The September bill at a Country Club Estates house came in a third higher than last year's: four readings before anyone blames the heat

What happened at the Country Club Estates house

A retired couple in Country Club Estates, in a single-story home beside the golf course, opened the September FPL bill and found it a third higher than the September before. Nothing had changed. Same thermostat setting, same two people, same pool pump schedule. The air conditioner was cooling. Their first thought was the heat; it had been a hot summer, as every summer here is. Their second was that the utility had raised rates. Their third, after a week, was to call 866-266-5709.

The bill turned out to be the air conditioner, but not for the reason they expected, and the path to finding that out is one any Lake City household can walk before picking up the phone.

Compare kilowatt-hours, not dollars

Pull last year’s bill for the same month and put it beside this one. Ignore the dollar total and find the kilowatt-hour line. Three outcomes:

• Usage is flat, dollars are up. The rate changed. FPL and Clay Electric both adjust their charges from time to time, and this is not an air conditioner problem.
• Usage is up a little, and the month was hotter. Both utilities print degree-day or temperature comparisons on the statement or in the app. If August ran several degrees hotter than last August, a modest usage increase is just weather.
• Usage is up a lot, and the weather was similar. Now something in the house is drawing more power than it did, and in a Lake City summer the air conditioner is the first suspect because it is more than half the bill.

The Country Club Estates couple were in the third group: usage up by about a third, weather within a degree of the prior year.

The causes, from most to least likely here

1. Duct leakage that got worse. Flex duct in a hot attic ages, joints pull apart, and a return leak lets the system cool the attic. A duct that lost a connection in June adds hours of run time all summer, silently. Common in the 1970s-80s stock and in any house where someone was recently in the attic.
2. A refrigerant charge that has drifted low. A slow leak does not stop the cooling at first; it makes each hour of cooling do less, so the system runs longer. The bill rises months before the house gets warm.
3. A dirty outdoor coil. Pine pollen and oak catkins from spring, matted and baked on. The condenser cannot shed heat, and every cycle runs longer.
4. Strip heat running when it should not. A failed thermostat, a stuck sequencer or a miswired heat pump can energize the electric strips during cooling. It is the single most expensive fault on this list and the hardest to notice, because the house still gets cool.
5. A failing capacitor or a compressor drawing high current. The system cools, but the compressor works harder to do it. Often the stage before a breaker trip.
6. Everything that is not the air conditioner. A water heater element, a pool pump running longer than its timer says, a well pump cycling on a leaking pressure tank out in the county, a freezer in a hot garage. These are worth ruling out before a service call.

Thirty minutes of checks you can do yourself

Take a photo of the electric meter at the same time two days running, once with the air conditioner running normally and once with the system off at the thermostat for the full day while you are out. The difference is roughly what the air conditioner costs per day; compare it to the daily average on the bill. Put a hand on the supply register nearest the air handler while the system is cooling; the air should be cold, not cool. Put a hand on the air handler cabinet; it should not be warm during cooling. Walk the attic edge with a flashlight and look for a flex duct run that has fallen or pulled off a boot. Look at the outdoor coil for a yellow-grey mat. Check the pool pump and well pump timers. Write down what you find.

At the Country Club Estates house, the register air was cold, the cabinet was cool, but the attic walk found a return duct that had separated from the air handler’s plenum behind the insulation. The system had been cooling the attic since early summer.

Have the system checked against the bill

When the meter test says call

If the meter test shows the air conditioner using far more per day than it should for the house, if the supply air is merely cool, if the cabinet is warm during cooling or if the attic walk turns up a duct problem you cannot reach, call. The visit measures what the kitchen table cannot: the system’s actual current draw against its rating, refrigerant pressures, airflow and static pressure, duct leakage with a proper test and the strip heat circuit for unintended operation. On an old system drawing high current with low charge, the visit becomes the repair-or-replace conversation, with the projected bill difference of a new high-efficiency unit written next to the repair price. Either way you leave with a number, and the next bill tells you whether we were right.