Why Is My RV AC Leaking Water Inside? How To Fix

Living in an RV full-time is one of the most freeing adventures. But, now and then, something happens that delivers an unwelcome dose of anxiety. Nothing packs a wallop like noticing that your RV’s air conditioner leaks water inside. So, if you are asking yourself ‘Why is my RV AC leaking water inside?’ You have come to the right place.

Don’t worry, though! I’ve got you covered. In this article, I will walk you through how the RV air conditioner works, why water might be leaking inside, and, most importantly, how to fix it by paying attention to potential issues with the RV AC unit.

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How an RV Air Conditioner Works

An RV AC system uses a refrigerant to cool air passing through its evaporator coils. When the liquid refrigerant converts to a gas, it absorbs the warm air in the RV, turning it into chilled air. A compressor converts the refrigerant back to a liquid and creates unwanted heat. Then, the condenser coils evacuate this unwanted heat to the outdoors.

If you tackle the issue of water leaks, it’s essential to understand how your RV’s air conditioner works. The air conditioner’s cooling process creates condensation. This condensation is collected in the drain pan and drained off your roof.

Water on the Roof is Normal

I am sure you have noticed water dripping off your roof from the outside. If it is humid or your air conditioner runs a lot, you will see more dripping. Increased condensation is entirely normal. Condensation forms on the air conditioner, and the drain pan removes the excess water. 

Water Dripping Inside the RV is NOT Normal

While some moisture on the roof is standard, water leaking inside your RV is not normal for air conditioning. Rain water can also contribute to water leaking inside the RV if the gasket or roof is compromised. Puddles on the floor or wet spots on the ceiling or walls can indicate a few different concerns.

Identifying the cause of these concerns should be done promptly to avoid extensive water damage. Some common issue are:

• A clogged drain line or drain holes
• A damaged mounting gasket
• General roof damage or roof deterioration
• A broken AC shroud
• A leaky evaporator coil
• Improper AC installation

Common Causes of an RV Air Conditioner Dripping Water Inside

Most RV air conditioners have the same components and leak for similar issues. The most common causes of leaks are:

1. Blocked or Restricted Drain Line or Drain Pan

A blocked drain line is the most common culprit behind RV air conditioner leaks. Fortunately, this is often a straightforward fix. Climbing on top of your RV to locate and visually inspect the drain line can reveal any clogs or restrictions caused by dirt or debris. A plugged drain hole is an easy fix.

2. Damaged Mounting Gasket

A damaged or poorly sealed air conditioner gasket can leak water inside. It is essential to inspect your gasket. Replacing a damaged gasket with a new gasket is crucial to prevent leaks.

Always ensure the gasket is free from debris and secured appropriately. Do not overtighten the gasket, as this can cause the gasket to leak.

3. General Roof Damage

If there is damage to your RV roof, it may not be able to drain pooling water effectively. It is essential to inspect your roof material for tears, damage, and any visible signs of damage. Repairing roof damage can prevent water damage. 

4. Broken AC Shroud

The AC shroud protects the air conditioner from the elements. Water can seep into your RV’s interior if the shroud is broken or improperly installed. Inspect the AC shroud and replace a damaged shroud to avoid costly water damage. 

5. Evaporator Coil Issues

Issues with the evaporator coil can contribute to interior water leaks. If the evaporator coil is dirty, it may lead to water accumulation/draining issues. 

Additionally, if your copper lines have corrosion, it may be time to consult a certified RV repair technician. 

6. Improper Installation

If the air conditioner installation is incorrect, it may not be able to collect and drain condensation appropriately. This situation can result in water pooling and leaks inside.

How to Fix an RV AC Leak

Is your RV AC leaking inside? There are three easy steps that you can take to address a leaking RV air conditioner. These easy steps are as follows:

Always disconnect the shoreline and 12 V battery power when working on your RV AC unit.

1. Clear Blocked Drainage Pipe by Using a Wet/Dry Vac

You must climb onto the roof of your RV to assess for a blocked drain. Remove the AC shroud and the evaporator cover to locate the drain pan. Clean any debris from the drain pan and drain pipe using a wet/dry vac.

When inspecting this area, ensure that there are no bends in the line that restrict water flow.

2. Dirty Air Filter Can Lead to Clogged and Restricted Coils

The RV air conditioner should be checked and cleaned for regular RV maintenance. When accessing the AC on the roof, use an approved foaming cleaner and brush to clean the coils.

In addition to the coils, the air filter should also be cleaned or replaced. Cleaning these filters and coils ensures that your AC unit has proper airflow. This maintenance can prevent issues with the evaporator coils. 

3. Ensure the Trailer is Properly Level

Your RV air conditioner relies on proper rig leveling for air conditioner drainage. Always use a level to check and adjust your RV. Keep in mind that some soil and sand can settle over time. This setting can result in a once-level rig becoming un-level.

How to Clean Drip Pan on RV Air Conditioner

Cleaning your RV air conditioner drain pan should be part of your RV maintenance checklist. This easy job can be done by following these steps:

Always disconnect the shoreline and 12 V battery power when working on your RV AC unit.

1. Disconnect the RV shoreline and 12 V battery.
2. Remove the AC shroud.
3. Locate the drain pan.
4. Remove the drain pan.
5. Clean and empty the drain pan.
6. Wash the drain pan thoroughly.
7. Replace the drain pan.
8. Replace the screws and shroud.
9. Return power to the RV.

Video: Why Is My RV AC Leaking Water Inside?

Tips for Maintaining Your RV Air Conditioner Unit

1. Inspect the shroud regularly to ensure it’s intact and properly installed.
2. Clean the air filters at least once every month or more frequently if needed.
3. Clean the condenser coil and evaporator coil to prevent dust and dirt buildup. The frequency of this maintenance depends on usage. It is best to clean the coils at least once or twice a year.
4. Inspect the rubber gasket around the evaporator coils and replace it if it is cracked or worn. Inspect the gasket every time you are cleaning the coils.

RV Air Conditioner Common Problems

• No Cool Air Flow: One of the most common causes of poor cooling for an air conditioner is dirty air filters. If you clean your air filters and still have issues, there could be a refrigerant leak or compressor issue.
• Weak Airflow: Some possible causes are clogged air filters, dirty AC coils, or a faulty AC fan. 
• Weird Noises: Some possible causes of noises coming from your AC are loose components, fan motor issues, or a compressor issue. 
• Bad Smells: The most common cause of odor inside the AC is Mold or mildew. Regularly cleaning the coils and air filters can prevent these issues.
• AC Not Turning On: Some of the most common causes of an AC unit not turning on are a tripped circuit breaker, a faulty thermostat, or a compressor problem.

When Is It Time To Call a Professional?

If you have attempted to troubleshoot your AC unit following the above steps, it may be time to call a certified RV AC technician. Ineffective cooling can cause an increase in utility costs and is better to address sooner than later. 

RV Air Conditioning Unit FAQs

How do you unclog an RV AC drain?

Unclog your RV AC drain using a wet/dry vac to remove any debris blocking the drain line. You can run the vacuum over the drain hole to remove accumulated debris. You can also unplug this drain line and blow it out using an air compressor. A clogged drainpipe is an easy problem to address.

If the drain is difficult to unclog, it may be worth taking the RV to a professional RV shop.

How often should I clean my air conditioner coils?

Cleaning your air conditioner coils is essential to RV maintenance and should be done at least once yearly. If you live in a dusty environment, you may need to clean your AC coils twice annually. Regular maintenance is an essential part of RV living.

If you notice any reduced cooling, inspect and clean your coils.

How do you fix a leaking air conditioner?

Troubleshoot your RV AC leaks by clearing the drain tube and drain pan of debris. Inspect these items and the gasket for damage and debris.

What is the most common cause of water leaking from an RV air conditioner?

A blocked or restricted drain line is the most common cause of water leaking from your RV AC. Debris, leaves, and dirt can obstruct the drain line over time. Regular AC maintenance can prevent water from leaking inside your RV.

Why does my RV AC smell like mildew?

Mold and mildew in the RV AC can lead to odors inside the RV. Cleaning the dirty evaporator coil and drain pan can reduce mold/mildew growth. There are foaming coil cleaners that do this job well. Mix vinegar and water to clean the area with mold/mildew. 

How do I get rid of mold in my RV air conditioner?

Eliminating the mold in an RV air conditioner starts with cleaning the affected area. Remove debris and clean with a mild detergent or vinegar and water.

After this is clean, maintain your AC regularly to keep the area mold/mildew-free. Routine inspections should be done to monitor this to avoid costly repairs.

Should my RV AC run all the time?

RV air conditioners will run for extended periods in hot climates. The AC should be able to operate non-stop if there is a power source. 

How do I stop my air conditioner from running constantly?

You can minimize AC use by adjusting the thermostat, cleaning the air filters, and insulating your RV.

What is the best setting for an RV AC unit?

The ideal setting for your RV AC unit depends on each individual. Set the thermostat to a comfortable, but not excessively cold, setting. Many RVers recommend ensuring the fan runs constantly to reduce stagnant air in the RV.

Dometic Air conditioner Leaking Water Inside

Leakage only occurs when the unit is running.

Inspecting the area around the unit is essential if a unit is only leaking when running. Inspect the framing and roof seam for any damage that compromises the seam.

Find the source of the leak. Inspect the mounting gasket for any tears or debris. If the gasket has damage, replace it. Additionally, the base pan is bent, ensure the mounting bolts aren’t too tight. If this is too tight, it can result in a bent base pan or a broken seal.

Always inspect the drain pan when the interior is leaking. If the drain pan is damaged, replace it. Clear out any debris plugging the drain outlets. This information was originally posted by experienced RV owners or technicians.

Leakage that only occurs in high winds

If the RV AC unit only leaks during rainstorms or when driving the unit in the rain, it means that water is getting in through another route. The water could be being forced under the mounting gasket or through other vents, seams, or roof openings.

Leakage only occurs when the unit operates in high-humidity conditions (80% relative humidity or higher).

If the unit leaks in humid weather, it could be on too steep of a slope. The drain pan may overflow if the RV is on a slope greater than 15 degrees.

Coleman RV Air Conditioner Leaking Water 

• The most common reasons a Coleman air conditioner will leak into the interior are the following:
• Clogged drainage: Dirt, dust, debris, gunk, and mold can block water flow, causing the AC to leak.
• Improper airflow: A dirty air filter or high humidity can cause the unit to freeze up. An AC freezing up can increase the amount of pooling on the roof and also can prevent the unit from properly draining.
• Condensate pump: If the condensate pump isn’t working right or is clogged, water may be unable to drain. Poor draining can result in pooling water collecting in the pan and leaking out.
• Gasket: A damaged or poorly sealed gasket can leak water inside. Ensuring the gasket is free from debris and secured appropriately is essential. Do not overtighten the gasket, as this can cause the gasket to leak.
• Rain Spouts and incline: Ensure the rain spouts do not have debris blockages. Also, water may not drain effectively off the roof if your RV is not level. Poor draining can result in pooling on the roof of your RV that can leak underneath a compromised gasket or roof seam.
• Drain pan: Water can leak inside if your AC drain pan is damaged or cracked. 

Jayco Air Conditioner Leaking inside

• The Jayco Air Conditioner leaks for the same reasons that many other RV Roof AC units leak. The most common reasons a Jayco Air conditioner will leak into the interior are the following:
• Clogged drainage: Dirt, dust, debris, gunk, and mold can block water flow, causing the AC to leak.
• Improper airflow: A dirty air filter or high humidity can cause the unit to freeze up. Dirty air filters can increase the amount of pooling on the roof and also can prevent the unit from properly draining.
• Condensate pump: If the condensate pump isn’t working right or is clogged, water may be unable to drain. Poor draining can result in pooling water collecting in the pan and leaking out.
• Gasket: A damaged or poorly sealed gasket can leak water inside. Ensuring the gasket is free from debris and secured appropriately is essential. Do not overtighten the gasket, as this can cause the gasket to leak.
• Rain Spouts and incline: Ensure the rain spouts do not have debris. Also, water may not drain effectively off the roof if your RV is not level. Poor draining can result in pooling that can leak underneath a compromised gasket or roof seam.
• Drain pan: Water can leak inside if your AC drain pan is damaged or cracked.

Are you interested in learning more about your RV and doing your own routine RV maintenance? Check out this RV maintenance checklist. Doing it yourself will save a ton of money, and it’s really rewarding.