Manatee Air-Conditioning

HiDHo · Aug 8, 2014

Need some "been there done that" type information from other Manatee owners as to what works regarding air-conditioning our Manatee.
We use two 30 amp shore power cords when at the dock and a Northern Lights 5 KW generator when underway or at anchor on our 1987 KK3669. Presently running a worn out Cruisair 16,000 BTU R-22 split system heat pump that needs help with the heat load. I have used guides to caculate the Manatee needs about 36,000 BTU's of cooling. Is that what other Manatee's require ???
I'm looking at the new air-conditioning units from Cruisair running R-410A refrigerant and advertising 20% increased efficiency. Also there "Smart Start" single phase soft starter package seems like a perfect solution to the high starting amps required for air-conditioning compressors.
I'm open to information on how your Manatee is setup since marine air-conditioning, placement of units, etc. is always a challenge.
Any information and or photos would be a help making the right decision for our Manatee.
Bill

healhustler · Aug 8, 2014

Hey Bill. I'll be interested to follow this thread, as I'm faced with precisely the same issue…..old 16K BTU CruiseAir I just recon'd and looking for a second unit for the pilothouse and/or help for the cabin. These FL days are too much for a single 16K unit.

HeyJude · Aug 8, 2014

HEY JUDE has 16k AC & is insufficient during the summer. We have a covered slip & can maintain 80* in the shade. I've seen the compressor unit mounted under the helm, under sink, in the round storage bin & in the berth closet. The highest time KK36 has an RV style unit on the pilot house roof.

Mossesq · Aug 11, 2014

My Cheer Men 42' does not have AC and I need to put it in. Two AC guys have looked at it and neither can figure out how to duct it (walls too thin, not enough cabinet space to run ducts up high). Has anybody with a similar issue (not necessarily with similar boat) run into a problem where to run ducts? If so what did you do? Apparently this applies to a split or a self contained system. Thanks.

Hot in the Cal Delta.

healhustler · Aug 11, 2014

HeyJude said:
HEY JUDE has 16k AC & is insufficient during the summer. We have a covered slip & can maintain 80* in the shade. I've seen the compressor unit mounted under the helm, under sink, in the round storage bin & in the berth closet. The highest time KK36 has an RV style unit on the pilot house roof.

Phil: You unit must be even more clapped out than mine. My old 16K CruiseAir will keep the boat cabin below 80, even when the sun is bearing down in 95 degree heat...no shade. But I want more, and another 12 - 16 K unit under the helm will probably be the answer. I've been experimenting with two different 9K BTU domestic floor units, and one unit will keep the boat live-able and fairly dry, but not on days over 85. I'm still going to try it in the pilothouse to see if it's enough up there, but I doubt it unless I pay the bucks for that 3M 99% UV barrier film (expensive). To tear the guts out of one of those floor units and adapt it to under-helm installation would be pretty simple and cheap. It may be worth while to invest in the 3m stuff instead of another bigger A/C.

HiDHo · Aug 11, 2014

Larry one of the local marine A/C mechanics told me placing a packaged unit under the pilothouse console won't work. I thought this would be a great spot but he pointed out that the sea water circulation pump would not be able to pump water that high to the condenser. That spot works for a split system with the compressor/condenser down below the water line and the air handler/ evaporator coil fed by copper tubing suction and discharge lines under the console in the pilothouse. The condensation can be gravity drained to the bilge.
Mossesq, try fitting packaged units into settee storage, or other similar areas where the unit discharges cool air directly into the space to be cool, no duct work, it will however need a return air some where ajacent to the unit. The new packaged units are very quiet and a compressor sound box can be added to make them even more so.
The best system I've researched is a chilled water system that has all the mechanics down below and piped chilled water to individual chillers sized for the compartment they serve. Very nice but very pricey.
Bill

healhustler · Aug 12, 2014

Mossesq: I think your post would draw better interest if it were re-published as a new thread under "Other Trawler Systems". That way, members with similar boats and A/C issues can share in the information instead of it hiding here in the Krogen section.

As far as ducting, I found that working with the aluminum faced duct board available at Home Depot and Lowes, etc. and some aluminum tape, one can make nearly any size or shape of insulated duct that can fit in corners, against existing walls or whatever, and can be covered with wood veneer very nicely. It's fun to work with.

Bill: I'm still on the fence about what type of A/C unit to use in the pilothouse. I hate the idea of cutting my roof and adding 135 lbs. up there, but a main engine driven compressor would be nice, considering that practically all the time I'd want the pilothouse AC would be underway.

CPseudonym · Aug 12, 2014

healhustler said:
Mossesq: I think your post would draw better interest if it were re-published as a new thread under "Other Trawler Systems". That way, members with similar boats and A/C issues can share in the information instead of it hiding here in the Krogen section.

Or I could just move it

Thanks for the heads up

Shoalwaters · Aug 13, 2014

Not a Manatee owner but hopefully my experience with my 1984 DeFever may help. Two of the original self-contained (ie not split-unit) air conditioners were still in place when I bought the boat in 2008. I went through the whole process of rehabilitating the old a/c's and installing new ones. This is the original post, but here are the bones:

There may be nothing wrong with the refrigeration side of an old a/c that struggles to cool the cabin - the problem could be elsewhere and fixable.

Make sure there is a good flow of water coming out of the overboard discharge from each a/c unit. Flush the pipes on each unit with something like Ryd-Lyme to ensure that the inside of the coils doesn't have a layer of crud hindering heat transfer. Fitting a dedicated Perko strainer close to the seacock and before the pump is strongly recommended.

Many (most?) self contained a/c's have squirrel-cage fans. The fan blades are narrow strips of metal bent into a shallow "V" about their long axis. Over the years, the "V" fills up with crud so that, at first glance, the blades appear flat. The fan rotates but it doesn't move much air - same as a dirty propeller. Cleaning and repainting the blades can produce a remarkable increase in the fan's performance.

There is not much point in making the fans work efficiently if all the power is wasted pushing the cool air through rough ducting and around lots of "square" corners. This describes the original setup on my boat to a tee. Locate the air outlet as close to the a/c unit as possible. 4" PVC waste pipe makes a nice smooth (cheap) duct. Insulation is essential. Two layers of the thin bubble-wrap with a foil skin on each side work well.

Make sure that the return air path (where the a/c sucks the hot cabin air back in) is unobstructed. Two of my units were located so close to cabinet sides that there was hardly any space for the air to get in. Aluminium louvers were the inexpensive solution to my problem. There should be a bug-screen immediately before the return air radiator. Make sure it is clean.

Those who have problems running ducts due to lack of cabinet space might consider the advantages of PVC pipe. It doesn't take up much room and is self supporting over fairly long runs. Making a varnished wooden trunking to hide it is not difficult.

healhustler · Aug 13, 2014

Great info, Mike. Your comment of streamlining the flow through the ducting also has me thinking about that accordion style piping I have here and there. One 2 ft. section isn't even insulated. Your setup has me re-thinking. I hope Mossesq is seeing this.

siestakey · Aug 13, 2014

I am not sure about the other things but I am slowly upgrading systems as they break replacing 2 of my 4 AC units have now been replace with split cruiseair and the soft start makes a huge start up load difference

I have also found that here in southern waters in the summer the recommended seawater pump size needs to be increased this actually lowered the overall draw

ben2go · Aug 13, 2014

Shoalwaters said:
Not a Manatee owner but hopefully my experience with my 1984 DeFever may help. Two of the original self-contained (ie not split-unit) air conditioners were still in place when I bought the boat in 2008. I went through the whole process of rehabilitating the old a/c's and installing new ones. This is the original post, but here are the bones:

There may be nothing wrong with the refrigeration side of an old a/c that struggles to cool the cabin - the problem could be elsewhere and fixable.

Make sure there is a good flow of water coming out of the overboard discharge from each a/c unit. Flush the pipes on each unit with something like Ryd-Lyme to ensure that the inside of the coils doesn't have a layer of crud hindering heat transfer. Fitting a dedicated Perko strainer close to the seacock and before the pump is strongly recommended.

Many (most?) self contained a/c's have squirrel-cage fans. The fan blades are narrow strips of metal bent into a shallow "V" about their long axis. Over the years, the "V" fills up with crud so that, at first glance, the blades appear flat. The fan rotates but it doesn't move much air - same as a dirty propeller. Cleaning and repainting the blades can produce a remarkable increase in the fan's performance.

There is not much point in making the fans work efficiently if all the power is wasted pushing the cool air through rough ducting and around lots of "square" corners. This describes the original setup on my boat to a tee. Locate the air outlet as close to the a/c unit as possible. 4" PVC waste pipe makes a nice smooth (cheap) duct. Insulation is essential. Two layers of the thin bubble-wrap with a foil skin on each side work well.

Make sure that the return air path (where the a/c sucks the hot cabin air back in) is unobstructed. Two of my units were located so close to cabinet sides that there was hardly any space for the air to get in. Aluminium louvers were the inexpensive solution to my problem. There should be a bug-screen immediately before the return air radiator. Make sure it is clean.

Those who have problems running ducts due to lack of cabinet space might consider the advantages of PVC pipe. It doesn't take up much room and is self supporting over fairly long runs. Making a varnished wooden trunking to hide it is not difficult.

That's good info right there.Sometimes it helps to go back and check through the basics.

FF · Aug 14, 2014

I would go modern , Mitsubishi Electric US, Inc. Cooling & Heating | HVAC and install 2 of the largest mini split units they sell that will operate on 120V .

220V is not found a every marina, therefore the 120v suggestion.

No seawater holes , no pumps and if heat is required the Mini Split units will work to about 30below!

I saw dozens mounted all over in Europe ,this June and July on many different sized vessels.

healhustler · Aug 14, 2014

For what it's worth, this is the original Krogen Manatee that captured our hearts in Hong Kong. Look close and you can see a domestic wall mounted unit (photo 2) in the salon, and the other half of the split unit was in a box built behind the pilothouse (photo 1). The other box on the left of side was storage. I don't know how well it worked, but the boat had lived most of it's life as an business office at the dock.

HiDHo · Aug 22, 2014

We chose to go with the addition of a Cruisair packaged unit model STX16 with the Smart Start option. This 16,000 btu heat and cool unit fit very nicely into the pantry storage locker on the forward starboard side of the companionway that leads to the stateroom. The installer was Diesel Don who is a certified Cruiaire/Marineaire installer, his 40 years of experience sold us. The install took about 13 hours but that will vary for each Manatee. First test of the additional cooling was yesterday with the outside temps at 92 degree's and heavy humidity and the inside was a nice 74 degree's granted we still where at the covered dock at our marina. Don also balanced the amp loads on the two 30 amp supplies to our power panel and calculated that the 5 KW NL generator we have would be running very nicely with a heavier electrical of the two units. He is also certified Nothern Lights installer and mentioned that lightly loaded generator are not a good thing, causing the cylinder walls to glaze, so our generator should be operating with a much better work load which is a good thing for a diesel engine. I will follow up with photos and underway/anchored tests soon.
Bill

Wally · Aug 23, 2014

Just for info...Summertime has a unit under the steering console dedicated to the stateroom and it appears to work fine. We have not had to use it in high heat and humidity however.

CPseudonym · Aug 23, 2014

FF said:
I would go modern , Mitsubishi Electric US, Inc. Cooling & Heating | HVAC and install 2 of the largest mini split units they sell that will operate on 120V .

220V is not found a every marina, therefore the 120v suggestion.

No seawater holes , no pumps and if heat is required the Mini Split units will work to about 30below!

I saw dozens mounted all over in Europe ,this June and July on many different sized vessels.

Good advice. Have no experience with them in a marine environment but have used them for years in land based installations. Bullet proof little units that can be fit into ridiculously tight spaces making them ideal for retrofit applications. As healhustler's photo demonstrates there are always athletically pleasing ways to camouflage the units due to their small footprints.

HiDHo · Aug 24, 2014

Here are the photos of the new Cruisaire a/c heat packaged unit installed. The blower discharges into 7" insulated flex duct. Nice feature is the blower has a variable speed setting to quickly bring the temperature to the thermostat setting at a high setting, then tapers back to a slower (less noise) speed. The existing 1" seacock was large enough to supply circulation water to both the new and older unit using a 1000 GPH pump. The specs on this pump would feed a packaged unit under the pilothouse console and that maybe our choice when the older split a/c heat unit gives out. The previous post about this not being possible proved not to be the case. The mechanic that provided that information was probable using the specs off a smaller pump. We now have 32,000 btu's of cooling which should handle all but the most extreme hot weather.
Bill

healhustler · Aug 24, 2014

Bill: Looks good. Geeze, that unit takes up a lot less real estate than my old 16K Cruisair does. Bill, get rid of that darned 7" hose and build yourself a rectangular duct out of that aluminum covered foam board at Lowes or Home Depot. One roll of aluminum tape does it.....fun to work with and hugs the closet wall so hardly no interference with the back shelving. I just built my own, will include pics later.

CoolBeans · Aug 24, 2014

Nice installation! Looks like it fits into the pantry closet very nicely!
Dotty

ben2go · Aug 24, 2014

healhustler said:
Bill: Looks good. Geeze, that unit takes up a lot less real estate than my old 16K Cruisair does. Bill, get rid of that darned 7" hose and build yourself a rectangular duct out of that aluminum covered foam board at Lowes or Home Depot. One roll of aluminum tape does it.....fun to work with and hugs the closet wall so hardly no interference with the back shelving. I just built my own, will include pics later.

healhustler · Aug 24, 2014

ben2go said:

Yeah, I know....sorry Ben. I won't be on the boat till Wednesday. I also had the 7" stack in my closet till I built the foam board duct. Wow, what a difference in access to the shelves. I don't know why I didn't think about it before.

ben2go · Aug 24, 2014

healhustler said:
Yeah, I know....sorry Ben. I won't be on the boat till Wednesday. I also had the 7" stack in my closet till I built the foam board duct. Wow, what a difference in access to the shelves. I don't know why I didn't think about it before.

:lol: I'm just giving ya a hard time.

Did you do foam board around the stack?I thought the heat would be to much.

healhustler · Aug 24, 2014

ben2go said:
:lol: I'm just giving ya a hard time.

Did you do foam board around the stack?I thought the heat would be to much.

The foam board was aluminum coated, so no issue with the reverse heat. Home Depot had the round stack to rectangle adaptor, so I just made the duct to fit the adaptor. It was so easy (and fun), that I'm going to do the rest of the ducting with the same stuff. Stick-on insulation tape (also Home Depot) does a great job for insulating the adaptor. I also saved the thick insulation from the old round hose and have reused some of it. My whole system used the round accordion style hose with thick insulation right up to the registers. The flow was impeded by the turbulence inside of the hose, especially in bends. My A/C is old. It needs all the help it can get. Additionally, the unit was resonating the closet floor like a guitar. I cut two of those interlocking floor pads from Harbor Freight and rested the unit on top....now, no resonance. It's old, yeah, but maybe I can get a couple more years out of it. Unlike Bill's unit, the PO ran the duct ran right up the middle of the closet, making the space behind difficult to utilize.

ben2go · Aug 24, 2014

healhustler said:
The foam board was aluminum coated, so no issue with the reverse heat. Home Depot had the round stack to rectangle adaptor, so I just made the duct to fit the adaptor. It was so easy (and fun), that I'm going to do the rest of the ducting with the same stuff. Stick-on insulation tape (also Home Depot) does a great job for insulating the adaptor. I also saved the thick insulation from the old round hose and have reused some of it. My whole system used the round accordion style hose with thick insulation right up to the registers. The flow was impeded by the turbulence inside of the hose, especially in bends. My A/C is old. It needs all the help it can get. Additionally, the unit was resonating the closet floor like a guitar. I cut two of those interlocking floor pads from Harbor Freight and rested the unit on top....now, no resonance. It's old, yeah, but maybe I can get a couple more years out of it. Unlike Bill's unit, the PO ran the duct ran right up the middle of the closet, making the space behind difficult to utilize.

Thanks for the info on that.It gives me ideas for the aft locker.

HiDHo · Aug 25, 2014

Thanks for the information on the duct board Larry.
If I can locate one I'm thinking of replacing the metal outlet vent with a teak trimmed one with horizontal and vertical air direction blades. I think it would direct the air distribution better and with less turbulence. I discovered that a previous a/c installation used the stateroom hanging locker and a 12" x 12" return air vent was installed on the forward bulkhead at deck level. This vent lets us have the option of closing the stateroom door and still have return air to the unit thru the galley and hanging locker louvered doors.
The new Cruisaire 16K only weights about 65 lbs. and has built in vibration damping mounts to the deck. The condenser water overboard hose and thru hull in the photo was drilled at interior deck level and the coring is about 1/2" thick in that area of the hull for reference.
Bill

silentfaith · Sep 3, 2014

Gettin ready for new a/c this week

Velvet has a 16,000 a/c unit that is old. There is a company here in Stuart called Ocean Breeze a/c that make all kinds and I am going to get thier 18.500 unit which is just a tad bigger than my old unit which fits under the galley sink area. I pulled the unit and will bring it to them and they will match the fan exit so all I need to do is plug in the new one I hope. If not will have to get an electrician in. That should cool Velvet nicely.

CoolBeans · Sep 3, 2014

Cool Beans has the original 1600 btu AC. We just installed a thermostat as this old AC didn't have one. It was either off or freeze your butt off cold.

healhustler · Oct 21, 2014

Bill and Ben: Here's the photo of the rectangular ducting in my closet I promised you weeks ago. This shot is with the closet door removed. As you can see, it hugs the wall nicely, only takes maybe 2.25" or so. This photo was after finishing the cutting and tape of the duct board for the main vertical duct. The black accordion duct you see at the top left of the closet is now also the same stuff. Very easy and fun to work with. Getting to the shelves is much easier now.

ben2go · Oct 21, 2014

healhustler said:
Bill and Ben: Here's the photo of the rectangular ducting in my closet I promised you weeks ago. This shot is with the closet door removed. As you can see, it hugs the wall nicely, only takes maybe 2.25" or so. This photo was after finishing the cutting and tape of the duct board for the main vertical duct. The black accordion duct you see at the top left of the closet is now also the same stuff. Very easy and fun to work with. Getting to the shelves is much easier now.

Thanks.That really explains things.I'm looking to make my own ducts like this for a mobile home I have,instead of using insulated accordion type plastic ducts.I'll also consider using this in my boat as well.

Manatee Air-Conditioning

Guru

Guru

Senior Member

Member

Guru

Guru

Guru

Moderator Emeritus

Guru

Attachments

Guru

Guru

Guru

Guru

Guru

Attachments

Guru

Veteran Member

Moderator Emeritus

Guru

Attachments

Guru

Veteran Member

Guru

Guru

Guru

Guru

Guru

Guru

Senior Member

Veteran Member

Guru

Attachments

Guru

Similar threads