It’s a frustrating situation. The air conditioner has been running since morning, the thermostat is set to 72 degrees, and the house is still sitting at 80. You’re not imagining it. There are several reasons an AC can run nonstop without doing its job, and some of them are easy fixes while others are signs that something more significant is going on.
The Filter Is Clogged
This is the first thing to check, and it’s the most common culprit behind poor cooling performance. A dirty air filter restricts airflow through the system. When the blower can’t pull enough air across the evaporator coil, the system can’t move enough heat out of the house. Some systems will even freeze up the coil entirely, which stops cooling almost completely and can cause water to drip inside your home.
Check your filter and replace it if it’s been more than 90 days. In a busy household with pets, monthly changes are often better.
The Outdoor Unit Is Dirty or Blocked
The condenser unit outside needs airflow to reject the heat it’s pulling out of your home. If the fins are packed with grass clippings, cottonwood fluff, or debris from nearby landscaping, it can’t do that efficiently. The system runs harder and longer while accomplishing less. Gently rinsing the condenser coils with a garden hose (from the inside out) can help, but a professional cleaning is more thorough and safer for the equipment.
Your Home Has an Air Leak Problem
Even a well-maintained AC can’t keep up if the house is leaking conditioned air out and pulling hot humid air in. Old or damaged weatherstripping around doors and windows, gaps around recessed lights and attic hatches, and poorly sealed ductwork all contribute. Duct leaks in particular are sneaky. If 20 to 30 percent of your cooled air is escaping into an unconditioned attic or basement, you’ve essentially lost a quarter of your AC’s capacity.
The System Is Low on Refrigerant
Refrigerant is what actually carries heat out of your home. When a system develops a leak and the refrigerant charge drops, it loses its ability to absorb heat from the indoor air. The result is a system that runs constantly but can’t make a dent in the indoor temperature. This isn’t something that gets fixed with a simple top-off. A technician needs to find and repair the leak before recharging the system.
The System Is the Wrong Size for Your Home
An undersized air conditioner will simply never keep up on a 90-degree day with high humidity. It wasn’t installed with enough capacity to handle the load. This can happen when additions were built onto a home without upgrading the HVAC system, or when the original installer underestimated the home’s needs.
Oversized systems have a different problem. They cycle on and off too quickly, which cools the air without removing enough moisture. The house feels clammy and uncomfortable even when the temperature reads correctly.
It Could Also Be Time for a Replacement
Air conditioners lose efficiency as they age. A 15-year-old system may be working as hard as it can while still falling short of what a newer, more efficient unit could do with less effort. If your system is aging and you’re having problems keeping up on hot days, a conversation about replacement might be worth having.
If your AC is running all day without results, don’t just let it grind away. Give McKee Brothers a call at 401-723-1100. We’ll diagnose what’s actually going on and give you a straight answer about what it will take to fix it.