heard that it's cosmetics, aftershave, 'bad air', condensate and more recently - HUMAN SKIN !! Maybe all of the above!

I would be interested to know what everyone thinks causes this delightful phenomena.

On the subject of the SKIN THING does anyone follow any hazardous waste regulations with safe disposal / sterilisation etc... surely a filter clogged up with rotting skin is officially classed as such?

Have a nice day.

[chillin out]

On the subject of the SKIN THING does anyone follow any hazardous waste regulations with safe disposal / sterilisation etc... surely a filter clogged up with rotting skin is officially classed as such?

Have a nice day.

You could say the same thing about your vacuum cleaner, most of it's contents is dead skin.


Chillin

[hendrag]

the cats pee smell is caused by a mould growing on the coil, i think it is caused by the moisture lingering on the coil when the unit is switched off. Melco did a load of work on this in the 90s give them a call. To get rid of this smell there are loads of overpriced coil cleaners which have various levels of success. Ive always used dettox get it from tesco for a couple of quid. Its easy to use cheap and increadibly effective + it doesnt smell of anything

good luck

regards

[nh3simman]

I installed 100 cassettes at a temporary casino. After a few months, the maintenance manager told me that there was a green slime in the drain pipes. I took a sample and we found high legionella spore count.

I treated with chlorine in the drain pans but I would like to know how legionella grows on a 7degC chilled water coil!

I was told that human skin and smoke was the cause of the problem.

[Brian_UK]

Yep, human skin is the main culprit.

One of those useless bits of information that is actually a 'useful' bit for us is that we, yes even we do it, change our skin layers on average once a month.

All those skin cells then drift through the air and get sucked up by that nice clean a/c filter.

edit: Yes, you should really use a face mask whenever you are changing/cleaning filters.

[momo]

The muck in A/C units is no joke: plenty of airborne food + virus (live and fragmented), fungi (live and spores), bacteria... if the unit is dry (filters) use a dust mask at least - I am against blowing out condenser/evaporators with power fans (usual way over here - results in a cloud of biological warfare dust), a good wash with proper condenser cleaner fluid and water is best. (Avoid those small containers of cleaner - expensive - and the scented ones - they eventually break down or become unbearably strong and annoying). Dettox I prefere for sore feet and cuts, too much general use - like with antibiotics leads to more resistant bugs.
Even a graze with the fins of an evaporator can lead to a a localized infection, and the human body is not designed too well to deal with fungi entering the bloodstream. There are quite a few US studies worth chasing up on this topic. Therefore at least vinyl or rubber gloves and care when handling those parts.

The fun is justifying the cost and risks to customers when dealing with a full strip and clean job !!!

[nh3simman]

Reading your comments about the gunk on air filters makes me feel a but queezy.

I never thought about it before when doing plant maintenance.

[The MG Pony]

I use a full face mask with chem rated cartridges, best investment I EVER made, from welding to cleaning that this has payed for its self a thousand times over! I'd highely recomend any service tech to have one for just that reason as fungi in the eyes isn't too good either!

[chillin out]

So if you can get all this from AC, has anyone really thought about morgues?

We all know the process of refrigeration forms the moisture in the air to condense on the evap causing wetness, but in a sealed room the only moisture in there is from dead folk.

Think about that next time your changing an evap motor in a mortuary.

Chillin

[momo]

Curiously enough straight refrigeration evaporators (8C and lower) seem to be "cleaner", possibly due to higher water flushing from condensate and less ventilation of cooled room leading to less "fluff" (hair, skins, house dust etc), the fins are also more spaced than A/C ones (space and looks are more important in lounges hence more is squeezed into less space.)
About condensate drains, use syphons with drain plugs if going to sewerage, though in areas of water with lime/salts accumulation some plants seem to like A/C drip drip drip (except the above fluffs it is mostly distilled water!)
Careful with condensate tray bug killer tablets they are highly toxic to all forms of life.

[frank]

This makes for interesting reading

http://www.advancedengineering.co.uk...rt.asp?tid=277

[Brian_UK]

Good link Frank, I think I'll get out of A/C right now

I'll have to get all this added to our risk assessment forms otherwise there won't be any excuse for catching the flu now.

[frank]

Hi Brian

I particularly liked this one

Mycotoxins, produced by moulds, toxins and metabolic by products (gaseous emissions) – these have been found to contain a c**ktail of volatile organic compounds (VOC) including dead and dying bacteria thought to be responsible for the “Dirty Socks” or “Tom Cat” smell emitted by some indoor coils


Obviously, the next time I 'Drop One' between the sheets, I can say it was " a gaseous emmission' caused by a 'metabolic by product'

[The MG Pony]

Ahk you should see some of the restaurants evaps! you want "By products" look no further!

[marc5180]

and to think we breathe it in

[The MG Pony]

and eat near them!