Coil Cleaning in Houston, TX

What coil cleaning actually involves in Houston

A fouled evaporator coil fails slowly, then expensively. Airflow drops. The coil runs colder than design. Condensate blows past the pan edge instead of draining. Most Houston air handlers sit in the attic, directly over a bedroom ceiling. The primary pan rusts, the secondary pan fills, and the drywall tells you months late. Restricted airflow also lets indoor humidity climb higher than it should, and that is where settled organic dust starts supporting mold.

The dirt arrives from the return side, not the supply. Unsealed return plenums and wall-cavity returns pull attic fiberglass and gypsum dust straight to the blower. A single undersized central return raises velocity and causes filter bypass at the frame. That debris felts into a mat on the upstream coil face. It is packed, not loose. Shop vacuums and spray cans barely touch it.

Real cleaning means opening the plenum. In 1960s-80s ductboard plenums that often means cutting an access panel and resealing it properly. We work both faces, rinse low-pressure with drainage controlled to the pan, then flush the drain line and trap. The blower wheel usually needs the same attention.

Cleaning alone is a repeat visit if sagging flex and slipped boot collars keep feeding the return. Access difficulty (attic versus closet) drives the labor more than anything.