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Why Are There Water Stains Around Ceiling AC Vents?

by vscontent on May 18, 2018

Why Are There Water Stains Around Ceiling AC Vents?

Do you notice water stains around your ceiling HVAC vents? This is a common frustration for many homeowners.

Ceiling tiles are a porous material that are great for showing every little bit of moisture or water that comes in contact with them. If you notice a ceiling stain, act fast! Stains often indicate a more serious problem that should be investigated right away.

Why Are There Water Stains Around My Ceiling Vent?

  1. Inadequate Insulation Around Ductwork

When warm, humid air comes into contact with a cold surface, condensation will form. Anyone who has had a cold drink on a warm day will know about this effect.

Well, the same thing happens when warm air contacts cold air ducts. Since the cool air conditioned air inside the ducts are colder than the outdoor air, condensation forms and can possibly drip below and cause ugly ceiling stains.

To help prevent condensation formation, air ducts should be properly insulated. Not only will it prevent damage from condensation, it will also save you a lot of money on heating and cooling bills.

To prevent the possibility of condensation on your air ducts:

  • Ensure proper duct insulation
  • Check for proper insulation around vent “boots” (the metal part that connects the ducts to the vent)
  • Seal duct leaks

If your vent boot isn’t attached correctly, cold air can escape and mix with the humid air, causing condensation. While you may be able to fix the air leak with mastic sealant, it’s probably best to contact a professional for help.

Contact a professional HVAC company for help sealing and insulating your duct system.

  1. Air Leaks

If there is an air leak around your vent boot, cold air could leak out and cause condensation around your vents. Look for air leaks around the bent, where the vent boot attaches to the duct, and between the vent and the drywall.

If the problem vent is hard to access or you can’t find and seal the leak yourself, contact a professional HVAC technician. 

  1. Proper Airflow

Better, higher airflow will help dilute the supply air temperature and reduce or stop the condensation.

To ensure proper airflow:

  • Clean or replace dirty air filters. You should check air filters every 30 days. Learn more about air filtration.
  • Perhaps set your blower to higher speed.
  • Make sure you schedule professional HVAC maintenance twice ever year. This will make sure your evaporator and condenser coils are clean.
  • Go around your home and make sure all supply and return vents are open and unobstructed.
  1. Condensate Leaking from Indoor Air Handler

Is liquid pooling underneath your air conditioner? A common summer complaint, we receive calls from concerned homeowners about the 

If you have a clogged filter, a leak becomes more likely. Dirt and debris keep air from moving freely. The result is that air will freeze in the unit. When it melts, the water drips from the air vents. If you are seeing water on your ceiling or walls near air conditioning vents, then a dirty air filter is a likely reason for the leak.

It is recommended that homeowners change out the A/C air filter every 30-60 days or as indicated by the filter. Keeping up with HVAC maintenance will save you a lot of money in repairs or leaks later on.

Regular cleanings don’t just fight off clogs, but also bacteria and other unsanitary accumulations.

Other Causes of Water Stains

If it’s not a problem with your air ducts or HVAC system, you could have a leaking pipe. Your cold water pipes may also be producing condensation.

The other possible source of water stains on your ceiling is a roof leaks. Contact a plumber if it is pipe related and a roofing contractor for any roof-related damage. 

If you notice any signs of mold around your duct or HVAC system, contact a professional HVAC contractor.

Prevention Is the Best Cure

Until spring is in full swing, many people will continue to rely on their home’s heating system around the clock. The more your HVAC system is used, the more it needs to be maintained. Swapping out the air filter is key to HVAC maintenance and performance.

We strongly advise our customers to sign up for an HVAC Maintenance Plan because it is a lot more efficient and economical in the long run.

Contact Pacific Heating & Cooling for award-winning HVAC service in the area. If you have any questions whatsoever, don’t hesitate to contact our experts.