We continue to be frequently asked whether we have air conditioning aboard Sea Gem. There is good reason why South Florida was not developed prior to the invention of air conditioning--it would be uninhabitable during the summer without it. We both feel that the heat and humidity of Miami summers is greatly overrated. It was much more uncomfortable in Kentucky during the summer, for example. But we sure had air conditioning in Kentucky, and we knew that we'd need to have it on our boat in order to make living aboard a possibility.
To be sure, not every boat down here has air conditioning. If you are
using your boat only as a boat, there isn't much need for it, even
during the summer. At sea, there is usually a nice breeze, and we can
just open up the hatches and turn on the fans in order to be pretty comfortable
down below (as long as we don't run the engines too long, as they put
out considerable heat). But, at the dock, there really isn't much of a
breeze, and air conditioning is a necessity. I suspect that every boat
used as a marina liveaboard down here has air conditioning.
We actually have two air conditioners. They work great and can cool
down the boat in no time. They are controlled by modern thermostats
that cycle the air conditioners and automatically adjust the fan speed
based on the temperature that you select. Here is one of the controls:
As you can see, the A/C could hardly be easier to use. It also has a reverse cycle so that, on the few winter nights that it is needed, it can heat the boat (we haven't had anything close to an opportunity to try using the heater so far).
The only noticeable difference between our A/C and a house A/C is that, instead of having a massive, fan-driven heat exchanger that goes outside (which would look unsightly and compromise function on a boat), our heat exchanger works by sucking up water from the ocean, running it by the heat exchanger, and then spitting the now-hotter water out the sides of the boat back into the ocean. The result is that, whenever our A/C is running, we have water pouring out the sides of the boat near the waterline (you have to look for it to notice it). In addition, we need to periodically clean the water filter where the ocean water is sucked into the boat. If we wait too long and it gets clogged, the A/C will stop working and give us an error message (this has happened twice already). This is what the water filter looks like (it is in the engine/mechanical room, so we don't have to look at it unless we need to):
In the end, our boat stays dry and cool, even when summer is at is worst, and we stay as comfortable as in any other air-conditioned environment.