Is There Water or Moisture Around Your AC Vents?Service Champions
  • CALL
  • East Bay (925) 308-5025
  • Sacramento (916) 231-9469
  • South Bay (408) 572-8065

Is There Water or Moisture Around Your AC Vents?

May 22nd, 2018

What are those water spots on the ceiling? Does it look as if the vents are leaking?

If you find water or moisture around your HVAC vents, take action fast! Continue reading to learn more about moisture and water damage around your home’s AC vents.


What causes condensation to form on the air ducts and then leak into your ceiling? Condensation occurs when humid air meets up with the cold air ducts. Think about condensation forming on a cold drink on a hot day. This problem is especially prevalent in the summer due to how hot the air is.

If you have insufficient duct insulation, condensate moisture can appear. Also if the duct boot—the part that connects the duct to the vent—is not sealed properly or is loose for any reason, condensation may appear.

This happens with your air conditioner because when you have cold air and cold vents but hot air on the outside, condensation will form. Condensation can then drip down and cause moisture on ceilings and walls.

Luckily, this issue can be treated and corrected. And the sooner the better. Spend the time to have the problem addressed professionally. Nobody wants moisture to turn into mold or mildew in their air ducts!

Causes of Moisture Around HVAC Vents

Insufficient insulation

You may need more duct or attic insulation in order to solve the problem. If warm and humid air is coming from the attic, this can cause condensation to form on the cold air ducts and leak. Ask your local HVAC professionals at Service Champions if attic and duct insulation services are the right solution for you.

Air leak

The water could be coming from an air leak in the vent or something called the duct boot. The duct boot needs to be properly sealed so cold air won’t escape. When cold air mixes with humid air that’s when the condensation and moisture occurs. Mastic sealant can help solve this problem, but speak with a professional first. Additionally, if you haven’t sealed all the seams and connections in your ductwork, we highly recommend doing so. Not only will this prevent the condensation issue we discussed, but you’ll also experience greater energy savings and more comfort. Learn more about DIY versus professional duct sealing.

What You Can Do About It

Check ductwork for moisture, mold & mildew

Condensation can lead to mold and mildew to form in your air ducts. If you identify or suspect mold or mildew is present in your air ducts, contact a professional right away. Mold and mildew is unhealthy, especially if the spores are being circulated around the home by your HVAC system. Address any mold issues immediately.

Seal gaps & schedule maintenance

Obviously the ideal solution is to have prevented the condensation in the first place. Schedule annual maintenance with Service Champions to ensure that your ducts and system is tight. Sealing gaps and regular maintenance are proven to improve performance and efficiency and lower energy costs as a result.

When it comes to energy efficiency and air flow, the tighter the better. Learn about our signature PureFlow™ Duct System. Air will not escape, and condensation will not be created as a result. Moisture can be avoided with proper care and repair of your system. Sign up for a home maintenance plan to ensure bi-annual professional inspections for your heating and cooling system.

Important: Ensure that the ceiling stain is from air conditioner condensation and not from a roof leak or plumbing concern. You may also see condensation and water stains around the bathroom exhaust fan for the same reason as the AC vents.

Learn what to do if you find water around the indoor air handler.

When left untreated, condensation can lead to expensive water damage and moldy conditions. If you notice water leaks around the HVAC system, Ask a Champion!

Schedule a Service Now!


Service Champions - East Bay
7020 Commerce Dr
Pleasanton, CA 94588

(925) 444-4444
(925) 598-1827 - Fax


Service Champions - Sacramento
4430 Yankee Hill Rd
Rocklin, CA 95677

(916) 777-4444
(916) 415-0687 - Fax

San Jose

Service Champions - San Jose
1735 Angela St
San Jose, CA 95125

(408) 777-9444


Service Champions - Concord
200 Mason Cir, Suite 200
Concord, CA 94520

(925) 444-4444


Service Champions - Livermore
96 Rickenbacker Cir
Livermore, CA 94551

(925) 444-4444


Come join our team
of Champions!”

Feedback Corner

24x7 Answering Service

Mon-Thu: 7am - 8pm
Fri-Sun: 7am - 7pm

Our quality service and guarantees have made us the best choice in Northern California. We look forward to hearing from you.

Send us Feedback

We would love to hear how your recent experience was. Please feel free to reach out to us.