Protecting Your AC from Salt Air on the Coastal Bend

What salt does to an air conditioner

An outdoor condenser is a big radiator: thin aluminum fins wrapped around copper or aluminum tubing, with a fan pulling air through. Salt carried on sea breezes settles on the fins and holds moisture. Over time:

• Fins corrode, turn white and powdery, and crumble, so the coil sheds less heat.
• Where aluminum fins touch copper tubing, the two metals corrode faster together.
• Tubing develops pinholes and leaks refrigerant.
• Cabinet panels, screws and the base rust.
• Electrical terminals and contactors corrode and fail.

The closer you are to the Gulf or the bay, and the more directly the unit faces the wind off the water, the faster this happens. Units on Padre Island, in Port Aransas, along Ocean Drive and in Flour Bluff take the worst of it.

How to rinse an outdoor coil

1. Turn the system off at the thermostat, then switch off the disconnect next to the outdoor unit or the breaker.
2. Clear leaves, grass and debris from around and on top of the unit.
3. With a garden hose on a gentle spray, rinse the fins from top to bottom. If you can safely reach inside from the top without removing panels, rinsing from inside out pushes dirt out the way it came in.
4. Never use a pressure washer, which flattens fins, or harsh chemicals unless they are made for coils.
5. Let it dry for a few minutes, then restore power.

Near the water, doing this every month or two, and after any storm that brings spray inland, makes a real difference. ENERGY STAR lists keeping the outdoor unit clean as basic maintenance everywhere (ENERGY STAR, HVAC Maintenance Checklist).

Other ways to slow corrosion

• Placement: when installing or relocating, the side of the house sheltered from the prevailing wind off the water helps.
• Clearance: keep at least two feet around the unit for airflow, but a fence or shrub line a few feet upwind can block some spray.
• Professional coil cleaning during annual maintenance, with a coil cleaner made for the purpose.
• Electrical checks: corroded terminals and contactors are common failure points near the coast.

Coastal equipment options

When replacing a system near salt water, ask about:

• Factory or applied coil coatings that protect fins and tubing.
• Corrosion-resistant coil designs that avoid mixing metals.
• Coated or stainless hardware and cabinets.
• Whether the manufacturer's warranty has any coastal conditions or exclusions.

Related services

• AC Maintenance & Tune-Ups: Spring and fall tune-ups, coil cleaning, condensate drain care and salt-air rinsing.
• AC Installation & Replacement: New central air, full system replacement, sizing, SEER2 efficiency and the new refrigerants.
• AC Repair: Warm air, no cooling, frozen coils, water leaks, noisy units and systems that run without catching up.

Sources: ENERGY STAR, HVAC Maintenance Checklist.