Heat waves have been putting home cooling equipment under pressure all over the United States, but Florida's soaring temperatures have been pushing even well-maintained cooling systems to their limits.

One homeowner highlighted a problem many people dread during peak summer: an air conditioner that runs all day and still can't keep the house cool.

For families watching their power bills climb, nonstop runtime can be a hefty burden, even more so when they still live in discomfort. 

What happened?

In a Reddit post, a homeowner in Florida described a two-story, 1,800-square-foot house that stayed at 81 degrees Fahrenheit during the day even though the thermostat was set to 75.

To explain the conditions, they said the weather outside was severe: 57% humidity, a temperature of 94 degrees, and a "real feel" of 108. The equipment comprised a 3-ton, 5-kilowatt air handler and a Trane condenser that uses R-410A refrigerant.

The homeowner said they had recently replaced the ductwork, along with the return and supply plenums, after finding mold and rat-related insulation damage.

Their main concern was whether the new supply plenum's shorter, offset design could limit airflow, reducing cooling performance, and possibly leading to coil issues later if the system keeps straining.

"My house doesn't get below 81 with the AC running at all times," they said. 

Why does it matter?

When an AC runs all day without reaching the set temperature, homeowners take a hit on comfort and on the utility bill.

Constant runtime typically means higher electricity use, and if airflow is restricted, the system may also face added wear that can lead to expensive service calls or a shorter equipment life span.

For those thinking about replacement instead of another repair, heat pumps are significantly more energy-efficient than traditional HVAC systems while providing both heating and cooling. That can translate into lower monthly bills, long-term savings, and access to tax credits and rebates, and homeowners can compare options through EnergySage's Heat Pump Marketplace.

For rooms that stay hotter than the rest of the house, Merino offers single-room HVAC systems. It's a targeted heating and cooling option that could offer relief in one problem area without overhauling the whole house.

An overworked cooling system can mean higher energy costs just to maintain an uncomfortable indoor temperature. In especially hot and humid regions, that kind of inefficiency can add up quickly during the summer months.

What can I do?

If your AC is running nonstop, a good first step is to ask an HVAC professional to check static pressure, airflow, refrigerant charge, duct leakage, and whether the plenum and duct design match the equipment. Catching a mismatch early may help prevent wasted energy, frozen coils, or repeat repair bills.

In hot, humid climates, attic insulation, air sealing, sun exposure, and a two-story layout can all make upper floors harder to cool.

Even if extreme weather is part of the problem, improving airflow and reducing heat gain can ease strain on the system and trim monthly energy costs.

Homeowners who are ready to offset the costs of summer cooling may also want to explore solar energy, and EnergySage offers a free solar quotes comparison tool. For anyone comparing HVAC replacement options, EnergySage's Heat Pump Marketplace can help homeowners shop more efficiently.

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