My wife and I have a newborn (8 days old!) and need to put A/C in the cabin. I'm thinking of getting a 6,000 BTU unit, which should be enough to take the bite off during the hottest summer days. I have four optima blue top d31m batteries. Will this be enough power to run the A/C for a while or do I need a generator too?

you can run a inverter to run a small a/c mermaid has a couple small unit that feature soft start compressors, but on battery still only going to get hours of run time(depends on the size of the boat and outside temp) I would look at the honda gen's on swim platform, or tie up in a marina that has power...battery deal not great

Get a small portable gen. It will be the best route in the long run

I used to have a 4D CAT battery to run the A/C. It would last about 30 mins, which was a lifesaver on certain days. Finally bought a generator, and am I am glad I did. Much, much better!

How hot does it get in Grand Rapids?

The average is around 80 for the summer months. My youngest is 9 DAYS old at this point, meaning he'll be 6 months give or take during peak boating season. I don't want to have to stay home on a gorgeous afternoon because it's too hot to hang out in the cove with a baby!!

What type of 6,000 BTU unit would you use?

I've had my eye on this unit, but haven't done as much research as I would before I make the purchase. I don't really need the cabin to be that chilled - I just want the edge taken off a bit. Open to suggestions/recommendations....

There's some good write ups in the fountain section of guys adding air to 32s iirc. I friend runs his 12k unit of a Honda 3000.

I do agree with you wanting it to be able to increase your family boating, my kids love to get out of the sun and kick back

Most summers mid 80's to 90's, but 2 or 3 summers ago it was mid to upper 90's almost every weekend. I some times cherish the AC on my cruiser.