Condensing Coil: how the AC condenser coil works in Roswell homes

Condensing Coil of a residential HVAC system

The condensing coil wraps around the outdoor unit and releases the heat your system pulled out of the house. Hot refrigerant from the compressor runs through it, outside air carries the heat away, and the refrigerant turns back into a liquid.

How it works

The coil is a long run of copper or aluminum tubing woven through thousands of thin fins. The more surface stays clean and open, the easier it is to dump heat.

When fins are matted with grass clippings, dryer lint, pollen or cottonwood fluff, the system can't shed heat. Pressures rise, the compressor draws more power, and cooling capacity drops right when you need it most.

Bent fins from lawn equipment or hail also block airflow. A fin comb can straighten small areas; large damaged sections may affect performance for good.

Signs of a problem

Visible lint or debris matted on the coil sides
Very hot air coming off the top of the unit
Rising power bills in summer
System trips off on high pressure
Flattened or bent fin sections

Simple upkeep

Point mower discharge away from the unit
Keep shrubs trimmed back 2 feet
Rinse the coil gently each spring after pollen season
Keep dryer vents from blowing onto the unit

The condensing coil in Roswell homes

Tree cover drops leaves and seed pods into outdoor units, and humid crawlspaces are hard on ductwork and drains. In Roswell's mix of historic homes around Canton Street, wooded 1980s subdivisions and many basement and crawlspace installs, we see condensing coil issues most often in homes around Historic Roswell, Horseshoe Bend, Martin's Landing.

What our technicians check: We clean condenser coils from the inside out with the fan removed, which pushes debris out the way it came in rather than packing it deeper.