Why Do I Hear a Dripping Noise from My Air Vents?

Why Do I Hear a Dripping Noise from My Air Vents?

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A dripping noise in the air vents is the last thing any Atlanta area homeowner expects to hear while relaxing indoors on a hot summer’s day! This unusual noise creates concern and should be addressed right away to resolve troublesome conditions, avoid moisture damage and prevent reoccurrence. 

The HVAC pros of Estes Services discuss what could cause the dripping sound in your air vents and what to do to stop both the sound as well as the underlying issue. When a dripping sound needs professional assistance to solve, contact us for quick and reliable cooling repair service.

Possible Causes of a Dripping Noise in Air Vents

When you hear a dripping noise coming from your air vents, the sound may not be the only symptom present. Look at vents at the ceiling, and you may see water droplets dripping off the vents as well!

The actual water drips from your vents are typically caused by these HVAC system issues:

1. A Clogged Condensate Drain

If the air conditioner system’s condensate drain system is clogged, excess moisture stays in your home. The condensation is normally created by the cooling process and removed through the system’s drip pan and condensate drain line. Moisture that lingers in your home can manifest and cause moisture to form in your vents across your home.

Check your air conditioning system’s drip pan and condensate drain line for clogs. These components are located beneath the evaporator coils housed within the interior air handling unit, as they collect condensation that gathers and falls from the coils as heat is exchanged to cool the home. Clean out any algae growing in the drip pan as well as any other accumulated debris. 

If there is a clog in the condensate drain line, attach a wet/dry vacuum to the drain line’s exit on the exterior of your home, and run the vacuum for one minute to extract clogged material. If the clog does not resolve, call your HVAC professional to have the condensate lines cleaned and the clogs removed.

2. Air Leaks at the Vent

If the air vent does not fit snugly into the supply duct it is attached to, air may escape around the outsides of the vent as well as through its louvers. When this occurs, condensation might build and eventually leak down, causing dripping water sounds coming from your vents.

The air leak must be sealed to eliminate this moisture problem. Feel around the vent – if air escapes around the edges of the vent and not only through the grated portion, an air leak is present. Check the vent for damage as you may need to replace the entire vent to achieve a secure fit. Or, caulk around the opening to create a seal between the air vent and the duct.

3. Frozen Evaporator Coil

The air conditioner or heat pump’s evaporator coil can freeze up for a number of reasons, caused by issues including dirty air filters and refrigerant leaks, among other culprits. You won’t have cooling in your home when this happens – once the issue is discovered, the cooling system is turned off to allow the coils time to thaw. This is where a dripping noise in air vents may occur, as well as visible leaks from your vents.

As the coils thaw, there may be too much moisture for the system to effectively remove. Moisture can back up in the system and leak from your vents. Clogs in the condensate drain line also contribute to this issue, preventing the cooling system from draining condensation as the coils thaw.

If your evaporator coil thaws and causes a dripping noise in vents, be prepared to soak up any water that escapes the vents into your living areas. Ensure the condensate drain line is clear for the removal of moisture, and call your HVAC technician to diagnose and solve the root cause of your frozen coils.

Avoid Moisture Problems with Estes’ Help!

Dripping water from air vents isn’t always a simple disturbance – it can signal the possibility of water damage, both within your cooling equipment and to areas of the home surrounding the vents, such as ceiling materials, flooring below and furnishings. Solve these leaks and the cooling system issues that cause them when you call Estes Services to schedule an air conditioning repair visit.