A new air conditioner is a significant investment, which makes it vital that you have your cooling system professionally maintained and do everything you can to protect the lifespan of your AC. One of the most significant factors that will determine how long your AC lasts is how long it runs. After all, the more hours it runs for, the more substantial wear and tear it will receive. With this in mind, here is a complete overview of how long your AC can run and what to do if the system is constantly running.

How an AC’s Cooling Cycle Works

To understand how long an air conditioner can and should run, it’s necessary to look at how AC cooling cycles work. It takes an AC at least fifteen minutes to complete one entire cycle from the time the thermostat signals the system to turn on until the home is cooled to the set temperature and the system shuts off.

During this time, the condenser supplies cold refrigerant to the evaporator coil inside the building. The refrigerant then works to absorb heat from the air coming into the system and cool the air before it is pumped out through the supply vents. The excess heat absorbed by the refrigerant is then pumped back to the condenser coil, where a fan helps to release the heat and recool the refrigerant.

Fifteen minutes is the minimum time it takes for the system to start-up and then cool the home. If the system runs for less than 15 minutes, it indicates that the condenser is short-cycling or getting stuck in start-up mode. The unit will usually turn on and off constantly without completing a full cycle or cooling the home when this happens. This will not cause the unit to use much more energy, but it could also ruin the system. If you notice this happening, you must have the system professionally inspected and repaired or maintained. If not, it could eventually burn out the condenser motor, in which case you’ll need to replace the unit.

If everything is working correctly, the system should usually perform two complete cycles an hour, lasting around 15 to 20 minutes. In hotter or more humid conditions, a cycle may last for an hour or even more before the home reaches the desired temperature. This is also true if, when you turn the AC on, the temperature inside the house is more than 5 to 10 degrees warmer than what you have the thermostat set to.

On extremely hot or muggy days, it’s fairly common for an AC to run almost constantly during the hottest parts of the day or turn on again within a few minutes of completing a cycle. This puts added stress on the system and increases wear and tear on its components. The easiest way to avoid this issue is to set your thermostat to a higher temperature to see if the system runs less frequently. If the system still runs constantly after doing this, you’ll need to have your entire AC system inspected.

Issues That Can Cause an AC to Run Constantly

Numerous possible issues can cause both short-cycling or an AC to run constantly. It could be something as simple as a clogged air filter or dirty evaporator coil if you’re lucky. These issues can restrict the amount of air coming into the system and make it more difficult for the air handler to circulate the conditioned air throughout the entire building fully.

Similar issues can also occur if your ductwork is damaged or leaking air. In this case, much of the cooled air will be lost through any holes or loose connections in the ductwork. This can cause the AC system to run for more extended periods and more frequently to circulate the air and cool the home properly.

Another possibility is that your thermostat isn’t working correctly and not signaling the system to shut off. This can also happen if the thermostat is located in a hotter area than the rest of the home. These issues are usually relatively easy to spot as they will generally cause the house to be much colder.

Your AC running constantly could signify a more severe issue such as a refrigerant leak. If there is a leak in one of the refrigerant lines, the system will eventually not have enough refrigerant to properly cool the home. Most commonly, this will result in the evaporator coil or condenser coil freezing up. If you attempt to run the system when it is frozen, the blower fan or condenser motor may overheat and burn out. Luckily, this issue is relatively easy to spot since it will usually cause the system to start blowing hot air out of the vents.

One common cause of short cycling is that the AC unit is too large for the home. Alternatively, if the unit is undersized, it can lead to it constantly running without ever being able to achieve the desired temperature fully. In either case, your comfort will suffer, and your energy bills will be much higher. If the AC is too large, the only real solution is to replace it with an appropriately sized unit. If the system is undersized, you could add supplemental cooling such as a window or portable AC, but replacing the unit is usually the best option.

There is also a possibility that the issues aren’t related to your HVAC system at all. Specifically, it could be that you don’t have enough insulation in your attic or walls. A lack of insulation can cause a tremendous heat gain and allow much of the cooled air to escape quickly. These issues can make it nearly impossible for your cooling system to keep up even if it is appropriately sized and working as it should.

Professional AC Repair, Replacement and Maintenance Services

If your AC is constantly running, you’re spending far more money to cool your home and risking the life and health of your cooling system. At Bel-Aire Heating & Cooling, we can help prevent these issues by repairing whatever problems your system may have. Our certified HVAC technicians also help extend the lifespan of your cooling system with regular preventative maintenance. We are one of the biggest Lennox Premier Dealers in Michigan and can help when it comes time to replace your AC or any other HVAC equipment.

Free cost estimates are available for all services, and financing for new equipment is also available on approved credit. With our 100% satisfaction guarantee, you can rest assured that all work we perform is done to the highest possible standards. We have been providing exceptional cooling and heating services to customers in the Portage, Grand Rapids, and Three Rivers areas since 1961, and we’d be happy to show you what makes us the best HVAC company in Western Michigan. Give us a call today to see how we can help you remain comfortable all year long.

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