With our current boat our concern has been all about staying warm in northern waters but we are now on our way south and wondering about staying cool. We have plenty of hatches and an air scoop but we have been wondering about fitting air conditioning. We have s 4kva 240 volt A/C diesel generator and also have ducts in place for heating and dehumidifying.

I was wondering about simple air conditioning solutions that would be easy to install and not too power hungry.

Does anyone have any recommendations?

Simon

Hi Simon and Sally,
I will share some thoughts on air conditioning in warmer climates, but if you have made up your minds to have a/c, then I am not able to help with the a/c gear choice. Alchemy has spent considerable time in the hot areas of the Mediterranean, Caribbean, Bahamas and in the Central American countries of Honduras, Belize and Mexico and in Florida. We had no a/c.
A few considerations:
In this part of the world, most of the time spent in the really hot areas is winter when the temperatures and humidity are more moderate. One goes N in hurricane season. Live-aboard over-summering, say in the Rio Dulce in Guatemala or in Florida, a/c may be a life-saver.
If you plan frequent long or longish stays in a marina in Florida, then a/c may be nice, even essential. Friends have bought a small relatively inexpensive window style household a/c unit and figure a way to use it in their hatch. Some find a way to store the unit on the boat when they leave while others just leave it behind, especially if bought second hand as is easy to do.
Frequent stops and stays in marinas would make an inboard a/c unit quite nice. (A note, many UK friends are pleasantly surprised by how seldom they needed to go into a marina: anchoring out possibilities are usually ready-at-hand and one can (and does) go months without a marina.)
Marinas are a cooling challenge as they are considerably warmer than anchoring out, usually have less of a breeze and the breeze is not over the bow, and, most importantly, swimming is not readily available.
We anchored out almost exclusively and went into marinas primarily when we were doing some land cruising and needed a place to leave the boat. Most days at anchor, especially hot days we would be in the water multiple times which always served to bring our internal temperature down and we like to swim. The boat is a 40-foot boat and we have 7 fans, so there is always the possibility of having moving air on you. We could always have shade in the cockpit with moveable screen. We also we able to get to areas of the boat where adding insulation made sense: the headliner for example (details if interested).
T anchor, friends with a/c sometimes use it for an hour or so before bedtime to take the edge off internal boat heat and facilitate getting to sleep
Aesthetically, a/c cuts you off from the world: you must be closed up, the last thing I want on a boat. I like to hear what is going on around me. At anchor, your genset must be going.
Our experience: I do not think we ever were uncomfortable enough to consider a/c. My personal criterion for becoming grumpy about heat is when I can’t sleep and most nights at anchor, we were just fine and if too warm, we turned on a fan and then usually, pulled up a sheet. When really hot (Italy), we did what the locals did, activity mornings and late, with a good siesta. Worked a peach (and becomes a bit addictive).
Please, come back with questions/comments.
My best, Dick Stevenson, s/v Alchemy

Thanks Dick very useful comments born of experience.

We are certainly not wedded to the idea of A/C and all the noise that goes with it whether powered by generator or shore power. Our experience thus far of warm water sailing was in our old boat which had no fridge, no freezer, no fans and no cockpit shade. We are anxious to avoid the mistakes of the past! Our current boat is very well prepared for the cold but we have not yet even equipped it with fans and so we are really just considering options as we drift south.

I take your point about cruising in the cool months and that is indeed our plan as I am also keen to retain the day job and return to work leaving the boat to roast. The fact though that we will have to lay the boat up from time to time probably means that we will be forced to do more marina time than if we were permanent live aboard and it is those stifling marina nights that we remember from summer charters in Turkey that have tainted our memories.

My guess is that if we do go down the A/c route it would be used nearly always on shorepower during enforced marina stops at the beginning and end of a sojourn on the boat. But, as we have a generator, it might occasionally get used at anchor in exceptional circumstances. Installing a/c on our boat probably wouldn’t be too great a task as we have air ducts everywhere (for heating) and can easily tap into a through hull for the heat exchanger. We also have 240 volts via shore power and generator. The units I found on the West Marine website are relatively inexpensive in yachting terms so it’s not out of the question.

What is evident on our way south is that we need to fit fly screens and fans as an absolute minimum as we neglected those in the original specification. All advice on keeping cool most welcome.

Simon

Hi Simon,
Much of what you might have done for cold weather cruising will help with warm weather: insulation goes both ways for ex.
Off the top of my head as we have not had to worry about being too warm in many a year.
1. We had a foredeck “tent” to keep sun off the cabin top. Many boats have an awning: often full deck and keeping the sun off of you and the deck makes a huge difference.
2. We have a lot of Hella fans and they have lasted well. Install with a fuse as motor can lock and heat up/start to burn. Caframo fans move more air, but were not as reliable. (all fans installed 15+ yrs ago and most are still going strong. Fans may have improved/changed).
3. Warmer water (20-25C) usually takes a big toll on the duty cycle of your frig/freezer. We added insulation on the outside to the extent reasonable and also added insulation on the inside of the freezer, especially on the bottom where there was closer contact with the hull and the warm water.
4. We noticed, when really humid, moisture on the top of our frig/freezer on the counter top. We started using a ~~2cm “condensation pad” covering the tops of the frig/freezer: easily removed when there was action in the galley, but helping for those long periods of inaction. Where there is condensation, there is a leak of frig/freezer cold.
5. As mentioned before: we had gaps between the headliner and the hull which we filled with insulation. This made a huge difference on sunny days, especially when the aforementioned tent was not deployed.
6. We had a bimini and used a large lightweight movable “scrim” with big clips to give shade where we wanted it.
7. Our dodger windows had light reducing “shade” screens that could be installed on the inside of the windows. Our dodger’s center panel could be removed for good air flow.
As I think of other items, I will add.
My best, Dick Stevenson, s/v Alchemy

Hi Simon,
Re your Air Con question, I think Dick in his usual thoroughness, has covered much of what I would have written.
A couple of points though. We also use Hella Fans, and they are superb for shifting air about, and are really durable. After 11 years we have replaced a couple, but since 9 of those years were spent in the tropics not bad. We managed to get a couple of Oscillating ones as replacements which were on an offer by Hella at the same price as fixed ones so maybe if fans are on your shopping list bear that in mind.
We also obtained a couple of spare mounts, so we could have the facility to move the fans to a different position. We did not need one in the fore cabin, only when we had guests, and also on the passage berths, it was great to be able to have a fan on ones bunk during off watch times. So flexibility of the position is in my opinion a useful feature.
The other thing we found which I believe is a US product is called a Port Visor by Seaworthy Products.com These visors are superb and enable you to leave cabin windows open without any rain coming in the window. On really heavy tropical downpours as our windows are fairly close to the deck, we did get occasional bounce back of the rain hitting the decks by the window, but as long as you were on board no problem.
In Trinidad we rented an air con unit and put it over the saloon forward hatch and rigged up some 100mm ducting to spread the cool air around the boat. It worked well. In Venezuela we bought a unit, and again mounted it as in Trinidad. However well it worked, we started to question why we were sitting down below on a really hot day. This is when we came to the conclusion that it was time to land travel to other countries during the Hurricane / Cyclone Season. We did not want to be on the boat during those times.
We have lots of Canvas to protect us from the sun, and have over the years fine tuned our use of it so we can be shaded and comfortable not only at anchor but also whilst under sail.
Hope this helps. Maybe you can plan your return to work times during the wet humid season!
Cheers
Brian S/V Darramy

Hi Brian & Simon,
Brian nice addition reminds me: the fan in the off-watch sleeping area also serves as a white-noise machine facilitating sleep by providing a "whirr" on top of noise sailing and people make. Also, although we do not generally use them for cooling persons, but when buying fans, I would suggest a portable one with a big clip and a "cigarette lighter" type 12v receptacle and a long cord. Ours has been surprisingly useful off and on.
My best, Dick

Brian,
Another really helpful post as I hadn’t a clue about what fans to go for and hadn’t thought of additional mounts in berths that are used less frequently.
Port Visor by Seaworthy Products.com seems like a great idea too. We are already in the process of fitting fly screens to all of our hatches which we haven’t needed to date.
I had not really thought about hatch mounted Air Conditioning which is obviously an easy fit for marina and harbour use and it is interesting that you found it effective.
It is certainly our intention to return to work during the various hot and sticky seasons.
Many thanks.
Simon

I know they are expensive and mains powered but has anybody got any experience of the newer generation bladeless, so called, silent fans? it looks like they might be quite good at night on shorepower as they rated at 56 watt as opposed to Hella's 6 watt. If they really are 75% quieter then that may be a bonus. In the UK Dyson seem to be pushing them.
Simon

Hi again Simon,
I just realised that all stuff over ther is 110 volt, not sure what Shimshal is set up for, but the air con units we used we wired directly into the pontoon shore power plug so a separate lea.
Cheers
Brian

Brian,

We have an built in isolating transformer which is currently setup to step up our shore power feed from 110 volts to 240 volts. I have noticed that some 240 volt A/C units can run on both 50Hz and 60Hz.

Hiring a local 110 volt unit wouldn't be ideal for us as we would have to run it on yet another transformer from the generator or on a direct feed from shore power. Sooner or later i would get in a muddle and blow something up!

I think if we do go for A/C it would be an installed 240 volt unit that would run on both 50 and 60Hz. That we would give maximum flexibility.

Still not convinced we need air conditioning and this thread informing the decision.

Simon