Biocide for a/c units

Could you make the drain larger so that it is less likely to plug up? It would take a serious dust rat to plug a two inch hole.

BobH

Reply to
BobH
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My shop is heated and cooled by a 18000BTU window unit mounted high on an exterior wall. I have a reoccurring problem of the condensate drain plugging with dirt, algae or whatever slimy crap that forms in the unit. When it plugs the water drains down a sheetrock wall into my shop. This may go on for a few days because I am unable to check it on a daily basis. I am looking for something I can periodically add to the pan to try to keep this problem at bay. I realize that anything caustic/acid will likely do more damage than good to the coils. Any of you ever fight this problem? I live in the very humid deep south and keeping the humidity down in my shop requires the a/c to run around the clock so I just can't shut things down and walk away for a week at a time. My a/c guy says all the commercially available solutions eat the coils up but I know he'd like to make a service call every few months to clean things out so I wonder if he is completely honest with me. Any ideas would be appreciated.

Reply to
Gerry

Can you make it a regular maintenance practice to clear the drain? I.e., every morning, or every Monday, or whatever, run a swab/wire/drill/reamer up the tube, and make sure you're seeing flow?

(Note: this is really cool advice, and I would _never_ be able to take it because I'm such an airhead -- every Wednesday night that I remember to get the garbage to the curb is a victory).

Reply to
Tim Wescott

Bleach sanitizer solution, mixed per the directions on the bottle and poured into the condensate pan, *not* on the coils. Do this once a month if you can and you should have no issues. Heck, fill a 5 gal bucket with the solution and rig a cheap fountain pump on a digital timer to pump the solution into the condensate tray once a week for 5 minutes.

Reply to
Pete C.

An AC supply like Johnstone has pellets that you can put in the condensate tray. I don't think they eat the coils up.

Reply to
ATP

The problem is that the channel that the condensate flows through is not accessible. Water builds up in front of the evap coil then overflows into the shop wall. The condensate does not make it to the drain hole. No way to access it directly without removing the whole monster unit from the hole in the wall.. The drain channel, that runs under the evap coil is stamped in the pan so no mods can be made. The manufacturer insulated under the evap coil with styrofoam and silicone and both of these overflowed into the drain channel originally. The bottom of the evap coil sets in a channel and therefore stands in condensate so anything corrosive will likely eat the coils over time. It's pretty poor design in my opinion

Reply to
Gerry

If you are talking about a unit with an exhaust fan that blows out through a radiator, water should flow into that splasher area and evaporate on the coils. If you are having an excessive flow out the drain tube, the waterway to the splasher area might be clogged with silt. If the drain tube is clogged, the waterway to the splasher area might be clogged too. If the splasher is working properly, keeping your air conditioner running efficiently, there might be little or no water draining out the tube.

Make sure that you can hear the splasher. Otherwise, it needs cleaning. You can do it yourself with a water spray hose. Spray through the back of the unit to clean the radiator, and spray out the bottom area. I would spray downwards against the front radiator too, to remove lint. Cover the electronics and make sure they dry out before replacing the cover. Yes, that assumes you can get to and remove/replace the unit.

Reply to
John Doe

Gerry fired this volley in news:ea2d686d-eb15-46e2- snipped-for-privacy@l20g2000yqm.googlegroups.com:

This immediately tells me it's not the unit at fault OR the need for a biocide, but the installation of the unit.

A wall/window unit should _never_ have the evap sitting in condensate, because if it's installed correctly, there's no possible way for it to pool there. It should (if anywhere) pool under the condensor coil and/or condensor fan/slinger ring.

You need to _slightly_ re-mount that unit so there's about 5 degrees of slope away from the inside downward toward the outside.

THEN clean the tray with sanitizer, wash it out with a sharp stream of water from a hose (yes, I know things will get wet), and have problems no more.

I, too, live in the deep, humid, hot south. No such problems here. If the condensate is allowed to run, rather than pool, it never will have a chance to grow enough crud to block it up.

Once every two or so years, I wash my bottom pans out (have four such units around the office, barn, and shop), but that's to get rid of mud- dauber mud that has accumulated, not algae.

LLoyd

Reply to
Lloyd E. Sponenburgh

The problem is this crap comes out of the air in the shop. The evaporator coils get wet, and any dust, etc. in the air sticks and is washed down into the drain with the condensate. A perfect growing medium for all sorts of microbes. if you don;t have a filter on the air handler, put one in. Also, if you can adjust piping so water doesn't sit in low spots, that may help.

Jon

Reply to
Jon Elson

Oh, window unit! Yes, the filter is probably no good, you can get better ones at the hardware store. Then you'll have to clean the filter periodically, but that should be much more accessible than the drain passages.

Jon

Reply to
Jon Elson

Most window and wall units. The condensate from the evaporator (cold) coils. Goes to the back of the unit, and is "slung" onto the condensor (hot) coils. The theory being that the water evaporates on the hot coils, and helps carry off heat. I don't think it does much good, where I live.

The two AC units I've got. I've got the condensate routed out of the units without being slung onto the condensor.

Perhaps you can rework your unit, so the condensate runs outdoors, through a tube.

As a cheap alternative, if the problem really is biological. You can pour some clorox and water into the evaporator coils in front, and that will drain its way back. Of course, it makes the room smell like clorox for a while.

Reply to
Stormin Mormon

I've sprayed bleach water on the coils, with no aparent damage.

Reply to
Stormin Mormon

Very observant. Good job, Lloyd. I mean, LLoyd.

Reply to
Stormin Mormon

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