Reverse cycle: Marine Air Conditioning Definition
A unit that can run backwards to heat the cabin, taking warmth from the seawater instead of dumping heat into it.
Reverse cycle in a Boat Air Conditioning System
Nearly every marine unit sold in Australia is reverse cycle, and it is very efficient — roughly 3 kW of heat for 1 kW of electricity in 12 °C water. Output falls away below about 7 °C seawater, which is the point at which a diesel heater becomes the better tool. South of Sydney, the heating is often the better half of the reason to fit a system at all.
Using Reverse cycle Specifications in Quotes and Manuals
Use this definition to understand a quote, manual or fault report—not as an instruction to modify the boat. Before buying, compare the wording against the current manufacturer documentation. For refrigerant, fixed 240 V wiring or below-waterline work, use the official licensing and standards sources and an appropriately qualified tradesperson.
Start with the complete system guide for context, or check the owner questions for plain-language answers. Technical information can change or be wrong; the disclaimer explains the limits.