Troubleshooting The Constantly Running AC Unit

When the temperatures climb well into the 90s and beyond here in the Pacific Northwest, we know we’re in for a long, hot summer. When they dip back down into the 80s and 70s, even for a short while, it can be a welcome relief. That is until you walk into your office and find the AC system running full blast day and night.

When your air conditioner runs without shutting off, or it cycles on and off continuously, there are several areas of concern. If the AC unit is running 24/7, it’s using way too much electricity and elevating your electric bill. It’s also causing undo stress on the unit itself, which will shorten its life overall.

But above all that, it’s cold. And it can be very difficult working eight hours a day in an environment that leaves you needing gloves to survive.

While there are many things that can be wrong with your AC unit, these are the most likely problems.

Dirty Evaporator Coil

When was the last time the evaporator coil was cleaned and conditioned? Dirt and debris can easily get into the AC unit and cover the coil, impeding the cooling process and making it more difficult to maintain the correct temperature. This can happen even if it was cleaned a few months ago, especially if it’s been working overtime during this recent heat wave. A regular maintenance check will allow a technician to clean and maintain an evaporator coil and keep it running efficiently no matter what the temperature is outside.

Frozen Evaporator Coil

If your unit is blowing warm air from the supply vents, it can be an indication that the evaporator coil has frozen. In order to avoid damage to your AC unit, turn off the system and call in a technician right away.

Clogged Air Filter

Air filters are designed to filter and allow a clean flow of air into the AC unit. Over time, this filter will collect dirt and debris, which restricts the amount of air allowed into the system. Without enough air flowing over the coils, the system can cool the air to the proper level, and keeps running all the time.

Low Refrigerant Charge

If the AC unit doesn’t have enough refrigerant in the system, it can’t cool the space. This often occurs when there is a leak in the system. When this happens, the unit will keep running trying to meet demand, causing the system to work harder than necessary. The first line of action is to find the leak and repair it before adding more refrigerant.

Faulty Thermostat

If your thermostat isn’t working correctly, it won’t know when to turn off the unit as it reaches the proper temperature. Check to see if your thermostat matches the actual temperature in your room or building. If it’s below, there’s a good chance your thermostat needs replacing.

Blower And Fan Problems

If the blower motor isn’t producing enough air for your system, or the fan isn’t running at a proper speed to push the air into the system, it can cause the system to run too much. It may be something as simple as cleaning grimy fan blades, or adjusting the speed of the fan.

Improperly Sized Unit

Have you recently renovated your space? Have you changed wall locations and room sizes without upgrading your AC unit to fit the new space? A HVAC professional can analyze your current space to determine the proper load requirements, and make recommendations for how to improve the efficiency of your system.

Many of these issues can be prevented with regular maintenance of your HVAC system. When was the last time your equipment was serviced by a professional technician?