I am still trying to figure out the best place to install a Marine A/c unit in the boat. I also need to know how to run the ducts. If anyone has some photos showing the installation on the A/C unit and ducts I would certainly appreciate all the help I can get. Is a 9k btu unit big enough to cool the boat adequately in florida? Thank Again this forum and the people are GREAT!!!!!!
H31 Air Conditioner
- Thread starter margaritaville
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H31 A/C Solved!
In 2005 I installed a 12K in my H31 in the hanging locker on the port side across from the head. Works GREAT, neat and simple. I cut out the bottom of the closet, installed the water intake, filter,and pump below the water line. Put plastic 2x4's on sides above the water line to set unit on. Cut the outgoing water through the side of the boat. For supply air cut a hole in the top of the cabinet and built a box to hold the register. Also cut a 4" hole for a supply air into the v-berth. Attached filter directly to the unit and cut 12 x 12 out of door bottom to mount return air register. I Noticed you are in FTB, if you want to arrange to inspect my install e-mail "billsail@bellsouth.net" would love to show it to you.
In 2005 I installed a 12K in my H31 in the hanging locker on the port side across from the head. Works GREAT, neat and simple. I cut out the bottom of the closet, installed the water intake, filter,and pump below the water line. Put plastic 2x4's on sides above the water line to set unit on. Cut the outgoing water through the side of the boat. For supply air cut a hole in the top of the cabinet and built a box to hold the register. Also cut a 4" hole for a supply air into the v-berth. Attached filter directly to the unit and cut 12 x 12 out of door bottom to mount return air register. I Noticed you are in FTB, if you want to arrange to inspect my install e-mail "billsail@bellsouth.net" would love to show it to you.
Not solved!
The problem is not solved. I would perfer not to use the hanging locker since that is the only usable hanging locker. It seems to me there must be a better spot to place it where some ac ducting can be place to evenly distribute the heat or cool air.
The problem is not solved. I would perfer not to use the hanging locker since that is the only usable hanging locker. It seems to me there must be a better spot to place it where some ac ducting can be place to evenly distribute the heat or cool air.
Locating your AC...
I put my AC in the starboard cockpit locker just forward of the fuel tank. The return air grill is cut out of the center wall of the aft berth. The main duct runs along starboard over, under, around and behind the hot water tank, ice box, one of the sliders, banquet seats down into the storage area under the forward bench of the banquet seating where an exit grill is installed just aft of the head entrance blowing out into the center isle of the saloon. Numerous other small vents are located along the cornices on both sides of the main saloon, v-berth and aft berth. This system creates excellent air circulation.
I put my AC in the starboard cockpit locker just forward of the fuel tank. The return air grill is cut out of the center wall of the aft berth. The main duct runs along starboard over, under, around and behind the hot water tank, ice box, one of the sliders, banquet seats down into the storage area under the forward bench of the banquet seating where an exit grill is installed just aft of the head entrance blowing out into the center isle of the saloon. Numerous other small vents are located along the cornices on both sides of the main saloon, v-berth and aft berth. This system creates excellent air circulation.
great idea
Sounds great Doug! I like it very much. What size A/C unit did you use? Where did you attach the raw intake? Did you use the engine thru hull or did you use one dedicated to the unit? I don't suppose you could get a photo of the installation and the vents inside the cabin? You have been a great help. Thank you.
Sounds great Doug! I like it very much. What size A/C unit did you use? Where did you attach the raw intake? Did you use the engine thru hull or did you use one dedicated to the unit? I don't suppose you could get a photo of the installation and the vents inside the cabin? You have been a great help. Thank you.
Your questions...
It has been several years since the installation. Long enough that I cannot remember the details of capacity. The raw intake comes through the main engine intake and I have a set of valves installed that allows me to direct the flow as required. The valves are mounted forward, bottom port, in the engine tray accessible by removing the steps. The AC capacity and pictures could be made available however, it will be six weeks before I am at the boat.
It has been several years since the installation. Long enough that I cannot remember the details of capacity. The raw intake comes through the main engine intake and I have a set of valves installed that allows me to direct the flow as required. The valves are mounted forward, bottom port, in the engine tray accessible by removing the steps. The AC capacity and pictures could be made available however, it will be six weeks before I am at the boat.
H31 in Hanging Locker
I purchased my 12 BTU Marine Air unit from a friend, then designed the install around the units requirements. I read and reread the installation instructions about the water flow uphill to the unit through the filter and pump. System wanted the pump to be at least 12 below the water line, which is bit hard to do on the H31, or install a reservoir to feed the system (mine required 500 GPH flow). I shot a laser level throughout the boat at the waterline to find the best location for water intake. My system does eliminate the hanging locker, but it was simple, easy, and provides flow through out the boat interior and vberth. Only 6 inches of duct to get out the top of the locker and 12 inches to get to the vberth. No long runs of intake or outflow of water lines. Works great. I have owned my boat for 6 years have taken week long cruises and never used the locker for more than storage, so giving up the locker space was not hard for me. I would not want to give up the space in the starboard locker. Recently I had to remove and reinstall the fuel tank, I needed all of the starboard locker space to move around in and had to cut out the back 1/3 of the divider between the port berth. If you have to replace the 2" exhaust hose that exits behind the fuel tank, how will you get to the hose clamp? Also I recently installed refrigeration and put the cooling unit it the starboard locker. Maybe you might want to go to the Marine Air website and download the installation manuel for their units and get some insite into the recommend installtion requirements and methods.
I purchased my 12 BTU Marine Air unit from a friend, then designed the install around the units requirements. I read and reread the installation instructions about the water flow uphill to the unit through the filter and pump. System wanted the pump to be at least 12 below the water line, which is bit hard to do on the H31, or install a reservoir to feed the system (mine required 500 GPH flow). I shot a laser level throughout the boat at the waterline to find the best location for water intake. My system does eliminate the hanging locker, but it was simple, easy, and provides flow through out the boat interior and vberth. Only 6 inches of duct to get out the top of the locker and 12 inches to get to the vberth. No long runs of intake or outflow of water lines. Works great. I have owned my boat for 6 years have taken week long cruises and never used the locker for more than storage, so giving up the locker space was not hard for me. I would not want to give up the space in the starboard locker. Recently I had to remove and reinstall the fuel tank, I needed all of the starboard locker space to move around in and had to cut out the back 1/3 of the divider between the port berth. If you have to replace the 2" exhaust hose that exits behind the fuel tank, how will you get to the hose clamp? Also I recently installed refrigeration and put the cooling unit it the starboard locker. Maybe you might want to go to the Marine Air website and download the installation manuel for their units and get some insite into the recommend installtion requirements and methods.
Looking at the same thing
I'm looking at installing mine under the aft dinette seat as one post suggested. I'm going to use the thru hull that was originally for the waste holding tank discharge for the intake (can't use that in Lake Michigan anyhow -thinking of using the sink drain outlet for the AC outlet - Looking at mounting the pump under the sink in the head - haven't quite worked the details out. I'm thinking I can route the ductwork to discharge into the cabin by cutting vents on the cabin side of the dinette seat. Mine is a 6.5K Mermaid (doesn't get humid here like Florida).
I'm looking at installing mine under the aft dinette seat as one post suggested. I'm going to use the thru hull that was originally for the waste holding tank discharge for the intake (can't use that in Lake Michigan anyhow -thinking of using the sink drain outlet for the AC outlet - Looking at mounting the pump under the sink in the head - haven't quite worked the details out. I'm thinking I can route the ductwork to discharge into the cabin by cutting vents on the cabin side of the dinette seat. Mine is a 6.5K Mermaid (doesn't get humid here like Florida).
A/C Unit Below Water Line?
When I consulted a Marine Air Distributer, they suggest not putting the unit below the waterline. Because salt water would stay in the unit. By mounting unit above the waterline and the discharge hose with a natural downward slop that discharged lower than the bottom of the unit, the seawater in the coils would drain out when the unit was turned off. Results in less corrosion. Tha is the arrangement shown in their installtion manuel which can be printed from their web site. In my 1987 H31 the level of the head discharge would be above the cooling water intake, requiring a reservoir tank to feed the seawater in the cooling coil, requiring more space and complexity. On my 1987 H31, the waterline is at the top of the wood of the dinette seats.
When I consulted a Marine Air Distributer, they suggest not putting the unit below the waterline. Because salt water would stay in the unit. By mounting unit above the waterline and the discharge hose with a natural downward slop that discharged lower than the bottom of the unit, the seawater in the coils would drain out when the unit was turned off. Results in less corrosion. Tha is the arrangement shown in their installtion manuel which can be printed from their web site. In my 1987 H31 the level of the head discharge would be above the cooling water intake, requiring a reservoir tank to feed the seawater in the cooling coil, requiring more space and complexity. On my 1987 H31, the waterline is at the top of the wood of the dinette seats.
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