New Heat/AC unit

[S/V Mother Ocean]

Looking for a central Heat/AC unit. Anyone know a place that sells a good name brand cheap ? ? ? any brands better than others ? It must be able tyo be owner installed. Any advice is greatly welcomed.

Dan

[Pblais]

None of them are cheap. The installation matters. The duct work sucks. Consider the allergy free duct work. Mold loves to grow in it. Don't wimp out on the the salt water pump. It's easy to think are all the same and they are not. You want a short salt water run with a big pump and quality sea water strainer. It's not what comes to mind but it's awful when they fail you.

[Icetug]

I agree with Paul. Get a good pump and fittings/hoses. I installed a Mermaid reverse cycle unit myself purchased from Defender. The duct work is the worst part. For owner install get a unit that has the evaporator, compressor and condenser all on one skid.

[Pblais]

For owner install get a unit that has the evaporator, compressor and condenser all on one skid.

I'll agree with all that too. Don't forget the condensate drainage. It has to go someplace. Some units use a pitot tube to suck it out the coolant out flow. That works but they get clogged from assorted dirt and salts in the air. One of those details they don't tell you clearly. A drain to the bilge may be better.

I also found the heat cycle works great until the water gets below 40 degrees. Above that it's amazing that it can heat better than it cools. If you need heat you may also have a navigation problem. One of those latitude things.

[rebel heart]

We use a throw away electric space heater when plugged into the dock, and a bulkhead mounted diesel cabin heater when not. For AC, there are some clever fan placements and lots of airflow.

[bobfnbw]

One mans cheap is another mans....

I have a flagship 16.5 btu unit and will add another 12k soon as I can find the funds for it.
I agree that the salt water pump is important as is the duct work. The PO installed mine wrong and it was wrong. You have to ensure that the correct number of ducts are installed that your unit supports.
If you really want cheap go to home depot now while its still winter, buy a cheap window air unit and put it in your companionway with a extension cord. Danger waiting to happen. Of course the medical bills won't be cheap....
Besides with a cat, you sure you want to load it down with a heavy ac unit ?
Just get a couple of hella fans and put some ice behind them.
But if you want a quality unit, check out the link. They have units for cats as well.

Self Contained Marine Air Conditioning Systems - Prices & Specifications

[Icetug]

The cheapest and easiest way to do the A/C is one of the all in one portable units that sit inside and use hoses to vent the heat through a hatch or port. Of course, the condensate will slop out of the unit when you get underway, and they are pretty large, with rollers on the bottom to allow it to wander around the cabin at odd times. Some of the units even have a reverse cycle or heat strip feature. If you want cheap, have lots of room, and only really need A/C at the dock then that may work for you. Just unpack it, lower it inside, run the hoses outside, plug in, and enjoy. About $500 versus $1500-2500 plus your labor for the marine unit.

[amytom]

I installed a 20K BTU Ocean Breeze unit I bought directly from the manufacturer in Stuart, FL. Owner of the company has been very helpfull during the install and anytime I've had a question afterwards.
For a catamaran I would look at your duct possibilities, two seperate units might be better. Also two smaller units means you can cool half the boat while charging batteries all from the Honda 2k generator.
For the condensate, a gravity drain to overboard discharge is best. If not, are your bilges dry right now? If they are dry then keep them that way run the condensate into a seperate shower sump box and pump overboard.
Another thing to look at is the heat cycle, if you're in cold water a reverse cycle heat won't work very well. You'll want resistive heat elements but they do use more power.

[gonesail]

it's important for the unit to drain well so make sure it is either level or slightly tilted toward the condensate drain. make sure the condensate line is sloping down from the unit. it is nice for the AC to drain into the shower sump. the main supply duct should be fairly close to the unit. use a good raw water pump with a bronze strainer along with marine hose. thru bolt the unit to some kind of strong platform. measure 5 times before you start cutting. i had a tough time finding the teak grills that i needed but finally got them.

[boatpoker]

bobfnbow did not mention that the Flagship unit works on reverse cycle for the cooling side but is straight electric on the heat side. This has a number of advantages. My unit is 18 years old and I have twice had to replace a relay ($16.00).

Flagship customer service is second to none and they will spend all the time you need on the phone to help you get it right.