What Can Go Wrong With Commercial Rooftop Package AC Units?

Posted on: 14 October 2022

Rooftop package units (RTUs) are a common solution for commercial air conditioning needs. These units package the most vital system parts in a single enclosure, reducing installation costs, improving efficiency, and often providing easier maintenance and repair access. They also don't require much interior space, which can be a huge benefit for commercial applications.

However, RTUs also spend their lives exposed to the elements. While all air conditioning condensers live outside, the evaporator and associated hardware in RTUs must also contend with temperature swings, moisture, and other environmental concerns. As a result, you may find yourself facing these three common problems with rooftop commercial air conditioning systems.

1. Rodent Infestations

Rodent infestations are a concern for condenser units located at ground level, but they can also be an issue for package rooftop units. Since the entire HVAC system sits on the roof, squirrels, chipmunks, and other curious pests can make their way inside, especially during the cold winter months. These animals can cause numerous problems, including chewing on and damaging wires.

If your air conditioning system worked well before the winter and now seems to be suffering from intermittent failures, it may be due to minor wire damage caused by curious or hungry pests over the winter. Fortunately, an experienced commercial HVAC tech can usually spot the signs of an infestation and repair or replace any damaged wiring.

2. Blower Failures

Blower failures can occur on any air conditioning system, and rooftop package units are no more prone to these failures than typical split systems. However, the location of a rooftop unit can make it harder to notice the early warning signs of an aging blower. Blower motors may produce squealing, grinding, or other harsh noises as they fail, but it's typically impossible to hear with the unit on a roof.

As a result, you may miss the early warning signs of trouble and only realize a problem exists when your customers or employees complain of hot temperatures. If you notice a reduction in airflow, inconsistent airflow rates, or a blower that randomly cuts in and out, you may want to have a technician look at your system before the blower fails entirely.

3. Wire Corrosion

Outdoor elements of an air conditioning system include substantial protection from moisture and other environmental hazards. However, rooftop units can face extreme conditions, especially in humid or rainy climates. Poorly maintained systems are especially vulnerable since protective panels may be loose or rusty, allowing moisture to enter the system.

Wire corrosion can lead to tripped circuit breakers, damaged contactors or relays, or other problems that can stop your system from functioning. Since wiring issues can be potentially dangerous, contact a professional commercial AC repair service if you notice your building's system shutting down randomly or frequently tripping its circuit breaker.