Preventative maintenance goes a long way in keeping HVAC systems operating as they should be, but breakdowns can still occur. These complex systems are made of many components. Without being familiar with how HVAC units and their many parts work, diagnosing issues can be difficult. Especially when you’re managing large multifamily properties, it’s helpful to know about some of the most common causes of HVAC problems, as it can save you, your team, and your residents from a lot of frustration.  

Swollen Capacitors 

Air conditioners cannot run on their own when their capacitors stop working. The job of a capacitor is to start the motor and to help keep it running. It does this by sending jolts of the energy it stores to the fan. Without the jolts, the fan simply can’t get going. There are a few ways to tell if a capacitor has gone bad. A visual inspection is often the easiest, as a swollen capacitor is a problematic capacitor.  

What causes capacitors to swell? Gas is created when the conductive electrolyte within the capacitor decomposes, which happens with time or damage. Capacitors have a lifespan that can vary but is definite. The HVAC systems that house them can outlive them, meaning there naturally comes a time when a capacitor must be replaced. Swelling is a sign that the time has come, as any swollen capacitor has reached its end. You can tell that a capacitor is swollen when its shape has become altered, usually resembling a can of soda that was in the freezer too long and is ready to blow.  

Contactor Connection Woes 

A contactor is known to be one of the most reliable electronic components, as they tend not to wear out with time. But that doesn’t mean that issues involving them cannot arise. In HVAC systems, contactors work with the thermostat to help turn the unit on and off. It closes to create a complete electrical circuit that allows the system to run and, when it opens, the circuit is rendered incomplete and the system shuts off. It’s possible for an HVAC contactor to be stuck closed, leaving the machine to run continuously until power is shut off from it by other means

It may be easier to tell that the contactor is to blame when a system won’t shut off than when it won’t come on. There are many issues that can prevent an HVAC unit from starting. One way to tell that the contactor is at fault is that the thermostat clicks but nothing happens. By this you can know that the contactor has either died out or isn’t getting a good connection.  

Burned Out Wires 

There are a number of wires within HVAC systems. In addition to the power wires that connect the system to the electrical source, there are also wires to the compressor and the capacitor. Any of these can be burnt by overheating and other electrical issues. The smell of the wire burning is one tale-tell sign of a problem. Another is the inside of the unit being charred. From there, it’s just a matter of locating the affected wire and the issue that caused the wire to burn. This is important not just for restoring the system to prime operating condition but for preventing a future fire hazard.  

Taking the Hassle Out of Maintaining HVAC Systems 

Maintaining, repairing, and replacing HVAC systems is a big but necessary undertaking for multifamily properties. Some of the related tasks are quite simple once the issue at hand is identified and others require the care only a professional can give. Burnt wires, swollen capacitors, and contactor connection issues are just a few of the most common HVAC problems that can occur even in systems that are properly maintained. How well they are addressed can have a major impact on the life of the system.