Leaving AC on....

NYSail

NYSail

.
Jan 6, 2006
3,178
Beneteau 423 Mt. Sinai, NY
While walking the bock I see boats, both power and sail that leave the AC on all the time. This is obviously a good thing to deal with humidity and the eventual mold during the hot months of summer. So this week I figured I would try the practice being now I have AC. First I put the system on the dehumidifier mode....... came back a day later and cabin was warm. Not sure if I have to change the settings on the unit but didn't have the time to mess with it so I switched to AC and turn temp up a bit and left.
I don't want to wear the units out but the feeling of a nice cool boat with no humidity is nice..... Typically we don't even turn it on. Usually come down Friday Afternoon, open all ports and hatches, put stuff away and leave. Boat vents nicely and is fine, though humidity and mold slowly return. Wife is very diligent with cleaning but figured if this would alleviate the humidity/mold problem without hurting the AC, why not.
 
Don S/V ILLusion

Don S/V ILLusion

.
Sep 25, 2008
7,687
Alden 50 Sarasota, Florida
A hose clamp(s) letting go can sink the boat --- is the usual caution. So can any clamp on an open seacock. Like is full of risks. That's why people buy insurance.

Here in Florida, virtually everyone keeps the A/C on all the time in summer and nobody's boat sank yet. When we lived in New England, we rarely kept it on while away but here, it is different.
 
Whatfiero1

Whatfiero1

.
Mar 29, 2017
576
Hunter 30t 9805 littlecreek
There is a beautiful Beni 393 in the slip next to me. The boat has never moved nor have I ever seen owner but every spring the boat starts pumping when ac comes on
 
seadaddler

seadaddler

.
Dec 19, 2006
5,832
Hunter 36 Punta Gorda
I keep the Humidiefer on 24/7 and when I know We going out boating I turn AC on a
head of time and I have added a small portable dehumidiefer when I leave Florida I keep both
on while I am up here on LI during July & August and part of Sept.
No more mold or slim on the inside.
 
Gunni

Gunni

.
Mar 16, 2010
5,937
Beneteau 411 Oceanis Annapolis
The dehumidifier setting is not designed to cool the boat, just condense moisture out of the cabin air. The A/C compressor comes on for some period of time (adjustable) chills the evaporator and then circulates air across it where moisture can precipitate to the drain pan. The setting is much less energy intensive than keeping a boat cooling for days when no one is aboard.
 
B

Benny17441

.
May 24, 2004
7,213
CC 30 South Florida
There is a direct relationship between power consumption and wear and tear so use the dehumidifier setting not so much to conserve power as you may not directly pay for it but to hopefully elongate the useful life of the unit while keeping humidity at bay.
 
kloudie1

kloudie1

.
Nov 6, 2006
10,209
Hunter 34 Mandeville Louisiana
My AC stays in "dehumidify" cycle when we are not there.. I check the hoses and clamps and fittings carefully every spring.. to avoid that sinking feeling.. It doesn't cool the boat but it does run enough to keep it dry and mildew free.. has been OK for 27 years so far.
EDIT: The other thing to be very careful with is the shore power connector at the boat end of the cord and inside the boat.. Any heat in that area while the AC is running is a cause for alarm.. fix the bad connection there..
 
Last edited:
JamesG161

JamesG161

SBO Weather and Forecasting Forum Jim & John
Feb 14, 2014
8,019
Hunter 430 Waveland, MS
I keep my brand new AC on setting of 80° all the summer and 68° in winter. Orders from the Admiral after WE had to wipe down whole cabin to kill mildew.
_____
The key to comfort when we work on boat at berth, is Low Humidity and moving Air even at 80°
Jim...

PS: The Fan on my new AC runs 24/7, compressor runs as needed.
 
NYSail

NYSail

.
Jan 6, 2006
3,178
Beneteau 423 Mt. Sinai, NY
Thanks guys.... good to know about humidity mode.... I thought it would cool a bit but now I know better!

Thanks as always for the input!!
 
BigEasy

BigEasy

.
Jun 21, 2004
3,113
Beneteau 343 Slidell, LA
I have the dehumidify cycle set for 30 minutes on, every 12 hours and run it in that mode most of the year. This time of year its so damned hot that I set the AC thermostat at 80, as does James. Nice to go into the cabin and it not be sweltering. At 80 degrees, it helps with the refrigerator not running as much and the beer is colder!
 
  • Like
Likes: NYSail
M

MitchM

.
Jan 20, 2005
1,031
Nauticat 321 pilothouse 32 Erie PA
the first year we installed the cruise air with dehumidify cycle, we forgot to boast about it to our dock mates. while up the the san juans on a vacation, we got a series of panic phone calls that our boat must be sinking because "your bilge pump is constantly pumping water out !"
 
You must log in or register to reply here.

Top Bottom