Marine Air Condtioner - Cost to Install?

[Target9000]

Hi all, this is Target's GF. My questions are usually more on the simple side of things.

Any one have any idea what it should cost to get a 9000 BTU Webasto FCF marine AC unit into a 27' 1974 Ericson Sailboat? We have the unit, pump and duct work and it will be out of the water for all neccessary thru hulls, but i am trying to get a ball park price for the install.

Also does anyone know if this unit and size will be sufficient for cooling the 27' boat in the summer when temps are in the 90's and 100's? water temps in the 80's?

Thanks so much

Target GF.

[GordMay]

A 9,000BTU/H A/C unt would be in the right ballpark, for your E27.

A “rule of thumb” recommendation for sizing marine air-conditioning is about ± 14-to- 15 BTU/h per cubic foot of cabin volume.

More glazing, pilot house, etc = more heat gain; so perhaps up to 17 BTU/h per cu. ft.

A professional will size the air conditioner based on the latent cooling load (which considers the relative humidity of the air), as well as the sensible cooling load (which considers the outdoor & indoor design air temperatures) for your boat & location.
A (theoretically) perfectly-sized air conditioner will run continuously during the hottest 2.5% summer design (outdoor) temperatures.

Don't buy an oversized unit. An over-sized unit short-cycles (turns on & off too rapidly), so doesn’t properly de-humidify*, and uses more energy (starting currents).

On the other hand, make sure any ducting is sized large enough to allow low-velocity air distribution.

* The ability of the air conditioner to remove moisture (latent capacity) is lowest at the beginning of the air conditioner cycle. The moisture removed from the indoor air is dependent upon the indoor coil temperature being below the dew-point temperature of the air. The moisture then wets the indoor coil and, should the unit run long enough, will begin to flow off the coil and be removed out of the condensate drain. For short cycles (< 10 min, or so), the coil does not have time to operate at the low temperature, and when the unit stops, the moisture on the coil evaporates back into the indoor air. Thus, in humid climates, a properly sized air conditioner will do a far better job of removing moisture from the air than oversized units.


HTH,
Gord May

[Nice N Easy]

I too live in SE Louisiana, and my first question is why. I hope this doesn't sound like a smart a%$ answer. Not intended to be. It does get hot here in the summer time. But the AC is not going to be of any use except when you are tied up at the dock. Mostly when sailing, and anchoring out is not too hot. So, unless you live aboard, or spend most of your time at the dock, why bother. All sailboats are limited on storage, so use the space the AC would take up, and sail more.

[Kefaa]

It is about $2k to have someone do it in MD, pre-recession. However, I read this http://www.practical-sailor.com/marine/ac.pdf and http://www.practical-sailor.com/marine/diyac.pdf I am going to try it. I believe I can get better equipment with the savings.

Warnings I have been given:
- you lose space, even on the small units it is at least a storage area + 3" hoses
- be sure condensation has somewhere to go and the bilge may not be your best choice
- ensure you have something to absorb vibration and noise.

[Pblais]

Size seems good to me and of course I would agree with all Gord added. We had a 12,000 BTU on a 33 ft boat but the deck was solid glass and so was poorly insulated and that was almost enough BTU's. Being shorter should come out about right.

Costs for the install are going to be a wide range since the installation includes running duct work in a boat that is finished, wiring an AC circuit that may or may not mate with a good wiring system, then lastly mounting the unit and running the through hull. The destruction required may need to require more money for the repairs. Few parts of this job could considered "usual". Location decisions made poorly will add cost and reduce how easy the job goes and the maintenance down the road.

For the through hull you want the absolute shortest run in and out possible with as few bends as possible. Invest in a quality cooling pump as the cheap ones (like Cal) go bad and are not repairable. A March pump comes with an all Nylon pump head that you can carry a spare for and the motors are quite good. They cost more. You want a good sea strainer for the raw water that you can actually get to without standing on your head. They require cleaning. Pumps and strainers can be ignored for the first few years then you learn why to get a good one up front. Big boat or little boat, it's all the same after you size the unit. The cost of installing a large unit is not much more than the install of a small unit. As Gord notes too big is bad.

Making a nice neat installation done properly takes extra time vs. a quick poorly done job. Of course you want a neat good job done cheap so find someone that has done at least a half dozen before. Plan the entire install so you know what to expect as far as fit and finish work. Done properly you should expect a good 20 years of service.

As rough estimate the cost of the unit was the cheap part. I can't see it being less than double to triple the cost of the unit to complete the job totally. There is a fair bit of materials left that didn't come with the kit. Depends on how nice a finish you want and how easy it is to run wires and duct. Don't cheap out on the materials for the rest of the install! These are the parts that will haunt you if they are not done right.

[Chief Engineer]

Where do you plan on putting it on you boat?

I have an Ericson.....Summertime, I mount an A/C unit in the companionway.....I am still agile (believe it or not) so it is not a big deal to get around

$2,000 for an install?

I gotta get in the A/C bidness

[Target9000]

Originally Posted by Chief Engineer

Where do you plan on putting it on you boat?

I have an Ericson.....Summertime, I mount an A/C unit in the companionway.....I am still agile (believe it or not) so it is not a big deal to get around

$2,000 for an install?

I gotta get in the A/C bidness

This boat will be a liveaboard boat. So mounting anything in the companion way would prevent being able to lock and secure the boat as well as make it more difficult to take out sailing.

We are looking for a place inside the boat (although we dont know where yet cause we havent seen the boat in real life yet-we had a survey with a video but we havent seen the boat)

I've called a couple marinas and most say the install should be like $500 or so. $2000 is too much for an installation-for that cost id try to do myself. Maybe the $2000 includes the unit?

So a bigger question than the cost of the install itself is where to put the A/C in the Ericson 27. Anyone that is familiar with this boat your suggestions are welcome.

If i understand it right the A/C unit has to be above the waterline and the pump has to be below. We would like to run two duct systems-one into the salon and one into the Vbeth.

There are two Setees, a quarter berth, area under the companion way, a hanging locker and a Vberth. Am i right in thinking that the A/C would be better more in the middle of the boat where the duct run wouldnt be too long.

Thanks so much for all your advice

Target GF

[bobfnbw]

About to install our new ac in our E40. Previously I had one 16K btu unit that a PO had installed, did a piss poor job of it and the thing never worked properly.

With the new system, it will work a lot better. Mostly because I am doing it. It will be done right.

Some of the things you need to know.
The further away the exit grill is from the unit the better. You do not want cold air recycling thru it. This will ice the unit up and cause it to trip.

Good water flow is essential. Get a march pump. install it on a thru hull with a good quality strainer. Since you will not be running the engine and the AC at the same time, you "MIGHT" be able to use the main engine thru hull and stainer for this install. My guess is you will only be using it when at the dock, connected to shore power. Just have a way to shut off the flow to the AC when the engine is running.
So then you would only have to install a above the waterline discharge. Not a hard thing to do.
The power for this would come from a separate breaker, sized correctly for the unit.
Do not just use a 15 amp breaker cause that is what you have open. Make sure it is the right size. Breakers are cheap.
Make sure there is a filter for the unit. Dust and dirt will rapidly clog up the unit if you don't.
Ensure that the condensation line is plumbed correctlyl. You do ont want condensation to sit in the drain pan. It should not drain tonto the bilge. Connect it to your shower grey water tank if you have one.
T here is no reason to pay someone to do this. Its not rocket science. Just read the installation book that came with it first. Remember that AC can kill on board. Size the wire for Voltage drop correctly. The pump must be low and get good flow.
A small AC unit doesn't take up that much space.
Remember to run the duct as far away as you can, and do not put the thermistat where the cold air from the duct will hit it .
Hope this helps some.
Bob

[bloodhunter]

Target
If you haven't already done so I would suggest you either make or have made an awning that will cover your boat from the mast back to the stern of the boat. Would guess it would be about 18-feet long and about 10-feet wide with four of those telescoping awning oles to keep it spread out. You could use a light-colored or while plastic tarp you can get in the discount places (like Ollies down here). Keeping the direct sun off your cabin top will go a long way to reducing the load on your AC and also keep you a lot cooler when you're at anchor.
We have an awning the does this for our boat and in the Caribbean and at anchor in the Chesapeake it works like a charm. This summer we bought one of those Cruisair AC units on e-bay. It fits in our forward hatch and keeps our v-berth nice and cool at the dock. Under way the AC stays on land and we rely on multiple fans.

[Target9000]

So I went to sailboat data and made some rough scaled measurement of the boat (assuming they use a scaled drawing) and I think the AC can fit in the area under the companion way above a fiberglass locker that would hold an engine (none there now). The locker under the companion has a removable top and front.

If we left the removable top and put the AC up there im thinking it may fit.

11 19/32"-height
approx 15" X 15"-base

If there isnt enough room Im thinking we could easily build a recessed top board for the locker that would accomodate the unit.

Im attaching a rough drawing of what the arrangement would look like with the waterline shown.

Any opinions of this setup? We are most likely going to have a professional install the unit but with all the horror stories I read about poorly designed systems I'd like to have a good handle on what would work well and what wouldn't so I can present the installer with the ideas to help him if he needs it.

Thanks so much.

[jkleins]

Originally Posted by bobfnbw

Ensure that the condensation line is plumbed correctlyl. You do ont want condensation to sit in the drain pan. It should not drain tonto the bilge. Connect it to your shower grey water tank if you have one.

Bob

Why not put it in the bilge? I have read this before but can't figure out what a little fresh water would hurt down there will all the salt water. If anything wouldn't it dilute the salt?

Jim

[Target9000]

If the condensation is run into the bilge would an automatic bilge pump be best you think?

[bobfnbw]

You should not use your bilge as a grey water tank. True to bilge pump will remove it, but not all of it. If you have a dry boat, then keep it that way. If you do not, then find out how to get it so. On of the things a AC unit does is to remove water from the air, making it cooler. You are asking the unit to work harder when you do not remove the water from the boat. Also, that water can leak into the laminate causing problems, it will support the growth of mold, and it is just a genuinely bad practice to do it that way.
Plumb it to a grey water tank. Does't have to be large. Use a pump get rid of it.
Your boat will thank you.

Bob

[Sailmonkey]

Target,
I used to install for a dealer in Kemah, TX. It's hot here and I know how to make an A/C work. The diagram you've drawn will be problematic at the best, your ducts are way too long.
In your boat (I assume you've not already purchased the unit) I'd go with a split unit. The compressor/condensor mounted under one of the quarter berths and the evap mounted under the port side settee. The water pump would be installed in the engine compartment to muffle the noise and the strainer somewhere convenient.
If you mount the evap unit under the port side settee you can then run a 5" duct into the the hanging locker, and "T" if off to a 3" duct for the V berth. The main cabin air would then exit the top of the hanging locker and vent aft.
For a good professional install you're looking at 2 to 2.5 days of time at the going rate.....whatever that is.
insist on insulated ductwork in the hanging locker otherwise you'll end up with some condensation on your clothes.

http://www.cruisair.com/remotesys.html

[Chief Engineer]

One of My boats in an Ericson 27.

That little watch berth could be an option (all the way in the back).

I am heading to my boat tomorrow and will try to come up with some ideas for you.