How Far from the Sea Do HVAC Coils Need Corrosion Protection?
Key facts
| Distance from the sea | Starting category | Coating |
|---|---|---|
| < 500 m | C5 | Required |
| 0.5–5 km | C4 | Required |
| > 5 km | C3 | Recommended where humid or near industry |
Why distance is only the first filter
Salt aerosol is heaviest near the shoreline and falls off inland, but the rate depends on wind, terrain and the height of the equipment. A rooftop unit 3 km inland facing an onshore wind can collect more salt than a ground-level unit 1 km away behind buildings.
What moves a site up
- Prevailing onshore winds and open exposure to the sea
- High humidity, which keeps salt deposits wet
- Industry, ports or heavy traffic nearby
- Storms and typhoons that carry spray inland
What moves a site down
- Buildings or terrain between the unit and the sea
- A dry climate with little condensation
- Installation under a roof or screen
What this means for your project
Use the distance bands to start, then adjust with local knowledge. The corrosivity estimator applies these adjustments and shows how it reached its result.
Technically reviewed byPelagard Technical TeamCoating selection, application and quality controlLast reviewed:
