Den Appliances How to Protect Your Aircon from Salt Air and Corrosion
Living near the sea is hard on aircons. Here's what salt air does to an outdoor unit, the warning signs, and how to make a coastal aircon last longer.
In homes close to the sea, such as on the Atlantic Seaboard, around False Bay, in Hout Bay and Noordhoek, in Hermanus, and along the Gqeberha beachfront, outdoor aircon units can deteriorate much faster than they would inland. The good news is that most of that damage can be slowed down with the right placement and maintenance.
| Warning sign | What it usually means |
|---|---|
| White or green crust on the outdoor coil fins | Salt build-up and corrosion starting |
| Fins crumbling when touched | Advanced corrosion of the aluminium fins |
| Cooling getting weaker each summer | Reduced airflow through a blocked or corroded coil |
| Rust on the casing, screws or bracket | Corrosion of steel parts; the bracket may weaken |
| Error codes or the unit cutting out | Corroded sensors, terminals or outdoor control board |
| Refrigerant leaks | Corrosion has eaten through the copper pipe or coil |
What Salt Air Does to an Aircon
The outdoor unit pulls large volumes of air across its coil. Near the sea, that air carries fine salt particles that stick to the fins. Salt attracts moisture, and the combination speeds up corrosion of the aluminium fins and copper tubing.
First, airflow drops, so the unit works harder and uses more electricity. Next, the fins start breaking down. Eventually corrosion can cause refrigerant leaks or damage the outdoor electronics, which is when repairs become expensive.
How to Make a Coastal Aircon Last Longer
- Service every six months. A professional clean removes salt deposits from the coil and checks the electrical connections for corrosion.
- Rinse between services. With the power switched off at the isolator, gently rinse the outdoor coil with fresh water from a garden hose on a low setting. Never use a pressure washer, which bends the fins.
- Choose the right position. On new installs, place the outdoor unit on the side of the building facing away from the sea, or in a spot sheltered from direct sea spray and the prevailing wind.
- Specify coated coils. Many brands offer outdoor units with anti-corrosion coated fins, often described as "blue fin" or "gold fin". They cost a little more but last noticeably longer at the coast.
- Use corrosion-resistant brackets and fixings. Stainless steel or properly coated brackets and screws hold up much better than plain steel.
- Keep the drain and pipe insulation in good condition. Damaged insulation lets moisture and salt reach the copper pipes.
Repair or Replace a Corroded Aircon?
If corrosion is limited to the surface, a deep clean and service can restore performance. If the coil fins are crumbling, the coil is leaking, or the outdoor control board is corroded, a repair may not last long. On older units, replacing it with a new inverter unit with a coated coil is often better value, especially if the old unit uses the outdated R22 gas.
See our aircon installation service for coastal installs.
When to call a technician
- You can see crust, rust or crumbling fins on the outdoor unit
- Cooling has dropped noticeably since last summer
- The unit shows error codes or cuts out on hot days
- It hasn't been serviced in the last six months and you're close to the sea
Call or WhatsApp 064 067 4863 with the make and model, the symptoms, any error code and your suburb. More than 10 years' experience across Cape Town and Gqeberha.
FAQs
How often should an aircon near the sea be serviced?
At least every six months. Units right on the beachfront or facing the sea may need a service every three to four months.
Can I wash my aircon outdoor unit with a hose?
Yes, with care. Switch the power off at the isolator first, then rinse the coil gently with fresh water on a low setting. Never use a pressure washer, and don't spray the electrical cover.
What is a blue fin or gold fin aircon?
It's an outdoor unit with a protective anti-corrosion coating on the coil fins. It resists salt corrosion better than an uncoated coil and is a good choice for coastal homes.
Where should the outdoor unit go in a coastal home?
On the side of the building sheltered from direct sea spray and the prevailing wind, with space around it for airflow and servicing. Body corporate rules may also limit where it can go.
Book a repair or request a quote
Call or WhatsApp with your appliance type, make and model, the fault or error code, and your suburb. More than 10 years' experience across Cape Town and Gqeberha.