Why is water coming out of the vent pipe?

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It is not normal for water to leak from the vent pipes. When it does, it indicates that there is a fault in your system. Check for cracked or rusty collars and torn rubber boots on the vent pipe. Water could also leak due to broken seams on the metal bases, which cause the water to seep in.

Why would there be water in a vent pipe?

Your vent pipe regulates air on your plumbing system. It ensures water and waste flows through the pipes that drain out of your house and prevents the creation of a vacuum that could result in slow or no drainage. In fact, clean drain pipes can only effectively drain water and waste when the vent pipe is working correctly.

Each plumbing fixture needs air to push the water through the drainage pipes in your home. Vent pipes work alongside drain pipes, only that they don’t hold water.

Your vent pipes also serve to remove sewer gases from your home. It’s normal for these gases to flow into your house from the sewer system. If you leave the gases to build up, it would not only cause a foul odor, but it can also be dangerous.

Have you ever wondered why constructors place the plumbing vent pipe on the roof? It has to stay away from the windows and air conditioning systems so that the foul odor doesn’t get back into your home.

If the vent pipe has a blockage, it could cause negative pressure to build up in your drainage system. Eventually, water won’t be flowing out of your home and could start leaking if your drainage pipes have some cracks.

While you can solely fix many forms of drainage issues, a blocked vent can be a tad complicated. If you often have drainage problems, a blocked vent might be the cause.

When installing a new sink, you need to ensure that it has proper ventilation. There are four common problems that could cause water to leak around your vent pipe. These are:

  • The rubber boot on the pipe has a crack, tear, or has rotted away. This causes water to seep into the house through the pipe.
  • Cracked or rusty collars around your vent pipe could allow rainwater to collect in the vent, and the water could eventually drip into your home.
  • Broken seams on the metal bases. This causes water to seep in.
  • Loose nails could expose some holes in the roof that let water through.

Why is water coming out of the vent pipe?

Vent pipes are also known as roof jacks or plumbing jacks. They are the pipes that protrude from your kitchen and bathroom and allow gases to escape. Although roof vents are vital for maintaining a balance between air intake and exhaust, excessive cold, heat, cold, or wind can weaken and damage the watertight seals around the roof vents over time.

Your vents may then spring leaks as a result of this. The water that seeps in can eventually create mold and damage the structure if left uncontrolled.

While there are several things that would cause water to drip an AC vent, it should not happen, and you need to fix it as soon as you notice the problem. The common causes of water dripping from an AC vent include:

Air Leaking Around the Vent

All the air in the vent should flow through the grates. If some air is able to escape from inside the vent, it could condense, build up and then start dripping.

The easiest way to fix this is to reach up and feel the sides of the air vent for any air escaping from around the sides. If you feel air escaping from anywhere other than the grates, purchase some caulk and use it to seal the leak.

Clogged Condensate Drain Line

Having a clogged condensate drain line causes condensation to accumulate and drip from the air vents. This especially occurs if you have installed your air conditioning system in the attic or any upper level in your home.

To check whether you are dealing with a clogged condensate drain line, take a look at your condenser unit and see if the drip pan is full. This is an indication that you are. You could also check for rust on the furnace. Corrosion on your furnace puts it at risk of failure.

To fix this, change the air filter regularly and allow the unit to return to its standard functionality.

Condensation From Uninsulated Ducts

If your air ducts primarily run through the attic, keep in mind that many attic spaces are not insulated. Many attic spaces lack insulation. If your air ducts majorly run through the attic, the poor insulation could cause condensation to accumulate within your system and drain through the AC vents.

If you have access to the attic, fixing this should not be a problem. Get special air duct insulation and wrap it around the ductwork.

Broken Sump Pump

If you have cleaned your condensate drain line and there is still a lot of water in the drip pan, then the culprit could be your condensate pump. Most pumps usually contain a float switch that turns the pump on when the water reaches a specific level.

To fix this, look for the float switch and try to move it up and down to see if the pump turns on. In some cases, the float switch gets stuck due to limescale or scum build-up. If the switch is inconsistent, try cleaning the bucket to remove the build-up and check if there’s any improvement in performance.

If the pump is still not working, you may need to acquire a new pump. You can fix this yourself or call a professional to install it for you.

Does rainwater get into the vent pipe?

Vent pipes normally penetrate through the roof in several locations of the house, and each of them needs proper maintenance to keep water out. Your vent pipes may leak during heavy rain if they have cracks along their length.

During installation, you should fix each vent pipe with a flexible boot that seals water around the surface of the vent pipe. These boots will vary in flexibility, quality, and longevity. After a while of usage, many vent pipe boots begin to harden and consequently get brittle due to exposure to a harsh environment.

The hot and cold cycles of the sun and cold winds take a negative toll on your roof. If you don’t check and control this, the vent pipe boot cracks and your roof remains vulnerable to a water leak.

Among the things that you should never overlook in your house is your vent pipe maintenance. If you fit your roof with poor-quality vent pipe boots, you might need to do more maintenance and replacement over your roof’s lifetime. Regular maintenance could save you from replacing them or having to do a roof repair.

Preventing rainwater from getting into your vent pipe

  • Apply flexible roof sealant to any gaps, flashing, and loose shingles around the vent pipe.
  • Replace worn out vent pipe boot, shingle, and flashing around it to provide a long-lasting fix
  • Overlay your old vent pipe boot with a new one, then caulk and seal it.

However, caulking around the roof vent is a temporary solution and could cause more problems as it may mask the damage that the leak has caused in your home.

If the damage is extensive, it’s best to call a professional roof repair service to assess the roof and determine an appropriate solution. Generally speaking, it is best to replace your roof vents with new ones and ensure you install them with caulking and rubber-washer screws.

Conclusion

It can be quite irritating when there is water leaking inside your house. Fortunately, if it is leaking from your vent pipes, you can almost always repair it yourself with the instructions above. If you experience difficulty, you can always call a professional from an HVAC company to help you with diagnosing and fixing the issue.

Sources

https://www.austinlonghornroofing.com/blog/roof-leaking-around-vent-pipe#:~:text=Here%20are%20four%20common%20problems,into%20a%20building%20or%20home.

https://www.sansone-ac.com/water-dripping-from-ac-vent-heres-how-to-fix-it/

https://aplusairconditioning.com/water-dripping-air-vents-ac-troubleshooting/

Marco
Marco
Meet Marco, a lifelong tinkerer and DIY enthusiast, developed a passion for plumbing after fixing a leaky faucet in his own home. Years later, he turned that passion into a thriving business, Amarco Plumbing, where he shares his knowledge and expertise with the community.