Aircon / dehumidify in the med

Andy Bav

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We have never had aircon in the past, but on our V42 we do and, as Autumn has arrived and the nights are getting longer, it would be useful to understand what other Med based forumites do over winter. Our aircon has 4 settings

1. Cool
2. Heat (!)
3. Heat / Cool
4. Dehumidify

The argument is that leaving her "off" from late October to early Feb is that there is no-one around to keep an eye on her - although I could arrange for a regular visit - but there is no hazard to the system.

The argument for leaving her "on" is that the boat could be kept at a constant temperature and as all inlets / outlets are below water level, the system will be working, fouling around inlets reduced and noise kept to a minimum

We have a couple of trips planned for Sept and Oct but I am inclined to set the system in the saloon at Heat / Cool at 20 - 22 degrees, but it would be useful to know what others do.

Electricity is "free".

Any thoughts ?
 
Andy,

On our old boat it was lock it and leave it. Nothing left on and we never had a problem. We tend to go down once a month and open the boat up then.
 
Nothing
Periodically just clean the mesh filters on the air handlers maybe 2x /year .

In the off season run it all up now and again so to minimise anthing ceasing up ,like A N other boat system .
There's a reversing valve on the AC which needs exercising prone to cease and if it does it won,t reverse cycle -ie produce heat in the winter .

Regarding the temp and winter storage which I suspect is what you are asking ?
For the past 14 years my guardiene Co who looks after loads of boats
Close all windows
Place oil heaters with thermostats in all the spaces and leave on .
These come out end of Oct early Nov and are put away April/May .

We had no issues ,no mould , damp , heading dropping -odours ,stains , - lacquer bluing on the high gloss Sunseeker wood --absolutely nowt -

So we just do the same with the Itama --- 2 winters later again none of the above .
Leccy is all in too -not a consideration .

I think the whole systems like engines , Geny ,A/con , toilet flush , black tank pump etc are periodically "run up " .
It not as if we chuck the keys end of Oct and expect it all to go in May ,boat sat there idle for 6 months .

I have a pic of snow on the Sunseeker as well even in SoF
 
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What kind if winter temps are we talking?

In Ireland what we do is run an oil filled rad & dehumidifier for about 8 hours per day (timer) which keeps the boat nice and dry...well, I've never had a mould issue so I guess it works.

We pay for electricity where we are but over the winter months the bill is approx 200 euro, so worth every penny (and more) to have a dry boat
 
turn everything off, prop all the cabin/bathroom doors open. lock up and leave.
the coastal winter weather in med Spain is very mild. The boat will be bone dry when you come back.
 
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Thanks all. I believe that coldest temps are mid single digits, and she will be in the water throughout the winter. On the Bavaria we did just leave her, but she had no aircon, and it did need a day or two "airing" when we returned purely as there had been little air circulating. I can see an opportunity to circulate air on an intermittent basis and am inclined to run the dehumid setting as Jimmy does. Hope to not leave her for more than 3 months max before we start our monthly visits ..
 
I wouldnt want to leave my A/C unit running all winter for a couple of reasons. First the electricity usage would be huge and most marinas meter that. I understand its free in your marina but I'm not sure the marina managers would appreciate your usage! Second what happens if something goes wrong with it like the seawater inlet gets blocked, shutting the unit down, or a component fries itself causing a potential fire hazard? Both have happened to me in the past

FWIW all I do is leave a dehumidifier in the galley, with a drain pipe into the sink, controlled by a plug in timer so that it comes on for an hour a day. Never had an issue with mould
 
Hi Andy,
Much prefer a passive approach. The cockpit gets vented by nature, job done; the saloon is locked with cabin & cabinet doors & bilge access hatches open with desiccant bags littering all around. Shorepower only charges batteries, so bilge pumps on alert and galvanic isolator checked to show no leakages when we depart. Only ever plugged heaters in at dry stack in UK, then only on an external service rack but also had VP out to do "winterisation", not needed in Spain thank goodness!
 
We do not leave a/c or heating running when the boat is unattended for any length of time due to the risk of failure/damage. The boat is in regular use (couple of times per week) from April to September but is not used much from October to March. "Out of season" the guardiennage company puts small portable oil fired radiators in each cabin and runs the a/c or heating up for 30-60 minutes each week when the boat is being cleaned. Never had any problems with humidity, mouldy or damp.
 
I leave both toilet windows open. If it rains, the tiny amount that gets in just goes into the shower sump. The sump is bigger than most, I'd guess about 15lts. I wouldn't leave the aircon running.
 
I leave my boat in mallorca from november to may, just leave it with the cover on, but cabin door ajar. I dont use any heaters etc,and have no issues with mould etc,but i do have a high quality breathable cover,if it was made of a non breathable fabric i suspect id have some issues
 
Hi Andy,

Having had a boat in SCM for just over nine years now, I can confirm that there is no need to leave any AC on in winter, the nights can get cold in winter, but I have never had any issues whatsoever with damp and certainly no issues with freezing. I even removed the two bar heaters that used to sit below the engines....!

When I had my boat in Torquay and Brighton, I did use to winterise it, but in SCM, I just leave all doors open, lock up and leave. I do isolate all of my seacocks as this regularly exercises them and leave my battery charger on!

With the AC I just clean the air filters on my two reverse cycle heat pumps and throw a couple of sterilising tablets into the condensate trays just to stop any significant bacterial growth but they soon dry-out anyway.
 
I don't de humidify either but I would point out that boats.co.uk de humidify all customer boats they look after and all their stock boats. I expressed surprise. They said it says a whole heap of problems so maybe we are all wrong !
 
Assume they only do this for the boats they have berthed or stowed ashore in the UK. Andy is berthed in SCM Spain where it has in my experience proved unnecessary. I did dehumidify on occasion when berthed in the U.K.
 
I can only confirm that in 9 years in SCM it has not proved necessary for me but there are lots of variables not least include air leakage rates, insulation levels even location in the marina. I doubt I would bother. I suppose if I where a broker I may take a view��
 
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