temperture control

[sassy]

I have a 1999 356 aft cabin and would like any suggestions on how to reduce the heat build up in the cabin during the week when not at the boat. My AC control does not allow a dehumidifying setting. I'm thinking of installing insulating/blackout curtains. Has anyone had success on this topic and if so what is the solution?

[km1125]

If you do the curtains thing, think about adding a "space blanket" lining in the curtain. Dark curtains can help but a space blanket reflects 100% of the IR. If you have canvas over your windows that would be the best place to put it because it would keep all the heat outside the boat.

The generic space blanket is a very thin plastic film with very thin reflective mylar on each side, also used as a survival blanket. You can buy them very inexpensively:
https://www.amazon.com/ANMEILU-Emergency-Blankets-Survival-%EF%BC%8CMarathons/dp/B07GLCYR5S/ref=sr_1_2?dchild=1&keywords=space+blanket&qid=1609615190&sr=8-2

[Midnightsun]

There is no secret to boats, no insulation and basically a greenhouse, even ventilation has really no big effect. Why not just leave the AC on but set it to 80f or so. When you get to the boat at least it’s not 100+f in there. Personally I leave the AC on all summer long with it turned up to keep things reasonable on board and then crank it back down to comfortable room temp levels when we arrive.

[bud37]

Welcome to the forum.....Light colored exterior window shades will drop the temps dramatically. Solar powered vents on hatches etc. Get an IR temp gun and you will see the greatest offenders when it comes to radiant heat.

[tomschauer]

Unless you are under a covered shed to keep the sun off of the boat, which will help a good bit, there is not much you can do. It is a terrarium.
As Hans mentioned you can keep the a/c on when your away but that is a personal preference. It uses a lot of juice and a lot of run hours on the A/C.
I personally want to save those run hours for when we are on the boat.

[rcoff512]

We had a local window tint company tint the inside of all windows and doors (except windshield of pilot house of course) it made a dramatic difference. It also makes the A/C work less to maintain when we are there.

Rich

[Viper]

I like the space blanket in the curtains, and tint ideas. Some boaters also use external canvas window covers for this reason. There is also a snap on mesh product that allows you to see through but helps block most rays from hitting the glass. I have both on my windshield. The mesh snaps on to the window and the canvas cover snaps on to the mesh. When we want more light, we simply remove the canvas covering and leave the mesh in place. Any canvas guy/gal can fabricate these. Don't know the selection of colours available but darker colours absorb heat while white reflects more.

Personally I'm not a big fan of leaving AC units running while away from the boat, I've been called to too many failures that caused floodings and near sinkings as a result. Most of us would never think of leaving the dockside water turned on while we're away for this very reason, leaving the AC on is no different. If you're lucky enough not to sink, depending on the location of the failure, repairing water damage to cabinetry and its brightwork can be a huge and expensive undertaking also.

[sassy]

Thanks everyone for your suggestions. I have a IR temp gun and will check temps. Thinking of adding the space lining material to the front window cover and making like curtains for the sides and cabin door. will let you know of results as the summer progresses.

[g36]

I made my windshield covers for my 405 myself, pretty easy really. I have the same set up that Viper mentioned above. I used Phifertex mesh material and put double snaps on it for the sunbrella canvas when needed. So i can leave the mesh on and snap the canvas on to it without removing. What ever you do will be a vast improvement.

[Vector4]

Do you guys leave your AC seacock open when away from the boat? Just curious, I wonder if you could set up some sort of wifi device to turn the AC on right before you arrive, but you'd have to have the seacock open.

And just FYI my boat almost sank 3 days after I closed on it because the AC seacock lid bolt stripped out and burst open. So I'm veryyyyy familiar with the dangers! Nothing like a phone call when you are 5hr away that your hull is nose down.