Air Conditioner Location for an O'Day 34/35

Jan 27, 2008
3,045
ODay 35 Beaufort, NC
Why is your raw water on the opposite side from the head? My head raw water is port in the locker right next to the head. How is your raw water going to the galley? Mine is fresh water to the galley? Is this all PO mods or did ODay change it up with the model change?
 
May 30, 2006
300
Oday 34 Chesapeake Bay
Sorry if I've caused confusion. The image is taken from the port side which is where the head and galley are located as well. I was planning to install the AC under the starboard settee, however the unit was also too tall there...just didn't post a picture of that side.

Gatr has indicated that there is a lifting ring that can be removed which may reduce the overall height. I've ordered a unit and will take a last look at the starboard settee location. After taking a look at Gatr's pictures, however it's clear that the forward hanging locker is a no-brainer in terms of install and unit accessibility.
 
May 30, 2006
300
Oday 34 Chesapeake Bay
Just received the MSBA14. Gonna start the install this weekend. Still waiting on fittings, vents and the like. I'll attempt to set in the settee storage areas however have less confidence it it fitting in those spaces. Also, the Graco strainer is huge. Kinda makes the one the PO installed in the engine raw intake seem kinda puny.

More to come...
 
May 30, 2006
300
Oday 34 Chesapeake Bay
Did the install over the Labor Day weekend. Took about a day for the complete install. I had assembled all the components before beginning. Two notable issues:
1. The March pump needs to be well below the water line in order for it to have enough positive pressure to get primed. The diagrams show the through hull as being down from the strainer which is lower than the pump. I had to place the pump at the lowest point that I could in order to get the pump primed consistently. Pump, strainer and through hull are all located below the water line on the port side with hose and wiring fished to the starboard hanging locker. Didn't take a picture of this as the strainer and pump are just placed in the area and not secured at this time. I have to do a bit of fabrication to glass in some mounts for both.
2. Drilling the hole through the hull for the raw water discharge was tough. Not hard, but mentally tough. I measured 5-6 times and had a beer before taking a drill to the perfectly good hull. The good news is that the hole came out pretty much where I wanted it. I used a laser level from the head sink thru hull on the port side to a location in the hanging locker on the starboard side to confirm the height. I also opened a thru hull with hose disconnected in order to judge where the water line was from the inside. This angst could have all be avoided by hauling the boat or drilling from the outside in a dingy with a line to heel the boat over.
 
Aug 17, 2010
311
Oday 35 Barrington
So, has anyone considered mounting this underneath the V-berth? I saw a Tartan 3500 the other day with the AC unit mounted there, and it seems to me that this is an excellent plave for such an install.
 
May 30, 2006
300
Oday 34 Chesapeake Bay
Gave the v-berth a thought but didn't study it thoroughly. The return air would be an issue (on my 34) as the holding tank is located there, plus that area is very open to the bilge. Good practice would be to not draw return air from the bilge so you'd have to fab a return air plenum to isolate the return from that area. Supply air ducting would be more of a challenge as well, but doable. Could also be a noise issue as you'd be in effect sleeping right on top of the unit.

I'll take closer look next time I'm at Karma.

An alternative would be to install two smaller units which would be easier to locate with the added benefit that you could run one whilst on the hook.
 
Aug 17, 2010
311
Oday 35 Barrington
My 35 has a Vacuflush generator and the 20-gallon holding tank under the V-berth. It seems that there is still a LOT of room here, particularly on the port side. I would think that a louver could be placed here for the return, and the ducting could easily run along either the port side, between the liner of the head and the hull , or along the starboard side through the bottom of the hanging locker.

I am in Florida and the boat is in Rhode Island right now, but I will take a look at this.
 
Aug 17, 2010
311
Oday 35 Barrington
Still thinking about mounting this A/C under the port side of the V-berth. Another advantage of this location is that I think I could run the condenser drain into the head, because the head and the V-berth share a bulkhead. I'm just thinking out loud mind you... I think that I could position it so that the drain pipe exits under the toe-kick for the sink vanity. Also when/if the water level gets too high, I could simply activate the shower sump.
 
Oct 7, 2008
378
Oday Oday 35 Chesapeake Bay
I wonder if it would pick up any smells from the hoses, fittings and tank that permeate.
 
Aug 17, 2010
311
Oday 35 Barrington
There is no smell in that area now, and I would think that any air flow would only decrease the likelyhood any developing.
 
Aug 17, 2010
311
Oday 35 Barrington
I checked my proposed location out yesterday, and it won't work. I forgot about that little storage space between the V-berth and the bulkhead. While that provides a great place to hide your shoes, it prevents a direct connection between the V-berth and the head.
 
Sep 23, 2009
1,475
O'Day 34-At Last Rock Hall, Md
I know I am re opening an old thread but finding room in the 34 seems to still be a challenge. I don't think the admiral would be very happy with losing the hanging locker. Last weekend I took some cardboard mockups to the boat concluded that the areas under settees are too small. The forward hanging locker is tight but doable. However I wonder if the rear wet locker and chart table area behind the two small drawers might be an unused area that would work. It would require disassembly of the chart table and not sure how the ducting should be done.
Any thoughts? 14000 or 16000?
 
May 30, 2006
300
Oday 34 Chesapeake Bay
Easiest install is the forward hanging locker. From there you can easily duct into the v-berth (4" duct) and the saloon (6" duct). The louvered doors of the locker are adequate for the return, however I ended up a return grill with filter there just to be sure. There is a filter on the unit itself so that's probably not needed.
Go with 16K BTU. Mines a reverse cycle unit which is ok until the water temp gets below 40 degF.

IMG_2920 (2018_12_12 06_10_03 UTC).JPG
IMG_2924 (2018_12_12 06_10_03 UTC).JPG
 
Sep 23, 2009
1,475
O'Day 34-At Last Rock Hall, Md
Scott, thank you for the great pictures.
Looks like the locker becomes pretty much unuseable? Would the 6 inch duct fit along the hull to exit at the shelf behind the settee? Unfortunately we store a lot of stuff in that locker and are reluctant to lose it. Also wondering if a split system with air handlers like those used in power boats might be an option.
 
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May 30, 2006
300
Oday 34 Chesapeake Bay
Yes it pretty much consumes the locker. The transition and duct work take up a good bit of space. The MA system that I have allows for 360 degree rotation of the blower, so there are multiple options to route the duct work. My goal was to eliminate as much opposition to the airflow as possible so I wouldn't have to worry much about insuring an adequate air flow.

Haven't studied split systems so can't really comment. One school of thought is to install two smaller units. Other than giving you more options for install space, individually they take less power to operate which gives you the option of running one unit of a generator.
 
Aug 9, 2023
5
O'Day O'Day 34 Chesapeake Bay
Hey folks - just purchased a 1984 O'Day 34. Bringing her down to the Chesapeake next spring. Installing AC. Trying to determine the right/appropriate size (BTUs). Folks up in New England indicated as low as 8000 BTUs but I saw on this forum twice that. Obviously, oversizing the unit can create many issues. The Dometic units will fit below the settee but they are more expensive. Any input on the appropriate rating for this size boat in the Chesapeake?
 
May 30, 2006
300
Oday 34 Chesapeake Bay
@Madisoncay Welcome as well. I'm at the mid bay area and 14KBTU works well for me. I've fed a 4" insulated duct to the v-berth which keeps it cool as well as the louvered vent that you see in the above pictures which is fed by a 6" duct with a transition to rectangular vent. 8KBTU would probably work, however I suspect that you'd have to close the door to the v-berth to reduce the overall volume to be conditioned.
 
Aug 9, 2023
5
O'Day O'Day 34 Chesapeake Bay
Thanks! I know it was an old thread but it was O'day specific, so I went with it. Somewhat leaning toward a larger unit and sacrificing the hanging locker to have comfortable sleeping conditions both forward and aft. The previous owner(s) had an undersized Mermaid unit and the duct work was all wrong. I believe I can make use of the water pump from the previous system but will need/want to set up the split discharge to the v-berth and saloon. Have replaced the teak toe rail and eyebrow, head, holding tank, hot water tank, all thru-hulls, standing rigging and will replace hoses, belts and pumps on the engine. Adding solar to charge batteries and new refrigeration. Grew up sailing Buzzards Bay and the Vineyard. Excited to explore the Chesapeake - appreciating the lack of wind during the summer.