Air conditioning install

kloudie1 · Nov 5, 2015

One of the best things if you plan on spending family time during warm/hot weather. .I installed mine 20 years ago. I don't have a P-34 but on my H-34, I installed a 12000 BTU Marine Air, heat/cooler unit. It is marginally small for the really hot days, but is fine for evening night. The heat is fine.. Your boat will need a 12-16,000 BTU unit I put mine under a settee where I could run the air ducting the easiest. In older boats, the ducting is the toughest to run; the power and water is easier, so the decision is: what storage you are willing to give up where the ducting is easiest to run.. You won't regret installing one (correctly)

Jackdaw · Nov 5, 2015

SailingGestalt said:
Hi Folks,

I have a 1985 P34 with only passive ventilation. I ALSO have a wife and two young sons - wife says if I'm going to do any cruising during the hot months that I need an AC. I don't want the cabin top or the home depot free standing, I'd like an integrated system with heat and AC. No genset so I'll be dockside when using. Just wondering what BTU other P34 owners have used and where you mounted the unit. Thanks in advance and happy fall sailing on the lower Chesapeake Bay!

We have AC and love it. But based on your above comment, look very hard at what 'cruising' means to you and how AC will help. As you know it only works when at a dock with 120AC. For muggy nights anchored in some cove or on a ball somewhere, its no help at all.

We find AC almost useless for our style of cruising. Daysailing out of the marina, however, it's a champ.

Ken13559 · Nov 5, 2015

I installed my aircon under a seated space. When anchoring I used a 4-stroke portable genset. If there's other boats around I would dinghy over to check my gen noise level. If it bothers them I re-anchor further away. So far I've no need for re-anchoring.

Gunni · Nov 6, 2015

Your decision will be informed by where you can shoe-horn in a unit, duct the air, and route the condensate water. And while I can cool a 41' boat on the Chesapeake with a 12,000 BTU reverse cycle (and have a second 8,000 that I rarely use), I would think you could get the job done with an 8,000 BTU unit. This will be enough to do the job if you also have your ports shaded, and have fans to move the air around. The combination of cool and dehumidification, thermal reflection and air movement add up to a solution. Use techniques like giving the reverse cycle plenty of time to get the cabin temps stabilized. I typically arrive at our boat the evening before a sail and get the boat cooled/heated and ready for the crew to arrive. I don't want them experiencing temperature shocks, so the boat mostly feels warm in the summer, and cool in the winter, comfortable, but not too comfortable.

BigEasy · Nov 7, 2015

I would recommend a self contained reverse cycle air conditioner / heater. Don't make the mistake of installing one duct for the salon only; the forward cabin & aft cabin will never cool. You really need to duct all 3 spaces which can be impossible in some boats. My boat was not ducted for air from the factory. The original owner's installer decided to install a split system to alleviate the duct runs. The system consists of a 16,000 btu condenser/compressor, a 12000 btu air handler/evaporator that supplies the forward berth and main salon and a 4000btu air handler/evaporator that supplies the aft berth. It is a cruisair system.that is connected by way of a copper tubing supply line and return line. The system works well; however, for simplicitiy and reduced maintenance, I would prefer a self contained sytem with appropriate ducts to each of the main areas. For your boat, I would not consider anything under 12000 btu; preferably 16000btu if you can fit it.

kloudie1 · Nov 8, 2015

Space next to water heater. Self contained unit in space, Ductwork goes into sink cabinet, into side storage and into main cabin and vee birth area... I know your boat is different, just offering as an example.. As Big Easy says, plan ductwork carefully..

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BigEasy · Nov 8, 2015

As mentioned, I have a cruisair split (emerald series) system that the previous owner had installed professionally. I am generally pleased with the installation and effectiveness; however, I think that is unnecessarily complicated for a 35 foot boat. I hate to think about the repair costs if something breaks. My preference would have been a self contained unit. I have looked at the Flagship Marine air conditioner systems. They advertise that they can manufacture a self contained system to fit your space requirements (within reason). They also emphasize that the electrical components (relays, capacitors, etc) are off the shelf items that can be easily purchased with no printed circuit boards in the control panel. Very simple system, easier to repair, and less expensive.
If I had to install another system, I would give Flagship's equipment some serious consideration. Note that I have no affiliation with Flagship what so ever.

woodster · Nov 8, 2015

Ocean breeze has the same type of systems as you described i have one on my boat and am happy with it may also want to look at them ......

kloudie1 · Nov 8, 2015

Other picture didn't make it.

Gunni · Mar 5, 2016

My return is about 4 feet from my saloon vent location. Place the unit thermostat/control in central location that will make sure you cycle properly. My largest vent is the saloon and the vent in my cabin has a damper for control while sleeping.

seadaddler · Mar 5, 2016

Just some help or ideas and would not install less than 12,0000 btu.
Pick a side port or starboard and try putting the ac unit in main cabin maybe under saloon seat
and run ducts forward to vee berth and to rear in mycase is my rear bedroom where we sleep.
I would draw up a sketch or ruff drawing and measure measure and plan it out on paper first.
Maybe even try look at You tube for ideas and helpful hints.
Nick

kloudie1 · Mar 5, 2016

I think Gunni is right on.. The digital thermostat needs to be in the main cabin away from the closely spaced ducts in the vee birth.. as in the Webasto literature: http://www.webasto.com/us/markets-products/marine/cooling-solutions/fcf/

BigEasy · Mar 6, 2016

Shaw,
I have a remote digital controller mounted in the main salon. You are correct that there is a temperature sensor/thermocouple that is mounted near the return air grill. The sensor feeds back to the controller via a connecting wire. On my remote control, there are options to have the fan run continuously or to have it cycle on and off. It is just a personal preference as to which setting to use. The noise doesn't bother me at night while sleeping; however, I don't like the air continually blowing in the bunk.

31seahorse · Mar 6, 2016

SailingGestalt,
Our Webasto is noisy. I might try some matting under the compressor this summer to dampen noise and vibration. The squirrel cage fan blows plenty of air, and in our installation perhaps too much which contributes to the noise in the cabin. The only place we could fit the unit is under the galley sink cabinet (1986 Caliber 28: MARA) with the air intake facing aft toward the standing space of the galley then one air duct facing inboard and one facing forward in the cabin. A small fan helps push air to the V-berth. The thermostat is on the opposite side of the boat on the forward bulkhead of the cabin. If you can avoid putting the compressor under the V-berth that would help if someone will be sleeping there. The water pump, however, is very quiet. Also, be sure to have the water line going up from the water intake to the compressor with no sags or dips in the hose and put the discharge line heading up too. Avoid creating a waterfall outside the hull from the water discharge. Some dock mates may find the noise disturbing. Follow the instructions carefully.