Southern boats....air conditioning...

I am looking for information on what other owners do concernin running the A/C units on their boats while not on the boat. I am located in the coastal bend of Texas on the Gulf Coast.

Do you leave yours running on a higher setting, turned off completely or something entirely different? Currently I have mine on a dehumidification setting that runs each unit two hours a day at twelve hour intervals. In the weather we are currently having the internal temperature inside the boat can reach and occasionally exceed 100 degrees.

My primary concerns are issues with the cooling pumps, the through hull becoming blocked by a piece of trash or becoming clogged with grass and just overworking the compressors and causing premature failures. There is also the risk of a cooling hose rupturing and then pumping salt water into the bilge.

Looking forward to hearing from other owners.

We don't run the A/C's while we are away. I sleep better away from the boat when I know all the seacocks are closed. When we are gone we use a dehumidifier from Lowes on a timer. I have it on a counter and it drains into the kitchen sink. We also have a couple small fans in the lower cabins to circulate the air. Doesn't cool the boat, but does a great job keeping the humidity way down while we are gone, has done wonders for boat smells and keeps the mold at bay.

I've seen some boats with a 110vac portable air conditioner to keep it cool.

I don't like to leave the AC running while I'm away from the boat for the reasons you mentioned. I have a portable dehumidifier, I set the desired relative humidity and it drains into the galley sink then overboard. I have a portable AC unit, like folivier mentioned, at home it works well, I have never tried it on the boat, it seems to me it would work fine venting out through a window.

We leave ours on but turn the thermostats up.
We go there every day or couple of days to check on things.
Still thinking about getting a portable unit.

Leave mine on set at 80 degrees. Did all the installation myself to make sure all plumbing was done correctly. If I was worried about a plumbing failure sinking my boat, I wouldn't sleep on it with the AC running. The AC systems have auto shutdown protection for system failures. I do check on my boats every few days, but worry more about external stuff such as dock lines during bad weather, other boaters not being careful, and the occasional mischievous teenagers.

Ted

It depended on how long we were going to be away from the boat and how hot it was. So, sometimes in the "dehumidify" mode, sometimes set to 80 degrees. We had a Pfifertex screen for the large lower helm windows, and the side windows had an "eave" that covered the side decks which helped a lot.

I kept all my plumbing and hoses very well maintained and updated so never worried about a failure causing flooding any more than I would for any other house we ever lived in. The A/Cs shut down if not getting water delivered due to a strainer clog and in turn can be set up to turn off the pump as well, so no worries about equipment stress or failure.

dkasprzak

Do a search I started a thread a while back on this. I used up two a/c's, roof top and portable, last year trying to keep the inside of LUNASEA cool. This year I am using the old attic fan method, open vents in bow and fan blowing out in stern seems to be working.

I trun it off and open a hatch

Mostly leave it on but in our case here on mobile bay and with a shallow slip the water is pretty muddy. I have to clean out strainers and blow out the lines at least once a week especially when we have unusually low tides. I do usually set temp at around 80 though.

We leave ours own to keep humidity down and to keep temperature at a reasonable level. We do the same with our house. As to any risks, we have bilge pumps and alarms with the alarms set up to send us text messages. We also have someone checking daily where our boat is stored and there is full time security with part of their job keeping an eye on things. In addition we can always do a quick check of the boat through the web and cams on board.

BandB, what alarm system are you using for bilge pumps?

I tried the AC humidity control method, then just leaving the cabin door open to the enclosed aft deck, then a dehumidifier and lastly a cheap 12" fan with some tea tree gel in cups in a few places.


The dehumidifier and fan worked best within limited temperature ranges but the fan and tea tree gel was the easiest and always left the boat smelling good.


Very important however to have a clean dry bilge and a clean cabin to start.

We only run the ac when we are on the boat. We run several fans while off the boat and will bring on a dehumidifier once repaired.

From being in business and knowing what can happen with anything electrical when un attended. I would NEVER leave my boat electrified . and even just the 12volt system for the bilge pump is enough that something can go wrong and usually does when you least expect it.

edit;
Yes I do know sometimes we just have to Leave something on or running.

I most cases I leave at least one unit on.

If all I care about is lowering the humidity I'll use a dehumidifier set to drain overboard one way on another.

DeniseO30 said:

From being in business and knowing what can happen with anything electrical when un attended. I would NEVER leave my boat electrified . and even just the 12volt system for the bilge pump is enough that something can go wrong and usually does when you least expect it.

edit;
Yes I do know sometimes we just have to Leave something on or running.

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With that kind of fear, I'm having a hard time visualizing you living aboard let alone taking a nap on a boat. Certainly a boat's electrical systems need to be squared away and periodically checked, but were not talking tube and wire in a hundred year old house.

Ted

Ted wow, you really misunderstood me lol

folivier said:

BandB, what alarm system are you using for bilge pumps?

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Intelisea.

O C Diver said:

With that kind of fear, I'm having a hard time visualizing you living aboard let alone taking a nap on a boat. Certainly a boat's electrical systems need to be squared away and periodically checked, but were not talking tube and wire in a hundred year old house.

Ted

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I felt like you for many years. However, this past 4th while I took a quick siesta, I was awaken by breakers, AC units going off and on in rapid fashion with reverse polarity red lights blinking on the AC panel! Cutting off everything AC I eventually found a very overheated (to the point of melting) power cord plug that's attached to the boat. Lost a tv, charger and a few other items fried. If I was not onboard know telling what could have happened. So now I'm a Denise convert with new power cord, better connections and leave only my charger and refrig circuit on.

Like others here, we do not use the AC when leaving the boat during the week. We do run a small dehumidifier, which has worked great in terms of keeping the boat dry and avoiding any musty odors.

I liveaboard on the Mississippi north of St. Louis most of the year. I turn the AC off anytime I'am away from the boat. The units are large enough that 1 will cool the boat pretty quickly in the covered slip when I return.

KneeDeep said:

When we are gone we use a dehumidifier from Lowes on a timer.

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Well, I never thought of using a timer for the dehumidifier!! Duh. I hate to run one all the time, because the electric rates at my marina are exorbitant, but a timer would be perfect. Thanks for the idea.

Dehumidifiers and things like electric space heaters are made pretty well. But please, Always check the outlet and plug, they tend to heat up, GFCI can and should trip, but don't assume they will
If a boat is at a marina the assumption is someone is making at least a walk by of the boats, but again I 'd not assume.
Jus saying

you can wire a humidistat in parallel with the thermostat,thus only turning on when the humidity levels reach the set point.Humidistats don't care what the temperature is.That would cut your ac bill tremendousely.You can have days that are 90 degrees,but the humidity level is low,hence the ac wouldn't run.This prevents the odor,and mildew issue,without the expense,or the run time on the compressors.

I use a Peltier Effect dehumidifier that is about the size of a loaf of bread. It drops the humidity low enough that mildew doesn't grow. It uses very little power. I sit it next to the galley sink and run a drain hose into the sink drain.

ragin cajun said:

I felt like you for many years. However, this past 4th while I took a quick siesta, I was awaken by breakers, AC units going off and on in rapid fashion with reverse polarity red lights blinking on the AC panel! Cutting off everything AC I eventually found a very overheated (to the point of melting) power cord plug that's attached to the boat. Lost a tv, charger and a few other items fried. If I was not onboard know telling what could have happened. So now I'm a Denise convert with new power cord, better connections and leave only my charger and refrig circuit on.

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So, are you ever going to sleep on your boat again while connected to shore power? If you have rectified the cause of the problem and still fear it's reoccurrence, how could you ever feel safe sleeping on your boat again?

Ted

O C Diver said:

So, are you ever going to sleep on your boat again while connected to shore power? If you have rectified the cause of the problem and still fear it's reoccurrence, how could you ever feel safe sleeping on your boat again?

Ted

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I'd add to your question, did you have a professional marine electrician come examine your boat after the incident and make sure everything was in compliance? I know I'd sure have had to do that to sleep comfortably.

BandB said:

I'd add to your question, did you have a professional marine electrician come examine your boat after the incident and make sure everything was in compliance? I know I'd sure have had to do that to sleep comfortably.

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Great question. After finding the shore power cord shot on one end, I disconnected from shore power completely on both ends. With everything turned off I started the genny. All showed fine on the panel with correct voltage to both AC circuits. I started adding loads one by one to the genny with the 2 a/c being last. All was normal and I let everything run on genny power for over 4hours. During this time I ran to WM and purchased a brand new 50ft/50amp power cord. I'm ditching the old one; not repairing.

We slept on board for the next 2 days with no issues. Of course I selpt on the couch next to the breaker panel during that time. I checked on those connections many times during those days...cool as can be. I feel confident the very old cord had bad terminals causing the failure.

ragin cajun said:

Great question. After finding the shore power cord shot on one end, I disconnected from shore power completely on both ends. With everything turned off I started the genny. All showed fine on the panel with correct voltage to both AC circuits. I started adding loads one by one to the genny with the 2 a/c being last. All was normal and I let everything run on genny power for over 4hours. During this time I ran to WM and purchased a brand new 50ft/50amp power cord. I'm ditching the old one; not repairing.

We slept on board for the next 2 days with no issues. Of course I selpt on the couch next to the breaker panel during that time. I checked on those connections many times during those days...cool as can be. I feel confident the very old cord had bad terminals causing the failure.

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I thought it was a good question and your answer was "No, I did not." I don't see electricity as an area to be left entirely to DIY. Not in a house. Not on a boat. Odds are great you won't have a recurrence of problems, but then you didn't expect the first problem. I'd engage a professional even if all I did was pay him a couple of hours to tell me everything is great and I did just what he would have done. I know it could seem like a waste of money, just my view. I respect if you choose to ignore my advice but feel compelled to say it.