What Black Creek did in 2017, and what your outdoor unit should learn from it

The storm that set the mark

Hurricane Irma crossed the state in September 2017 as a wide, slow rainmaker. In Clay County its rain fell on ground already soaked by a wet summer, and Black Creek, which drains a huge swath of the county into the St. Johns, had nowhere to put it. The creek crested at Middleburg at 28.5 feet, several feet above the previous record. Water entered more than 850 homes along the North and South Forks and their branches, and more than 300 people were taken out by boat.

The homes closest to the channel were the obvious victims. The surprise was how far the water reached up the drainage branches and across low ground that nobody considered flood-prone. Equipment that had never been wet sat in brown water for days.

Reading your own lot

You do not need a surveyor to understand your exposure. Four things tell most of the story:

1. Distance and height from the nearest drainage. Not just the creek. The ditches, branches and retention areas that feed it carry water uphill from the channel in a flood.
2. The 2017 mark. On a fence, a shed, a foundation, a neighbor’s memory. If water stood on your lot in 2017, it will again.
3. Where the outdoor unit sits relative to the lowest point of the yard. Builders tuck condensers along a side wall, which is often the drainage path.
4. Where the air handler sits. Garage floor, utility room floor, closet or attic. Floor-level equipment in a house that took water is a total loss; attic equipment is not.

Write down what you find. It becomes the specification for any replacement.

What water does, and the trap it sets

A flooded outdoor unit fails in two ways. The visible way is immediate: the fan motor seizes, the compressor shorts, the unit is dead. The invisible way is the one that costs more. The unit drains, dries and starts. The owner is relieved. Inside the cabinet, silt has settled in the fan motor bearings and across the contactor and capacitor terminals, the compressor’s electrical connections have begun to corrode, and the insulation on the low-voltage wiring has wicked up water. The failure arrives in the following summer’s heat, when demand is highest, and nobody connects it to the storm.

Every unit that stood in water should be opened, inspected, cleaned and electrically tested before the next cooling season, and the findings written down, running or not.

Call 866-266-5709

Elevation standards we use

When a replacement goes in on a lot with flood history, we build to the water, not to the brochure:

• Outdoor unit on a stand or platform set above the highest water the lot has recorded, with margin. On some Middleburg streets that is a standard pad; on others it is a stand two to three feet tall. Stands are anchored and leveled, and the unit is strapped for wind as well.
• Disconnect and whip mounted higher than the unit, so the electrical is the last thing the water reaches.
• Refrigerant lines run up the stand in a chase, insulated and protected from the sun.
• Air handler on a raised platform, or relocated to the attic, if the original location flooded.
• Condensate drain rerouted if the old discharge point is now below the raised unit.
• Surge protection at the disconnect, because the same storms that bring water bring lightning.

Before, during and after

Before a named storm: - Once the storm is close, kill the system at both the thermostat and the breaker, so a surge or a submerged start cannot damage it. - Clear the yard around the outdoor unit; debris that floats comes to rest against the cabinet. - Photograph the equipment and the data plates for insurance.

During: - Leave it off. A heat pump started with water in the cabinet is a heat pump that fails later.

After the water recedes: - Do not turn the outdoor unit on until it has been inspected, even if it looks dry. - Note the high-water mark on the cabinet before rain washes it away; photograph it. - Check the air handler and the duct. Water in a garage air handler or in under-floor duct of a manufactured home means mold within days. - Call. We open the cabinet, document what is inside, and tell you whether it is a cleaning, a repair or a replacement, with the photographs your insurer will want.

Generators and restarting

Many Middleburg households ran generators for days after Irma. A central system is the largest load in the house, and starting it on a generator that is too small damages the compressor and the generator both. If a generator is part of your storm plan, we will tell you whether your system can start on it and, where it cannot, what a soft-start kit or a different transfer arrangement would change.

The creek will rise again

Not every year, and probably not to 28.5 feet soon, but Black Creek floods, and the drainage branches that feed it reach streets that do not think of themselves as creek-side; the low ground at Doctors Inlet, between Middleburg and Orange Park, belongs on that list too. The homes that came out of 2017 cheapest were the ones with equipment already up out of the water and electrical already high on the wall. That is the whole lesson, and it is cheap to apply before the next storm has a name.