BTU requirements for a 2897 Mariner

C

ChefJunk

Member
exMember
Joined
Oct 30, 2007
RO Number
28882
Messages
454
Anyone with a Mariner/Voyager in the 28' range know what their AC's BTU is?

I am looking at a couple of units. Can't figure out how much BTU's I need.

Also, how is your Vberth's AC controlled? Is there a thermostat in there as well or do you just adjust the vent?

I assume the units sit under the dinette, where is the ducting run to get to the Vberth?

Here is a 16k unit I was looking at but I only have 30 amps to work with and it draws (soft start) 12-14 amps. The 12k unit draws 10-12 amps but I don't know if 12k is enough for a non insulated boat.

I am on the great lakes.

Thanks,

Jim
 
I'm thinking you're better off with the 16K BTU Jim. There's alot of window on that boat!
 
16k sounds high for a 28 footer. At night time, your compressor won't have to run much, meaning your humidity might start to get too high for comfort.

I used to have a 30' Catalina sailboat which has a LOT of cabin space. I cooled it with a 5000 btu CruiseAir deck hatch model. Granted, it didn't do much in the heat of the day, but it kept the boat very comfortable at night. If I had ever installed a permanant A/C unit, It would not have been over 10k.
 
I have the 30 foot santego and the 16k that came with it is just about right. The boat is also insulated as well.
 
I have 10,000 BTU in my 27 Montego...I would not compare the cabin size of a 30' sailboat to a 28 Mariner...they are Huge inside, plus the cabin is surrounded by 2.5 foot high window 360 degrees. 16,000 is the size to go with.
 
Exactly Kenny, those windows are murder in the summertime, although the "7" series windows seem to have at least a tint to them, rather than my clear glass windows. We tried one of those Carry on models on my old 2895, and it did absolutely nothing. I am not sure if I have 12 or 16K BTU in my boat, but I can verify over the weekend and get back to you...
 
quote:
Originally posted by RamSport47

I have 10,000 BTU in my 27 Montego...I would not compare the cabin size of a 30' sailboat to a 28 Mariner...they are Huge inside, plus the cabin is surrounded by 2.5 foot high window 360 degrees. 16,000 is the size to go with.

Click to expand...


Obviously, you've never been inside a 30' Catalina. There's a whole lot of cabin space. True, not much window space.
I have a friend with a 28' Carver Mariner and his cabin space is more cramped than my old sailboat used to be.
 
Yeah, but the radiation of that heat is different. I've been in a Catalina 34. That boat's cabin sole and lower spaces are mostly UNDER the waterline, and as we all agree, has few windows to let sunlight in. The Carver, on the other hand, is mostly above the waterline and has those big windows. It makes a TREMENDOUS difference. Trust me on that...
 
I purchased a 16,700 BTU unit and hope it will be sufficient. I was thinking of going 20 but I think 16,700 should suffice most days.

I am attempting to install myself. I saw an application where they installed it under the v berth then vented it from there. Looked to be a good aftermarket location due to ductwork.

I really want the return air to come from the main cabin though. I was thinking I could put it up there in the v berth, throw the return in the galley.

I am going to pull the fridge out and investigate to see what room lies behind there. If there is room, I am golden and can place a duct in the v berth, galley, and facing aft from the locker that separated galley and seatee. I could place the return in the fixed drawer under the seatee as well.

I will let you know as things progress. I should have the parts in a week and a half to two weeks.

Jim
 
For any 28' mariner owners out there wanting to install HVAC, there is plenty of room behind the galley countertop backsplash to run a duct to the hanging closet located mid cabin.

You will need to remove a little plywood from the v berth closet and from the closet located mid cabin (remove the countertop to gain access). Things were very tight so I carefully drilled 1/2" holes to outline my approximate cutouts (with a angle drill due to 8" clearance in the closet located mid cabin). I then used a high powered rotary tool with a very large ball bearing tipped laminate trimming router bit to clean up the work. I have one duct on the aft end of the closet mid cabin, one from the v berth closet on the partition in the galley facing aft, and one facing forward into the v berth.

Overall, I lost all of the storage in the forward compartment under the berth, 1/2 of the storage in the aft section under the v berth, and lost a little room in the v berth closed forward of the galley due to ductwork. However, I am very satisfied with the install. Additionally, I was able to T the head through hull seacock for the A/C unit as well. It turned out to be a nice neat install. Everything hose, duct, and electrical fished through just fine without any headaches. Please let me know if you plan to do an install and want any advice!

Jim
 
So if you use the head with the AC on, does the unit shut down with the drop in water flow?
 
Well, the unit has been installed for a month now and I am so thankful I went with a 16k unit. Although we have not seen many truly uncomfortable days yet, it has performed ok. If I were to do it over again, I may go up a few k in the BTU.

And no, the head does not interfere with the pressure of the AC pump. There is plenty of water in the lake for both and I have not experienced any issues as of yet.

Thanks,

Jim
 
When I installed A/C in my 32 Mariner, I tee'd off the seacock for the head. What I discovered after 2 burned out A/C pumps in 2 yearswas that the A/C pump would pull the water out of the line to the head and then start sucking air and lose prime when the A/C would cycle-never when I was on the boat-always during the week. I installed a shutof valve next to the tee to valve off the head when we weren't using it but that was a pain. I had a new thru-hull installed this past winter-much nicer.
 
I put check valves on both lines, I was worried about that, and had an issue at first, but once the check valves were installed, everything was good.
 
I'd put adding a dedicated thru hull for the A/C on my list of things to do on the hard. If splicing in to the raw water from the head was the way to go, every boat mfg would be doing it to save $$$.
 
I have a 28 ft'er with a 15K BTU unit and in the sun on 90+ degree days, it runs all the time.
To figure out what size you need you need the cubic ft of the cabin area and multiply by a factor of 14.
Example: 6' X 15' X 6'= 540 cubic ft.
540 cubic ft. X 14 = 7560 BTU.
If you have bigger windows and low or no insulation, I would go bigger.
 
I was able to see light thru the cabin top. It was just fiberglass with mouse fur carpet. I recently put 1/2 inch styrofoam type insulation up there with paneling and it helped tremendously. We also added some limo tint and insulated curtains.
Every little bit helps.
 
My 89 Mariner came with a 12,000 btu. Worked great even in the heat of Florida summers.
 
You must log in or register to reply here.
Back
Top