Regal 3300 Owner's Manual page 206

CHAPTER 6
Air Conditioning System
If installed, the air conditioning system needs an AC power source
to operate, supplied either by shore power or an onboard generator.
Never switch the air conditioning system water pump breaker ON
until after the seacock supplying the air conditioning system with
seawater has been opened. Operating the air conditioning with the
seacock closed can damage the system.
The air conditioning system produces heat when operated in reverse
cycle mode. Reverse cycle operation is affected by the temperature of
the seawater. The air conditioning system's ability to produce warm
air decreases as seawater temperature decreases. It is recommended
to avoid operating the air conditioning system in reverse cycle mode
when the seawater temperature is below 40°F (4°C).
Refer to the equipment manufacturer's manual for additional
information.
6-46
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