So I just moved into a new house in NC that I am renting. The house has central A/C which is great, but because there is no basement so there is no basement drain. So the A/C expels the water into the backyard. The place where the water is expelled from the A/C creates small stagnant pool of water which is making for a heck of a mosquito problem. I could fill in the hole, spread the water out, and that will be fine in the short term. This issue will continue unless I can think of a solution. The hose that expels the water is near to the ground, so a sizable rain barrel seems out of the question. You'll want to create a small leach pit, which will allow the water to drain into the ground. Start by digging a hole about 12-18" deep (depending on your soil), Next fill the bottom of the hole (about half the hole) with crushed stone (loosely compacted). Fill the rest of the hole to about 1" from the top with sand, then finish with a nice decorative stone. If the soil is typically very moist (i.e. you get a lot of rain), you can skip the sand and fill the hole all the way up with crushed stone, and then top with decorative stone.

Another option would be to top the hole off with something like this So you'll follow the same procedure as above, but rather than filling the second half of the hole with sand/stone you'll put in a drain pipe like this. The whole idea here is to have the water leach into the ground, without forming a puddle where mosquitoes and other things can breed. If you do this and still find that the water is pooling, you'll have to take more drastic steps. The best option from there would be to install a French Drain, and connect the drain line from the AC unit to it. There are already some questions that deal with french drains, so if it comes to that you should have no trouble finding out how to do it (how do i build a french drain). You could also buy a small leach pit, but this might be overkill for your situation. You'll bury this in the ground surrounded by 3/4" - 1 1/2" crushed stone, then connect the AC unit drain to the lower inlet pipe (the upper pipe is a vent).

Before you drop it in the hole, remember to remove the small hole knockouts (to allow leaching). This will require a larger hole, and again may be over kill for your situation. Where the line comes out of the AC unit, there should be a trap like you'd have under your sink, and a removable cap above the trap. Open the cap, and put a little bleach in there. That should kill whatever is growing and hopefully avoid any mosquito issues. You'll want to do this periodically to keep the line from blocking anyway. How often depends on your area. I do it yearly, but the trap drains indoors. I've heard others do it every month. No need to dump the whole bottle in, my goal is to fill the trap without losing too much bleach down the drain. Edit: For those paranoid about bleach going outside, hot water and vinegar is an option, but I'd up the quantity to several cups to really flush the line. Just keep in mind that if you don't keep this trap clean, then anything growing in moisture outside will eventually be growing inside, clogging the trap, or worse.

The story I heard was someone that foolishly ran the drain into their septic system, some deadly bacteria ran back up the line, into the home, and killed the home owner in a period of months. Given the choice, I'll go for the 1/4 cup of bleach.much does outside ac unit cost Finally, for the hole caused by the drain outside, fill it with sand and cover with gravel. my ac window unit wont turn onI don't think the mosquitoes will go digging to get to the water.american standard ac package unit Bleach can damage your pvc pipes and apple cider vinegar will attract fruit flies. Stick with white vinegar only to clean out your ac condensation drain pipes. Pour in a cup or two of white vinegar, let it sit for 5 min., then pour in a gallon or two of hot tap water - this should clean out your drain pipes safely.

Still might kill plants near the drain exit.Browse other questions tagged water central-air mosquitoes or ask your own question.Air Conditioner Condensate Problems - It is important for air conditioning preventive maintenance to be performed on your system to avoid problems. Condensation water leaking near the air handling unit can be avoided with proper air conditioning repair and preventive maintenance. Normally this is a very simple problem that can be fixed in less than 30 minutes. Here is a list of what can cause water around the outside of the air conditioning air handler unit. Air Conditioner Condensate Problems - Possible CausesThe black insulation (called Rubatex) has a tear in it or doesn’t cover the entire suction line. This line normally (in Air Conditioning air condition mode) operates below the dew point and will sweat if it is not insulated. It must have a sealed vapor barrier to be effective.Nu-Calgon 4296-60 Pan-Treat Scum 200 Tablets to prevent drain clogs for condensate pans available hereCondensation Drain PluggedThe insulation surrounding the air handler supply transition or ductwork is torn.

The supply transition and duct can operate (under the right conditions) below the dew point and sweat. It is important that the transition have a vapor barrier around it. This scenario is especially true for those that have over sized units.The condensation drain line is plugged. Air handling units in attics should have a secondary condensation pan in case the primary condensation pan overflows. Occasionally, the secondary condensation pan will also clog and not drain. Water builds up in the ceiling and eventually there will be a drip if the homeowner is lucky. If no drip, then eventually the entire ceiling will fall. In the attic, I always recommend a float switch installed in the secondary air conditioning condensation drain pan. If the secondary condensation pan fills, the float switch will rise and cut the whole air conditioning unit off. This will force the homeowner to look for a problem or call an HVAC technician. In this case, with the float switch, the problem can be rectified before water damage occurs.

Algae or a foreign obstruction such as mulch or potting soil can plug condensation drain lines. These air conditioning condensation drain lines (either black plastic or white plastic looking pipes) usually drain out somewhere at the base of the house into a flower garden. Make sure mulch or soil doesn’t plug these condensation lines up. Adding algae treatment to the lines or pans can prevent algae. Some people pour bleach in the evaporator condensation pans once a year. Whatever the way you use to prevent it from growing in your evaporator condensation pan, know that if steps aren’t taken to prevent algae growth, it will eventually plug the condensation lines.If the air filter is extremely clogged, a duct is collapsed, the evaporator coils are plugged with dirt or dust because no air filter was kept in the system, or there is a low charge of Freon, the evaporator coil will freeze. When it thaws, it will overwhelm the evaporator condensation pan and leak outside the air handling unit.

Some evaporator condensation pans are made of metal and can rust through over the years of use. In certain cases, the entire air handling unit must be changed out. In other cases, the evaporator coils and evaporator condensation pan must be changed. Normally if the air handler unit is old enough to have a rusted evaporator condensation pan that leaks, it is time to change the air handling unit.Unit or Drain Pan Slope. If the evaporator drain pan is not sloped toward the drain the water will not drain from the evaporator pan properly. Additionally, the condensation drain piping must be sloped.Related Link: See what a clogged drain for an air conditioner can do to cause water damage to your home. (opens in a new window) Insulation ProblemIn either case the condensation drain or any other thing that can cause a condensation leak should be repaired as it will cause water damage to wood and mold and mildew issues that can affect health. Moisture dripping into insulation also derates the insulation R-value so the insulation is not as effective.

Air Conditioner Condensate Problems - ConclusionIf your condensation drain got clogged or plugged or something caused the drain pan to overflow and the insulation got wet including the insulation on the duct work this insulation needs to be replaced. The insulation for the house in the attic or other place will not insulate as it did before it got wet. Additionally, the insulation surrounding the duct work needs to have air tight integrity and a good moisture barrier. If it does not have a moisture barrier and humid moist air penetrates the insulation to the duct work then the duct work will begin to sweat.The excess moisture will eventually drip into the insulation surrounding the duct work and before long it begins to sag and this separates the insulation at the seams and causes more moist air to reach the duct work creating a larger moisture issue. Eventually, the insulation will fall off the duct work and all the water will cause water damage. Seal that duct work insulation to prevent this from happening.