What You Should Know about Residential Rooftop HVAC UnitsWhile everyone’s familiar with the typical residential “split” central air conditioner, the rooftop HVAC unit is now beginning to be seen in home installations, too. The standard split system includes an indoor evaporator coil along with an outdoor condenser coil next to or behind the house. The rooftop A/C, however—also known as a packaged system—consolidates coils and other HVAC components into a single unit. It’s usually mounted at or near the peak of the roof and blows cool air directly into ductwork routed through the attic.

Here are a few points of comparison and contrast between the standard split system and the rooftop HVAC unit:

  • Since all parts of the rooftop system are combined into one box, routine maintenance, troubleshooting and repairs are more streamlined. However, the structure of the roof must be able to support the considerable weight of this larger unit. Reinforcement may be necessary and installation can be more complicated than a standard split system.
  • Cool air from a rooftop unit enters household ductwork at the highest point of the structure. As colder air sinks naturally, coolness spreads very efficiently through the ductwork below into all parts of the house. However, higher temperatures caused by exposure to direct sunlight may cause a rooftop unit to run longer cycles to disperse heat on a very hot summer day.
  • Thefts of the outdoor condenser coil of a split central air conditioner have risen dramatically in recent years. Mounted in an inaccessible location high on the roof, thefts of a rooftop HVAC unit are rare. Installation up on the roof, however, also means that the unit is more vulnerable to weather-related wear and tear so routine preventive maintenance requirements may be greater.
  • While the outdoor condenser coil of a split system may be effectively disguised behind latticework or strategically-planted bushes in the back yard, a rooftop unit is harder to hide. Some homeowners don’t prefer the conspicuous appearance of the unit on the roof.

For more pros and cons of a rooftop HVAC unit, contact Mowery Heating, Cooling and Plumbing.

Our goal is to help educate our customers in Brownsburg, Indiana and surrounding areas about energy and home comfort issues (specific to HVAC systems).