RV AC Water Runoff: Why Is My RV AC Dripping Water Outside?

This is not always a problem. When you notice that your RV AC unit is leaking water, this may be a normal function. It takes place on cars and trucks every time you use the AC unit. AC units help remove excess moisture from the air but that water has to go somewhere.

This is a normal situation and all the air conditioner is doing is releasing condensation back into the environment. However, if the water is running or dripping where it shouldn’t, then you may have a leak, a blockage, or some other problem.

To learn more about this issue, just continue to read our article. It is filled with the information you want to know about so you can relax or be spurred to look for the source of the leak. This situation is not always a fix waiting to happen

Why is My RV AC Dripping Water Outside?


The first thing you need to do is to determine if this is a leak or normal operation. It is easy to confuse the two and if you make a mistake, you may waste some money and time repairing something that should not be repaired.

When you turn the AC unit on, the air conditioner pulls the humidity out of the air. Then it may drop that excess moisture into a drip pan. But the drip pan is not going to hold all the water the AC unit puts in it.

That is why the drip pan may have a hole in it or a hose leading to the roof of your RV. From there the water from the drip pan leaks out onto your RV’s roof and harmlessly rolls to the edge of the roof and down the exterior wall.

This system only becomes a problem when there is a clog or something wrong with your AC unit. If you are concerned about the amount of water, that volume will depend on what type of day it is outside.

You will not see a lot of water if the days have been dry and there is no humidity in the air. You will see a lot if the reverse is true or if those hot days came with a lot of humidity.

Water Runoff From RV AC Roof

Generally, and as we just said, this is a very normal action on the part of your AC unit. It is its job not only to cool the air inside the RV but to also remove any excess moisture in the air.

Once it has removed the excess moisture, it has to get rid of it. There are no storage tanks in any air conditioner where this excess moisture can go. If the AC unit hangs onto the moisture, then there is potential for that moisture to damage the AC unit.

So the water or condensation has to go. The process used to accomplish this has been noted in the previous section. There is one way to tell if the water you are seeing on your RV walls is the result of normal activity or if there is a problem.

These water drips are normally on the outside of your RV. But if you see these water drips where they are not supposed to be, then you know there is a problem with this moisture drainage system.

Once you see this new route the water is taking, you can either do the fix yourself or call in an experienced technician who has all the right tools and knowledge to handle the problem.

Of course, the source of the problem is simple so save the money and do the fix yourself.

Why is My RV AC Dripping Water Inside?


There are a limited number of sources for this problem. The first problem, which may be rare, is that the hose that directs the water is damaged, plugged, or has a hole in it.

Replacing the hose, if there is one, is the only real repair that you can do. Duct tape will work but you will have to replace that hose eventually. The other source for this problem is that the drain holes have been plugged by debris.

That debris can be leaves, dirt, or whatever has gotten onto your roof. If the holes are plugged, then you have to go up and unplug them. A third source for this problem is that the bolts holding your AC unit got loose or the sealant cracked, etc.

The water could come inside at that point. This means you have to either replace the gaskets between the bolts and the roof or use sealant to stop the leaking.

Those are the areas you have to check when you see water dripping inside your RV. The repairs are simple and can be quick if you know what you are doing and are not afraid to climb up onto your roof.

This is not going to be an inside repair job. You have to go outside to solve this problem.

Is RV AC Supposed To Drip Water?

Yes, it is. If you have ever looked under your car or pick-up truck after using the AC unit in those vehicles, you may see a pool of water underneath. In some cases, owners think they have a leak in the engine when it is just the AC unit depositing the condensation onto the ground.

The water taken out of the air inside of your RV is not deposited in the same location as a car or truck’s AC unit will do. It will simply release the moisture onto the roof and let the curvature of the roof move the water to the side.

At that point, the water will simply drip down the side and leave a pool of water somewhere next to your RV or trailer. This is all normal and when you see this pool or puddle of water next to your RV, you know your AC unit is working normally.

What isn’t normal is when you see that your interior walls, carpet, or counter soaked with moisture. When you see this situation, you know there is a problem on your roof and you need to go up and fix it.

Then, yes, it is normal because the AC unit has to dispense of the moisture it took out of the air. It cannot hold on to it or it risks being damaged itself.

How Do You Deal With AC Runoff?


This is very simple and the solutions are not that hard to apply. The first thing you do when you see the excess moisture running down the side of your RV is NOTHING. Unless you have a water leak on your roof, this is a normal situation that requires no action on your part.

Now if you see the water dripping on the inside of your RV, you have to do some investigative work. Not only do you have to find the reason why the water has been diverted but you also have to find the source that let the water inside your RV in the first place.

After that, you have to repair both issues so the water can drain like it should. The repairs usually call for cleaning out any clogs and putting sealant over the area that the water used to get inside.

It only takes a few minutes to do these repairs and what takes the longest time in this task is finding that leak in the roof. That can be just about anywhere that draining water can reach.

Make sure to have the right sealant and tools with you so you do not have to climb up and down the ladder multiple times.

RV AC Not Draining

This is a big problem. If you do not see the water running down the side of your RV or coming inside through your ceiling or vents, then you know you have a bigger problem.

The drain pan is holding all that excess moisture and could release it in the wrong way at any time. This situation calls for an immediate fix and you may have to remove the AC unit to get to the drain pan. It is usually located on the bottom of the air conditioner.

Of course, you have to go up and inspect the drain pan to see why it is not letting the water out. Usually, it is debris that is blocking the drain holes. There are other sources than debris blocking the drain pan. Here are a few possible sources that create the same situation:

1. The air conditioner was not installed properly- it may be off balance or tilting to one side. This will keep the water from using the drain holes. Re-installation will be your only solution.

2. Freezing and thawing damaged the drainage system- this may be rare but it can happen. Make sure your air conditioner has adequate airflow to stop any freezing.

3. Excessive humidity- this will create too much moisture and you may see some of it drain inside your RV instead of outside. There is just too much water for the drain pan to drain normally, sending the water out some other avenue.

4. Damage to the drain pan- this can happen due to the many bumps your RV takes as you drive. Or the vibrations of the road cracked drain pan giving the water a second exit point. This second exit point can allow the water to leak inside your RV.

5. Seals are cracked, etc.- the sources for this problem are the same as immediately above. Sealant is known to crack or chip from time to time letting water get in the holes.

How do You Unclog An RV AC Drain?


This is not a complicated task to perform. It is a matter of bringing the right tools to the roof with you. Part of those right tools include a screwdriver or two to remove the AC unit.

Once that is off, you can use either a shop vacuum to suck the clog out of the drain line or a piece of wire, pipe cleaner, or even a small screwdriver to get the clog out.

The key is to make sure you have turned all power to the AC unit off. The last thing you need is to have a shocking experience while on the roof of your RV or trailer.

The solution you use is up to you and the one that will work the best. It all depends on where the clog is and how hard it is to remove.

AC Water Drain Tips

1. Once you have removed the clog, pour some bleach down the drain to help kill off any mold or mildew that may have started to form and grow.

2. It is often not the drain that is the source of the interior dripping water problem. Sometimes the evaporator coils get dirt or debris stopping it from working right.

In this case, you would have to clean those coils as dirty ones help divert water or moisture to the wrong spot creating the leak. This option is a little more labor-intensive than unclogging the drain.

3. When you are done cleaning the drain, do a test to make sure the water will drain smoothly and easily. If the water doesn’t do that, then you have not removed all of the clog. Keep cleaning till the water drains properly.

Some Additional Words

When you see water dripping down the side of your RV and coming from the air conditioner, then all is well. This is normal and you should not have to do anything to change what is going on.

The time to worry and take action is when you see the water dripping inside your RV. When you see that you know the drain is clogged and you have a roof leak somewhere.

Do not delay in repairing this problem as the leaking water will only make matters worse if you let it continue.

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