In South Florida's heat, your boat's air conditioning works harder than almost anywhere. Proper maintenance keeps you comfortable and prevents expensive repairs.
How Marine AC Works
Most marine AC uses raw water (seawater) cooling. Seawater circulates through a condenser, absorbing heat from refrigerant. This makes marine AC more complex than home units.
Monthly Maintenance
- Clean or replace air filter: Dirty filters reduce efficiency dramatically
- Check water flow: Verify water is discharging from through-hull
- Inspect strainer: Clean raw water strainer of debris and growth
- Check drain pan: Ensure condensate is draining properly
Seasonal Maintenance
- Clean coils: Use coil cleaner on evaporator (inside unit)
- Flush seawater system: Run fresh water or descaler through raw water circuit
- Check refrigerant: Low refrigerant = poor cooling (professional service)
- Inspect hoses and connections: Look for leaks or deterioration
- Test thermostat: Verify accurate temperature control
💡 Florida Tip
Flush raw water system with fresh water or Barnacle Buster monthly during heavy use season. Marine growth in seawater lines is the #1 cause of AC problems in Florida.
Common Problems
| Symptom | Likely Cause |
|---|---|
| Weak cooling | Dirty filter, low refrigerant, restricted water flow |
| No cooling | Compressor issue, refrigerant leak, electrical problem |
| Water leak | Clogged drain, condensate pump failure |
| Strange noise | Failing compressor, pump cavitation |
| Burning smell | Electrical issue—shut off immediately |
When to Call a Professional
- Refrigerant issues (requires certification)
- Compressor problems
- Electrical faults
- System not cooling after basic troubleshooting
Extend AC Life
- Run AC regularly, even when not aboard (prevents seal dry-out)
- Keep strainer clean
- Flush seawater system monthly
- Don't set temperature too low (increases strain)
- Ensure good airflow around unit
Find marine HVAC professionals through Boatwork for repairs and annual service.
