Marine Air Conditioning Seawater Loop Planning
The short answer
Work out where a new skin fitting can go below the waterline, where a strainer can sit high enough to be opened but low enough to stay primed, and where the pump can live below the waterline. Everything else — unit position, ducting, drain — follows from those three points.
Boat AC Seawater Loop Planning — Requirements and Limitations
The pump is the constraint people miss. Centrifugal seawater pumps do not self-prime, so the pump must sit below the waterline or it will spin happily and move nothing. That single requirement often decides where the unit can go.
The strainer must be somewhere you will actually open monthly in summer. A strainer behind a panel that needs tools is a strainer nobody checks, and a blocked strainer is the commonest cause of a warm cabin in this country.
Related Sizing, Installation and Service Guides
Each of these answers a different part of the same problem.
- the seawater loop, drawnthe cutaway, with all six components
- what happens when it is wrongthe fault a bad layout guarantees
- the job it has to make easydesign for the maintenance, not the install
- the through-hull linewhat a proper one costs, and why teeing in is wrong