Why Does My RV Air Conditioner Leak When it Rains?

Most RV air conditioner units go on the roof. While this seems practical, it is a high-risk area when it rains. Any hole or opening on the roof is an opportunity to let water into the RV.

While factory RV air conditioners rarely leak, aftermarket units often leak – especially if you didn’t install yours well.

Sometimes, even stock air conditioners will leak if you put undue pressure onto your RV’s roof.

some of the most common causes include:

  • Damaged or missing gaskets
  • Loose or missing bolts
  • A damaged or missing shroud
  • A gap between the unit and the roof
  • Blocked drain holes
  • A dirty evaporator coil
  • Rood damage or deterioration

A Missing Shroud

The shroud is that big sheet metal and plastic cover you see jutting off the roof of your RV. It covers most of the AC unit, protecting it from dirt, debris, water, leaves, and impact damage.

Check this too: Carrier RV Air Conditioner How to and Troubleshooting Guide

It has vents to the side and a solid top to make it harder for dropping debris and water to get to the RV unit. It also has a rubber gasket at the point it meets the RV roof making it the first line of defense against pooling water.

This simple unit can keep a considerable amount of water from getting to your RV and the installation area hence the hole leading to the inside.

If the cover is missing or damaged, your AC unit will have to deal with more water than it was designed to. This could either damage the AC unit or lead to water leaks.

Loose or Missing Bolts

Bolts on the shroud and the AC unit itself do more than hold these components in place. They generate the pressure needed to create a waterproof joint between the AC unit and the roof.

Firmly bolts will squish gaskets enough to create an air and water-tight seal. If the bolts are loose, the gaskets will no longer mesh perfectly, and some water can seep in through the openings.

A missing bold could also make it harder to torque down the shroud or AC unit enough to create a uniform gasket seal with the RV roof.

It could also be dangerous, making it easier for the air conditioning unit to wiggle loose the more you drive.

  • While in the RV, open the interior AC panel to access the bolts
  • Replace any missing bolts (most ACs have four, some have three)
  • If you can find torque specs in your user manual, ensure the bolts are torqued to spec
  • Otherwise, turn each bolt slowly to ensure it doesn’t yield very easily and ensure all are tightened the same
  • Overtightening will over squish the rubber gasket rendering them inefficient.

Damaged, Faulty, or Missing Rubber Gaskets

A rubber gasket sits between the AC unit and your roof to give a better seal than metal to metal. Your gasket should last for a couple of years before it starts cracking and losing its integrity.

Your gasket should also fail sooner if you keep fiddling with your AC unit or over tighten the AC unit.

An ideal installation squishes the gasket to about 1/2 of an inch. Consult your user manual for specifications and guide on torque specs for perfect installation.

Consider replacing your AC gaskets if:

  • They are missing
  • They are cracked, warped, or partially disintegrated
  • They are squished flat due to over torque

Blocked Drain Holes

All air conditioning units create some water and condensation as they work. RV air conditioner manufacturers install drainage channels, gaps, and holes that should remain unobstructed for optimum performance.

In some models, this will lead to a gap between the air conditioner and the roof during installation. While this might seem like the source of your leak problems, finding a way to block the gap will force the condensation and water to leak into the RV.

You don’t have to worry about them because there is a gasket on the inner side of the channel that makes the entire thing air-tight.

A Deteriorating or Damaged Roof

As your RV ages, the roof could deteriorate and start sagging. The sagging makes the surface uneven, making it harder for the AC unit to maintain a tight top.

Any damage to the roof could also lead to the same problem. This could be as simple as something dropping on the roof to someone walking on it while stepping on the wrong spots.

Check this too: How to Check Ammonia Levels in an RV Fridge

Have the roof repaired and realigned. If the AC unit can’t get a perfect seal, you can look for a bigger aftermarket gasket or use two gaskets for a better seal.

Check Your Evaporator Coil

If your evaporator coils are dirty, they will not drain water as fast as they should. This will make the water your AC creates when working accumulate, leading to leaks even when it’s not raining.

Consult your manual to identify the evaporator coil location and clean it using a vacuum cleaner, some rags, and a degreaser.

Oscar

In his spare time, Oscar loves tinkering with electronics. Solar panels, wiring, old TVs and sometimes DIY powerwalls. When he is not busy trying not to electrocute himself, you can find him in the garden tending to his vegetables and chickens.

Recent Posts