On and off every five minutes in an East Palatka double-wide: the short answer, then the long one

Three causes, one sentence each

Stand at the thermostat with a watch. A healthy air conditioner in Putnam County in July runs for fifteen minutes or longer and rests for a while between runs. If yours runs for three to seven minutes, stops, and starts again a few minutes later, it is short cycling. Three causes account for nearly all of it:

• Too much air conditioner for the home. It reaches the setpoint so fast that nothing else gets done.
• Something restricting it. A clogged filter, a frozen coil or a dirty outdoor coil pushes pressures out of range and trips a safety.
• An electrical or control fault. A failing capacitor, a loose low-voltage wire, a thermostat in the wrong place, or a float switch tripping on a half-clogged drain.

The first one is a sizing problem and the fix is bigger than a part. The second and third are repairs, often quick ones.

The long answer, for the homes we see most

East Palatka, Satsuma, the lake communities and the county’s rural roads hold a very large share of manufactured homes; in some ZIP codes close to half the housing. Those homes are the short-cycling capital of the county, for two reasons.

First, sizing. A package unit for a manufactured home is frequently picked from a chart by square footage rather than calculated for the home as it sits. Under a porch roof and a stand of oaks, the home’s actual cooling load is smaller than the chart assumed, and the unit is oversized from the first day. It cools the air in five minutes and quits before it has pulled any moisture out, which is why so many of these homes are cool and clammy at once.

Second, airflow. Under a manufactured home the belly duct splits and sags; the return is often a single grille in a hallway; the filter slot is small. A unit that cannot move enough air builds pressure, trips its own safeties, and cycles.

Block houses in Newtown have their own version: a hall closet handler with one undersized return, and a replacement unit that was bought a size up “to be safe” when the old one died in a heat wave.

What affects the cost of fixing it

Cheapest: a filter, a capacitor, a loose thermostat wire, a drain flush for a float switch that keeps tripping, or relocating a thermostat out of a register’s draft. These are same-visit fixes with parts on the truck.

Middle: a blower motor, a control board, a refrigerant leak search and repair, or sealing and repairing the belly duct so the unit can breathe.

Largest: the oversized unit itself. When a package unit is a full size or more too big for the home, no repair makes it run properly. The honest fix is a correctly sized replacement, often a staged or variable-speed unit that can run low and long, and we quote it with the duct repair the home also needs. Clay Electric’s rebate on a qualifying replacement heat pump can apply at many rural addresses; inside Palatka and East Palatka on FPL, the utility’s program pays through enrolled contractors, and Cook’s enrollment is a question to ask. [[CONFIRM WITH JERRY]]

Call about a short-cycling system

Scheduling, and why timing the cycles helps

When you call, tell us how long it runs and how long it rests, whether the air is cold while it runs, and whether the outdoor unit stops with the indoor fan or keeps going. Those details let the technician load the right parts before the truck leaves Palm Coast. Most short-cycling calls in Putnam County are same-day. The line never closes, and a Saturday evening visit costs what a weekday one does.

Keeping a right-sized unit running right

A system that was short cycling for a season has been starting a dozen times an hour, and starts are what wear a compressor. Once it runs properly, a maintenance visit before next May to check the charge, clean the coils and look at the ducts under the home is the cheapest insurance against doing this again.