The wake of Hurricane Irma and Harvey left thousands of residential air conditioning systems flooded throughout regions of Florida, Georgia and southern Texas and Louisiana.
Now, hundreds of HVAC service companies are facing decisions of restoring or replacing those air conditioning units. Not all properties have flood insurance. Therefore, many property owners are faced with prioritizing repairs on a very limited budget or even through charity and government assistance.
Flooded A/C units don’t always mean replacement, because there are various degrees of damage. If a service tech has a chance to save a mildly-damaged unit or simply replace a component, it might be a tremendous benefit for a flood-ravaged homeowner already facing tens of thousands of dollars in other residential construction material replacement costs. A quick fix with the strategy of later replacing the unit could also be beneficial to homeowners attempting expedite the drying out a flooded home’s interiors.
Therefore, the following is a service tech guide with tips for determining whether or not to salvage a flooded unit. Obviously, the floodwaters must have receded, power must be restored to the home, and all electric to the unit shut off.
A condenser damaged by 10-inches or less of floodwater is a good restoration candidate, because the electrical components probably weren’t submerged. If only the bottom of the condensing coil was submerged, rinsing initial flooding residual, followed by applying a non-acid, foaming coil cleaner, will restore its thermal transfer capabilities. The foaming action is important for lifting any adhered flooding residue. Rinsing the coil thoroughly afterward is critical for coil longevity as residual chemical could potentially corrode the fins or tubing over the long term. Typically these cleaners can clean and brighten any condenser coil in five minutes. High pressure washers shouldn’t be used, because they can potentially bend condenser coil fins leading to other problems.
Condensers submerged in more than 10 inches of water will require inspection and replacement considerations, because the electrical components, the compressor terminals, and possibly the fan motor could be beyond repair. For the condenser fan motor, first “ohm it out” and check for continuity to electrical ground.
Condenser fan motors may need replacement. However, depending on the flooding severity and duration, motor windings could be dried with a quick-drying degreaser spray designed specifically for cleaning electrical contacts with no danger of shorting out components. Open motors can be sprayed directly. Sealed motors can be sprayed directly into drain ports. Fan assembly bearings are typically sealed. However, units 20 years or older may have non-sealed bearings needing definite replacement.
Electrical contacts and terminals can be subject to poor conductivity or corrosion after flooding. Therefore, another safeguard is cleaning with an electrical contact degreaser spray and/or a brush, followed by a copper flake/petroleum oil paste that brushes on for long-term protection from corrosion. Likewise, outdoor electrical disconnect boxes require drying, cleaning and corrosion protection as well. It is also an opportune time to tighten all unit terminal connections.
A condenser with a flooded circuit board or a closed relay will definitely need replacement. They’re not worth salvaging, because they could fail prematurely, which can then damage other components.
Indoor Air Handlers—Gas Fired
A gas-fired furnace subjected to flooding should be totally replaced and not salvaged, especially if any electrical, gas or safety controls were submerged. Possibly, the blower or blower motor could be refurbished as discussed in the above outdoor condenser section. However, the laborious replacement or refurbishment of the controls and the heat exchanger could surpass the cost of a new unit. Furthermore, it’s not worth the dangers or liabilities of attempting to refurbish a flooded gas-fired air handler and its safety devices that could fail later with fatal consequences.
Indoor Air Handlers—Electric
Flooded electric indoor air handlers have potential for cleanup and refurbishment versus their gas-fired counterparts. The evaporator coil should be cleaned with an indoor coil cleaner that’s environmentally-friendly and non-toxic so that any unrinsed residual won’t affect IAQ. In some cases the coil may need to be removed and cleaned depending on accessibility. A submerged indoor coil that has not been thoroughly cleaned and rinsed should not be used in occupied spaces.
Some blower motors can be dried and cleaned in a similar fashion and restrictions outlined in the aforementioned condenser motor section.
Any flooded ductwork, especially with internal insulation, needs replacement. In an age when mold inhalation dangers have been exposed, it’s not worth the cost savings of cleaning it, because newly spawned mold can hide in seams and crevices not to mention many of the other nasty contaminants found in flood waters. This is critically important for return air ducts that connect to the bottom of a closet air handler through a wooden return platform, the latter which also needs replacement.
If the air handler doesn’t already have a UV light, now is the time to put it in. It will keep the evaporator coil and interior encasement free of mold, but also disinfect airborne mold spores spawned by the flooded home interiors.
If the system is used to dehumidify the home, don’t lower the temperature below 70°F, especially if nighttime temperatures drop below the indoor set point, because the refrigerant pressures could drop low enough to freeze the coil.
Before work ensues, the service tech should establish a strategy with the homeowner. Either the goal is a short term, less expensive, quick fix to get the unit running with the knowledge of compromised longevity, or the goal is a long term solution of total or partial replacement.
Bio: James Bowman is the national technical manager–HVACR at RectorSeal, LLC, (www.rectorseal.com), Houston, which manufacturers Renewz™ condenser and Clean-N-Safe™ evaporator coil cleaners; ZIPP II™ environmentally-friendly electrical component cleaner spray; Copper-Rich™ anti-seize and copper contact protector—all available from HVAC wholesale distributors. Bowman is a former service tech for several HVACR service contractors where he’s had several experiences with flooded A/C units. He is EPA-certified, NATE-certified, holds a Class A contractor license in Texas. Bowman is available for presentations to association chapter meetings and large contractors. Bowman can be reached at firstname.lastname@example.org.