How to fix a moldy smell in my laundry drain?

 
Identify the Source of the Odor
 

• Investigate whether the smell originates solely from the drain or if the washer or surrounding areas are also affected.
• Note if there is visible mold, slime, or residue buildup inside or around the drain opening that could be contributing to the odor.
• Determine if the odor worsens when water is being drained, which may suggest that stagnant water or trapped debris is causing the problem.

 
Clean the Drain Thoroughly
 

• Prepare a cleaning solution by mixing either a mild bleach solution (1 part bleach to 10 parts water) or white vinegar for a less aggressive yet effective alternative.
• Pour the solution directly into the drain slowly, allowing it to work on any mold and mildew buildup along the pipes.
• After letting the solution sit for at least 15-20 minutes, flush the drain with boiling water to help wash down any loosened debris and kill any remaining mold spores.

 
Scrub and Unclog the Drain Opening
 

• Use a long, flexible cleaning brush or an old toothbrush to scrub around the drain opening, paying attention to any visible buildup.
• If the opening has a removable screen or filter, remove it and clean it separately with warm water and detergent.
• Ensure all residue is dislodged by cleaning the edges and crevices of the drain thoroughly.

 
Clean the Drain Trap
 

• If possible, remove the drain trap (the curved section of the pipe) to inspect for accumulated sludge or debris that might be harboring mold.
• Soak the trap in a cleaning solution (either a bleach mixture or a strong vinegar solution) to break down any buildup.
• Scrub any remaining residue and rinse the trap completely before reinstalling it.

 
Flush the Drain Regularly
 

• Schedule a routine maintenance flush by pouring boiling water periodically down the drain to help prevent residue buildup.
• Consider using an enzyme-based drain cleaner once a month which can digest organic residue without causing harm to pipes.
• This regular action helps maintain cleanliness inside the pipes and prevents the development of mold-friendly conditions.

 
Improve Ventilation and Drainage
 

• Ensure adequate ventilation in the laundry area to help dry out any dampness that contributes to mold growth.
• Check that the drain is sloped correctly, allowing for proper drainage so that stagnant water does not remain in the system.
• If necessary, adjust or repair any plumbing issues that may cause water to sit, which can foster mold growth.

 

Homeowners and businesses in St. Louis and Nashville have found these guidelines effective in maintaining clean and efficient drains.