Basic air conditioning and refrigeration principles are very similar whether you are dealing with a large commercial HVAC or a residential system. However, the commercial HVAC is much larger and has many more points of fault. What may seem intuitive based on a home system is not always accurate.
For example, it is a common misconception that most commercial HVAC issues start in the compressor.
The compressor is an essential component and does much of the work of keeping the system functional. If there are problems in the operating environment, it is possible for a compressor to fail well before the ten years of service it should offer. However, early failures are relatively rare.
It’s just as important to keep an eye out for other issues that can affect performance.
Regular maintenance of your commercial HVAC can keep you apprised of how it is doing and put you in a position to resolve small issues before they become big ones. That can save you thousands of dollars in the long run, but often requires some detective work.
If you are experiencing any of the following symptoms, a full system inspection is crucial:
- Poor indoor air quality (IAQ) including noticeable odors from the HVAC vents
- Unusual sounds, such as banging or grinding, especially as the power cycles
- Inconsistent airflow or temperature control throughout your building
- Lost system efficiency, which may be noticeable in higher energy bills
Many of these issues are warning signs for a larger system failure around the corner. While some of them may be easy to solve – low air quality can mean a filter needs cleaning or replacement – others point to more severe mechanical faults somewhere in the system. The question is where.
If your commercial HVAC isn’t working, check for these problems:
1. Lapse in HVAC System Maintenance
A preventative maintenance program is absolutely essential for extending the life of your HVAC system’s various components. If there has been a lapse of a quarter or more in maintenance, prepare for a full system inspection to identify emerging problems and get you back on track.
No matter how long it has been since maintenance was performed, it’s not too late to return to a better schedule. Your HVAC team should thoroughly document all their observations, repairs, and replacements so that future changes in the system are easier to pinpoint and perform.
2. Clogged Air Filters or Ductwork
In a large commercial HVAC system, most air filters are designed to be replaced rather than cleaned. The air filters capture pollutants and take them out of air circulation, protecting the health and wellness of those who rely on your building. They may be replaced anywhere from once a year to quarterly.
While filter replacement is straightforward, there is another potential problem for older buildings: Failed ducts. Ducts in older construction may be much narrower than what building codes prescribe today. Ducts that routinely become clogged may need to be replaced.
3. Leaking Refrigerant
Leaking refrigerant will bring your HVAC system to a halt within a short time. If you are getting complaints of “lukewarm” air, this is the first place to check. Airflow may be normal, but spaces will not be cooled. Depending on the nature of your leak, it can damage several system components.
As the level of refrigerant declines, the condenser works harder, which may result in failure. Remember, though, that the wrong amount of refrigerant is only one possibility. Check to be sure the right refrigerant is being used based on your HVAC system specifications. You may need to replace your refrigerant.
4. Declining Thermostats and Other Control Systems
Today’s commercial HVAC systems are increasingly reliant on a sophisticated array of sensors to optimize their output and balance load. The thermostat acts as the “brains” of the system: If it fails, you will get inconsistent performance. Thermostats tend to become less accurate over time.
The most advanced HVAC control systems now provide you with a variety of diagnostic tools for ensuring they are properly calibrated. Some may even run self-diagnostics and give you information you can act on. If a new thermostat is needed, consider the savings of an energy efficient model.
5. Improper Air Balance
Heated and cooled air may travel through many feet of ducts before emerging in a room. Dampers help to optimize the flow of air by reducing airflow in one line and enabling more throughput for conditioned air. If some rooms heat or cool faster than others, the dampers may need to be rebalanced.
Complete HVAC maintenance will save you time, money, and aggravation. If you discover that your compressor is the culprit, a remanufactured commercial compressor is an ideal solution. You’ll save anywhere from 20% to 40% compared to OEM wholesalers and cut several weeks off your turnaround time.