Does your AC run continuously without shutting off? Is it humming away 24/7 without a pause? A constantly running AC may be an indicator of major problems requiring professional assistance.
Keep reading to discover the most likely reasons your air conditioner is stuck on and when to call an HVAC tech.
You Never Feel the Breeze
We’ve all been there – it’s the hottest day of summer, and you turn the AC down to 65°, but your home is still boiling hot.
You glance at the thermostat and realize the AC has been running constantly for hours and hours. But you and your AC run all day, and the best it can do is keep your place above 80°.
If this situation sounds familiar, then your unit probably has a refrigerant problem. Refrigerant is the fluid inside the AC that absorbs heat from the air in your home. One of the most common reasons an AC runs all day without shutting off is that it doesn’t have enough refrigerant. Your unit is running constantly trying to cool your home, but without enough refrigerant it simply can’t get the job done.
The Air Filter is Clogged with Dust and Debris
How long has it been since you checked or replaced your air filter? A filthy filter that is clogged is too dirty and makes your AC run constantly to push air through.
Changing the filter each month will help air flow, reduce the strain on the unit’s system, and help it to cycle on and off as it should.”
Healthier, optimal filtering is essential to maintain frequent function of your AC. During peak use seasons, check the filter each month and replace it: The new filter should be of good quality and properly sized. All of this forces your system to work much harder than necessary to cool your home.
There’s a Serious Refrigerant Leak
A more serious refrigerant leak can make an AC run constantly, as well, although simple lack of refrigerant will do it too. If it has a leak in the refrigerant lines or evaporator coil, it should get repaired by a professional immediately.
With a major leak, refrigerant will not stay in the system regardless of how many times you recharge it. AGAIN, you’ll just pay for expensive refrigerant refills every couple of weeks and keep your AC running 24/7. Sooner or later, you’ll wear your AC out and burn it up trying to make up for the leak.
Thermostat Has the Wrong Temperature
Issues with the thermostat can also cause your AC to run nonstop. Dead batteries, electrical shorts and incorrect settings can all keep the unit stuck on when the house is already cool.
If the thermostat appears to be sending a signal to the AC to remain active regardless of indoor temperature, it probably has a mechanical problem. Change dead batteries right away and see if it makes a difference. If so, you’ll need a trained HVAC technician to install a new thermostat.
An Undersized AC Unit
Another potential reason a new AC system never turns off is that it was improperly sized. An undersized unit won’t have the power to keep up on hot days. It will run continuously trying to cool the home, but the low capacity means it never quite gets there, unable to reach the set temperature.
Installation professionals, like MT Pleasant HVAC, properly size your AC based on square footage, climate, window area, and more. You should find a “tonnage” tag on your outdoor condenser indicating its cooling capacity. Now compare that to the size guidelines for your home. If it is smaller, upgrades are needed to stop the constant running.
The System is Too Old
AC units generally last 10-15 years but regular maintenance can prolong their life span. However, after your system has passed that 15-year threshold, repairs often aren’t worth it anymore. If your AC is ancient and you’ve realized it runs around-the-clock, age-related malfunctions are most likely the problem.
Natural wear and tear on components such as the compressor, evaporator coil, and condenser will eventually result in failure, leading to the AC running constantly to meet demand. There comes a moment when purchasing a new, energy-efficient AC pays itself ten times better than continuing to spend money on an outdated unit.
The Ductwork Needs Sealing
Leaky ductwork lets cooled air escape before it can enter your home. So this causes the AC to run longer to make up for the missing air. Sealing duct leaks and insulation gaps allows your system to operate more efficiently.
Some indications of leaky ducts are dust buildup around the vents, humidity levels that feel too high, utility bills that are much higher than those of your neighbors, and rooms that are hard to keep cool. Professional duct sealing services will be able to notice and correct these issues, preventing your AC from working extra hours.
You Need a Larger Return Vent
And just like your supply vents circulate cooled air throughout your home, the return vent pulls warmer air back to the AC unit. If you have a return vent that is too small, your AC will struggle to keep up with cooling demands. The system will operate continuously, attempting to exhaust hot air quicker than the minuscule return allows.
You might also want to upsize your return vent and return filter change, which makes your air conditioner run as it should. It draws more hot air back to the unit, so it doesn’t have to run constantly, just trying to circulate air. Proper return size along with the airflow not being obstructed will help mitigate the negative running.
When to Call in Pro HVAC Service
If you have ruled out common problems like dirty filters, thermostat problems and leaky ducts, but your AC won’t stop running, it’s time to call the pros.
MT Pleasant HVAC technicians with years of experience can tell you – there have been more than a few AC units that just don’t want to shut off. We’ll do comprehensive diagnostics to determine exactly why your system is misbehaving.
Upon finding the cause (of the malfunctioning), expect our professional repairs to restore your AC as soon as possible.
From your AC installations to tune-ups, repairs and everything in between, we’ve got you covered. Count on our cooling specialists to keep your home comfortable this summer and in the future. To schedule service, call (843-936-0137). Stay cool with a running and energy efficient AC from MT Pleasant HVAC services!