Leave A/C running when away?

[Mako]

Dehumidifiers with Aircon?

Oops, title should read "... without Aircon"

Since so many of you dock in hot humid summer environments (especially Gulf Coast), I was wondering if anyone relies on dehumidifying without having aircon onboard, and how adequate you find it.

Reason I'm asking is that I just returned to my villa from vacation and slept all night in my bedroom with the aircon unit on "dehumidify" instead of "cooling" mode. This was an accident since I got home at 1am.

So the temperature in the room was in the solid 90's all night, humidity about 50%, and with a fan on it was warm but not inhumane!

My conclusion is that up to a point, humidity is a bigger concern than temperature.

 

[O C Diver]

Oops, title should read "... without Aircon"

Since so many of you dock in hot humid summer environments (especially Gulf Coast), I was wondering if anyone relies on dehumidifying without having aircon onboard, and how adequate you find it.

Reason I'm asking is that I just returned to my villa from vacation and slept all night in my bedroom with the aircon unit on "dehumidify" instead of "cooling" mode. This was an accident since I got home at 1am.

So the temperature in the room was in the solid 90's all night, humidity about 50%, and with a fan on it was warm but not inhumane!

My conclusion is that up to a point, humidity is a bigger concern than temperature.

For me, humidity is a bigger issue. That said, 80 degrees is about limit for temperature. I find a dry 78 to be comfortable during the summer.

Ted

 

[stubones99]

We put the salon and forward cabin units on Humidifier mode and it works well for us.

We just had a blocked hose this past week that I blew out with a small inflator from HD.
I like the idea of a bromide tab though!

A mild vinegar and water solution works just as well but does not risk any chorine / bromine & aluminum reaction. Once a month, 1/4 cup white vinegar and 3/4 cup water into the pan and drain line.

Works on all A/C systems.

 

[stubones99]

Relative Humidity and creature comfort

So the temperature in the room was in the solid 90's all night, humidity about 50%, and with a fan on it was warm but not inhumane!

My conclusion is that up to a point, humidity is a bigger concern than temperature.

With low humidity, you will perspire and have evaporative cooling to cool your body.

With high humidity, your sweat will stick to your skin and make you quite uncomfortable.

Anything under about 40% relative humidity, you start getting zapped with static electricity from carpets and such.

 

[FF]

"Get a dehumidifier a drain to a drain overboard."

Simplest is to set it on a sink , or the counter where it can drain into a sink.

Lash it down if you can , the wake makers know when you are not home.

 

[Mrwesson]

Heat index was 130 degrees yesterday.

 

[FF]

"So how do marinas charge for electricity in areas where A/C usage is common especially during warmer months?"


Electric meter is fairest. Power hogs pay for their own consumption.

 

[foreverunderway]

I'm also of the school that I'd never leave the boat with a seawater pump running while I'm away. No, not ever, for any reason, no matter how hot it was. But hey, it's your boat.

 

[markajh]

There are several reasons to use AC or heat all the time. One is as you mentioned - more efficient performance of a refrigerator. Another is to keep the bilges better maintained from smell and dampness. That said, anytime you are away from your boat - you want to be confident of the systems that are running. Make sure you are in your comfort zone about that.

 

[rgano]

You are more likely in jeopardy of having a stinking refrigerator from a marina power loss than any danger of flooding due to poor plumbing. And if you have an inverter connected to pick up the load when a/c power is lost, dead batteries can result as well.

My preference was to run a dehumidifier into a sink drain and have a fan or two to circulate dried air to other parts of the boat.

I was always over cautious with my wooden-hulled Grand Banks, and while I never went to the extreme of shutting off sea cocks, I considered a plumbing break on the outlet side of my air conditioners sufficient to sink the unattended boat.

I never left the generator running unattended either, except the one time I went aboard a nearby boat for a while only to hear the danged thing wind down from a fuel clog and brown out the boat. But I was generally more concerned about the possible but remote issue of the gen firing itself up in a blaze of glory.

We never left any refrigerator or freezer running when away from the boat for over a day or three, and I never installed an inverter in the boat other than small dedicated ones.

 

[jimdavi]

Last boat air ( Sea Ray)had dehumidifier mode, we used successfully when leaving the boat during the week when docked in Minnesota. Never had mildew or moisture issues. Unit ran some every hour. Yes, very humid in Minnesota during the summer.

 

[psneeld]

wonder how many are anti city water hookup, but leave their A/C running while gone...

 

[NightCrawler]

We leave a dehumidifier in the shower. We're never gone more than a week, so even if the shower sump failed, it would hold the water. At the store, I had the clerk bring power to the display and plug each one I was interested in with the cord. Then checked to see if it would restart after unplugging it. Some will, some won't.

 

[Mako]

I’m really liking the idea of just running dehumidifiers when away from the Boat instead of aircon, especially if it will be for months at a time. It’s not just the simplicity of a “plug and play” Home Depot unit without the complexities of marine air, but also the lower power consumption. A dehumidifier on a timer can easily be run off solar panels for those not plugged into shore power.

 

[FF]

If the purpose of the Dehumidifier is to cut down on mold and mildew , this can also be done chemically with no energy bill..

On metered electric $50. per month might be the price of a clean interior.

That could be $300 per summer , UGH!

 

[sbu22]

I don't run the A/C when we're off the boat. No dehumidifier either. A carpet dryer blower runs full time to circulate air through the boat. Set in V berth to direct air flow aft. Engine room and forward deck plates open to allow limited air circulation to bilge. Zero mold/mildew problems in 8 years. Reefer does just fine. Yes the interior is hotter than the hinges of hell on my arrival. Takes about 10 minutes to cool things down to tolerable after A/C start. Full time A/C power cost about $100/month. Good trade, I think. This is in New Orleans.

 

[ABfish]

I leave the Cruisair units on my boat in dehumidify mode.

In HU mode, they run for 30 minutes every 12 hours. The fan runs for 10 minutes at high speed during each cycle. Power consumption is relatively low, and the boat stays mold free and dry.

 

[Mako]

ABfish, so in DU mode they don’t use the same amount of energy as in aircon mode?

 

[ABfish]

ABfish, so in DU mode they don’t use the same amount of energy as in aircon mode?

The HU mode uses much less electricity. I left the A/C on for a couple of weeks, and my power bill went up by about $80. (I have two units, one in the saloon and one in the stateroom).

That's not a scientific comparison, as I did not record the actual number of days that the units ran full tilt, but my bill was noticeably higher.

When I enter the boat after a week on HU mode, the boat is hot, but the humidity is under control. I have zero mold in my bilges or shower.

Dehumidifiers are effective and may save a few bucks, but I don't want to deal with another piece of equipment to maintain and store. If I really wanted to save money, I'd sell the boat!