Why do split ACs make me sneeze?

August 10, 2008 7:08 PM

Why does using the AC make me sneeze?

I have a split AC (kind of like this picture), and it always make me sneeze when I use it! At first I thought it was just dusty, but I have cleaned it exhaustively and even replaced the filters, but to no avail. Also, I've noticed the same thing with other people's AC's, sometimes.

In Japan people always say don't sleep with the AC on (everybody here uses this type in their homes), and for what it's worth, I never had a problem with normal central AC back in the US.

I know there's gotta be an HVAC allergy specialist out there somewhere, so help me figure this on out! It's really hot here, so I don't think I can live without the AC, but this sneezing is slowly killing me!

posted by phaedrus441 to health & fitness (11 comments total)

Even if the AC itself is clean the wind it creates could be kicking up dust in your house that makes you sneeze.
posted by Jahaza at 7:34 PM on August 10, 2008

Many, many units have mold in the ductwork. That may be your problem.
posted by notsnot at 7:37 PM on August 10, 2008

Check out this story about reasons for sneezes other than allergies and the common cold. Among them are sudden cold drafts.
posted by beagle at 7:38 PM on August 10, 2008

@notsnot: Anyway to check for mold? I know I could pay someone to clean the whole unit, but it's over 100 bucks, so I'm not keen on it unless I know I need to.
posted by phaedrus441 at 7:45 PM on August 10, 2008

i'd wager the japan advice relates to korean fan death.
posted by kickback at 7:56 PM on August 10, 2008

My Japanese wife never let us sleep with the AC on, even when it was as hot as flaming hell out. The explanation is (and I believe it), AC air is very dry, and it makes it easier to catch colds (cold, dry air can damage the lining of your throat, making it easier for viruses to set up shop, which is one of the reasons why people tend to get colds more in the winter). Also, the dust in an AC filter tends to gather dust, fast, no matter how often you clean it, and this dust can harbour viruses, etc.

I sneeze when I have the car AC on. I think it's just because the air is cold and dry.
posted by KokuRyu at 8:37 PM on August 10, 2008

Sleeping with the A/C on makes me stuffy. It also plays havoc with my circulation (thanks, Reynauds) so I only use it if I absolutely have to -- ceiling fan is preferred.

As for why, I've never gotten a good answer (or even much acknowledgment) from any medical professional, including an allergist. Plenty of anecdotal sympathy, though!

It helps me if the A/C is on a moderate, rather than COLD setting, and if it's directed so that it's not blowing right on me.
posted by desuetude at 10:20 PM on August 10, 2008

A/C dries the air, which in turn allows for dust--and therefore bacteria--to fly around a lot easier. I live in a very hot place in the summer, and I only reluctantly use A/C, it's just not good for you.
posted by zardoz at 10:54 PM on August 10, 2008

This happens to my dad and I. Something about mold and mites tickling our noses.

Also, it just might be too cold.
posted by divabat at 11:53 PM on August 10, 2008

You're more likely to be sitting directly in the line of fire with one of these high wall-mounted evaporators than you would be with a ducted unit, which means you're sitting right in a stream of very well-dried air. Very dry air will suck moisture from your nasal passages very quickly, which irritates them.

Try hanging a clean, damp towel in the airstream from the AC and see if that eases the sneezes. As a bonus, moisture evaporating from the towel will help cool the room.
posted by flabdablet at 2:51 AM on August 11, 2008

In Japan people always say don't sleep with the AC on

Gah, this drives me nuts, nuts, NUTS. I could just scream from all the times I hear
"oh, you sneezed, is the air-con too strong?"
"you sound sick; did you leave the air-con on last night?"
"you're stuffed up again? it must be from the changing temperatures - so hot outside and cold inside all the time."

It's called ALLERGIES and all of you people suffer from them TOO (really, in Japan, they're a national past-time). Usually, it is indeed the mold/mite death-combo, but the dry air can be a pain. For the dry air, I used to leave trays of water either under or inside the front of the AC.

how's your break going? we should meet up again sometime. i bicycled out to narita a couple weeks ago - think you could make it up here? ;-)
posted by whatzit at 5:33 AM on August 11, 2008