On Sun, 18 Jun 2006 23:00:52 GMT, "MarshallE"
wrote:

I hear that some of the commercial boats use a residential unit and mount on
top of cabin with better success than marine grade heat pumps.

What brands are best for marine grade? Is this a project that the average
boat owner can handle?

The cost to go with a residential is much less but I am concerned that the
marine products would be better.

thanks for help,
marshall

Hi,

The biggest problem would be galvanic corrosion within the condenser's
aluminium fins and copper tubes from salt spray and salt/humidity
laden air. Similarly the evaporator from salt in the air and condensed
water.

Ways to minimise this would be having a louvred cover for the
condenser, and spraying the condenser/evaporator fins with a thin coat
of cold galvanizing spray, then a corrosion inhibitor like boeshied
etc.

Also if the condenser is on rubber mounts, the connecting pipes need a
bit of care so they don't work harden and break from vibration and
movement. Flexible pipes of the right type for the refrigerant might
be a better way to go.

Try asking on alt.hvac (don flame suit first!)

cheers,
Pete.