My AC condensation pipe/pipes have been leaking since I bought my townhouse about 4 years ago right after it was built.
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-there are 4 homes in our single level unit
-my AC is in my attic
-outdoors, there are 4 pvc pipes 3 are about 1" in diameter and the other is about 2" in diameter
-they come out of the wall right behind the AC unit
-they exit maybe about a foot from the ground
-they all have an elbow?/joint? that leads toward the ground leaving about 4"-6" clearance.
-I have so much drainage; enough to make the back of the AC unit sink a couple of inches, and soak the foundation enough to make a section of carpet in the room behind the outside unit wet;

** Why are there 4 pipes dripping on the outside of my house?
**Could these other pipes be from the homes?
**What can I do about this problem/dripping?

The outside pipes are the answers.
the one inche pipes are the condensate drains. One for each unit. The last 2" pipe is the overflow pipe for the washer dryer pan located in each unit connected togeather or a sump pump pipe.
Check to see if the large one drips, It should not be doing this unless they brought the ac drain into the pipe somewhere. Which they should not have done.

As far as the condensate draining behind the outdoor units, This is done all the time. While the dripping of the water may have assisted the settlement of the soil under the AC unit. That is not the primary cause. Its natural settlement of the soil that is occuring. Quite often when they dig a foundation they do not properly backfill once the basement is built. This loose soil eventually settles and requires replacement. You simply need to lift the edge of the cement that supports the unit and shovel some soil under it.

As far as the water coming into the basement causing the carpet to get wet.
This can be caused by two factors.
Either a failed outdoor water proofing system if it exists at all.

OR the 4th missing 1 inch condensate pipe is dripping within the wall cavity and running down inside the block wall or behind the finished wall if there is one. It should have been run to the outside like the rest of them. It could have been pushed back into the wall when they did the siding. Or the contractor goofed and forgot to put the pipe on the end of the drain to bring it outside past the finished wall. If the basement is finished you may need to cut a hole in the ceiling in the area of where the pipes go to the outside of the unit and check there.

My bet its the pipe missing. Condo and townhouse construction is done as fast as possible. The ac subs that work on these units get paid very little to do the job. If they did not have the fitting necessary to run the pipe outside the wall they simply move on and forget about it. It cost them to much money to go back and do it right.

I would go to the assocation and ask them to fix this. My bigger concern is how long the water was dripping behind the finished wall? Again assuming I am right this condition can cause mold to develop only in a few days. Once it starts it does not take a lot of moisture to keep it growing. Get it checked out soon.
Keep us posted on what you find out.

Thank you so much for the prompt reply! I just have a few more questions.

****By the way I don't have a basement, it's just a single level unit with 4 connected townhomes. Each home as far as I know, has a small attic space that houses the water heater and the AC unit with a small space for storage.****

QUESTIONS:

Is it legal to have other peoples AC condensation draining onto my personal property and damaging it?

If not what can I do about it?

Who should I go to about the damage to
my backyard and my home?

For all of this should I go to the association like you mentioned before?

Should I try to get in touch with the builder/contractor of the subdivision are they still responsible?

It is very common on multi property homes to have pipes and utilties run through and out of homes in common areas such as yours.

I assume the assocation is responsible for the exterior and all common areas. If you read your deed and bi-laws it will state what these common areas are. Typcially its the interior of the walls, behind your inside finished walls towards the outside of the building. But you need to read these first before passing this judgement.

I would go to the assocation/management company with a phone call and follow up letter explaining the issues your haveing. Explain that your suffering from water and property damage that could effect your health and cause a safety issue on the outside due to settlement (if its that bad) and that if they do not correct this in a timely fashion you will hold them responsible for any additional damages or ill health effects that occur. Be polite about it, as you will have plenty of time later to yell and scream.

Remember they do not know this is happening. They should respond quite quickly. But you need to do this with a certified letter so you have a record of this action.

If they do not respond within 24 hours weekdays, you then need to contact them once again with formal letter and phone call and find out why they have not responded to your emergency request. It is critical that you document when and who you speak to during every contact. As this may come in handy if you end up using the legal system to get them to fix your issues.

Do not bother with the builder. Unless you paid them directly they will not respond to you.

Now comes the trickey part. You will be responsible for the damaage to your finishes, carpet etc. Normally the assocation will replace walls, framing, or make any repairs in order to prevent any additiional damage to your unit. Your responsible for any water damage that occurs. Which is why you have insurance. Be sure to take pictures, or better yet contact your insurance agent as they need to be involved. They are not responsible for what caused the issue, only to replace your damaged carpet. If you mention MOLD, you most likely will not get any coverage as most insurance companies have sent out disclaimers to that effect.
Good luck!