Air conditioning !990 c34, some pictures

[glennd3]

Here are some pictures of a new installation

[glennd3]

The unit is a Dometic 12K turbo. Here are some more pictures. The install is not finished yet but close.

[Noah]

Glenn- congrats. Looks like a lot of work for cool toes in aft cabin.  just kidding! Big impressive job? QUESTION: is that black tank on the right in photo #2 your holding tank? Must be smaller tank than the MK1, as there is no space in my MK 1 to add anything between holding tank and macerator pump, let alone that extra thru-hull and Groco (strainer?) contraption.

[glennd3]

Yes it is the holding tank. Also a vent is in the head.

[glennd3]

Just an update, Today it was warm enough to test the unit. The inside of the boat was 83 degrees and it took 35 minutes to lower the temp to 72. The rear cabin cooled very quickly, the head cooled but not nearly as quick, the main salon was the temp tested and the v birth was the slowest. The v birth was very bright as no blinds were used. If I close the door on both births I cannot hear the unit just the fan noise thru the vent. Main salon has the most noise. I can still adjust the fan speed for each of the 6 fan speed levels, I will leave it on the factory setting for the time being. Also I can set the fan to always be running while the unit is on or stop when the temp is achieved. Installer recommends to have the fan always running.

[Joyride]

 I really like that refrigerator install.  Mine is way back behind the aft water tank and I can just barley reach it from the opening hatch on deck.  I have the walkthru transom and that hatch is tiny.  When my compressor goes I think I'll relocate it to that spot in front of the starboard water tank.

[Hugh17]

Just an update, Today it was warm enough to test the unit. The inside of the boat was 83 degrees and it took 35 minutes to lower the temp to 72. The rear cabin cooled very quickly, the head cooled but not nearly as quick, the main salon was the temp tested and the v birth was the slowest. The v birth was very bright as no blinds were used. If I close the door on both births I cannot hear the unit just the fan noise thru the vent. Main salon has the most noise. I can still adjust the fan speed for each of the 6 fan speed levels, I will leave it on the factory setting for the time being. Also I can set the fan to always be running while the unit is on or stop when the temp is achieved. Installer recommends to have the fan always running.

Where are you located? The 12k AC sounds a little undersized for the Southeast. My boat came with a 12k that didn't work. The PO said it really struggled on hot days so I went with a 16k BTU unit which was the largest physical size I could get in the locker under the port side couch. A PO had removed the holding tank and located the HVAC unit there. My only complaint is the noise, but it's better than the alternative of being too hot.

I do like your refrigeration unit in the locker on the starboard side. I will eventually need to replace mine which is currently located in the lazarette hatch. It's too far away from the frig/freezer and too inaccessible.

Congrats on the installation. You did a great job routing that duct to the forward and aft cabins.

James

[glennd3]

Just an update, Today it was warm enough to test the unit. The inside of the boat was 83 degrees and it took 35 minutes to lower the temp to 72. The rear cabin cooled very quickly, the head cooled but not nearly as quick, the main salon was the temp tested and the v birth was the slowest. The v birth was very bright as no blinds were used. If I close the door on both births I cannot hear the unit just the fan noise thru the vent. Main salon has the most noise. I can still adjust the fan speed for each of the 6 fan speed levels, I will leave it on the factory setting for the time being. Also I can set the fan to always be running while the unit is on or stop when the temp is achieved. Installer recommends to have the fan always running.

Where are you located? The 12k AC sounds a little undersized for the Southeast. My boat came with a 12k that didn't work. The PO said it really struggled on hot days so I went with a 16k BTU unit which was the largest physical size I could get in the locker under the port side couch. A PO had removed the holding tank and located the HVAC unit there. My only complaint is the noise, but it's better than the alternative of being too hot.

I do like your refrigeration unit in the locker on the starboard side. I will eventually need to replace mine which is currently located in the lazarette hatch. It's too far away from the frig/freezer and too inaccessible.

Congrats on the installation. You did a great job routing that duct to the forward and aft cabins.

James

James I am on the Chesapeake. I spoke with the AC guys before I bought the 12K. They said with the new units and refrigerants that the 12 K would work best as it would not short cycle. I have not tried the unit yet in the 90s but I have very good air flow in all 4 vents. The refer unit seems to work well in that location, I cannot hear it running in the salon. 

[Ekutney]

I am also located in the Chesapeake where the days can easily get in the 90's & very humid.  I had a guy from Annapolis Cruise Air, Denny, come by & look at my boat before I even bought the unit & he said a 12K would do fine for the same reasons Glenn referenced.  It has been used for 2 seasons & cools the boat fine, even on very hot days.  I get a good bit of condensation & have the drain pan plumbed to the raw water output.  It also does a good job of warming the boat up in the cooler months.  The unit is installed the same location as Glenn's, Nav locker.  I only have 2 vents, one just above the unit on the top surface of the Nav locker & a 2nd to the aft cabin.  The vent on the top of the Nav locker has the fins adjusted so airflow is directed the top middle of the salon.  I also have 4 fans aboard to move air around, 1 aft cabin, 1 fwd cabin, 2 salon, 1 port 1 starboard.  Airflow helps a great deal making down below comfortable.

[Joyride]

I put in a 16k under the v berth two years ago after the old 12k BTU unit died.  I'm down in St Petersburg/Tampa Bay and sometimes I work all day from my laptop in the salon and its very comfortable.  I usuallly put a towel over the front hatch in the summer though and have dark curtains inside covering the long deck windows.  The 12k I replaced seemed to do just fine too until it died though just saying.   

[glennd3]

An update on the AC. Dometic makes a sound cover for the compressor which I installed. Having put the unit in the nav locker the compressor noise was noticeable while in the main cabin. I installed it today, fairly easily and it did reduce the noise considerably. I am posting this as a follow up for anyone planning an install of this unit in the nav locker that you may want to consider the cover. see attached.

PS hot day on the Chesapeake today , heat index over 100

[JeffG]

Glenn,  What did you use as a manifold/tee/wye to split the ducting to the three different vents? Did that come from Dometic?  And what size ducting did you use to each location? 

/Jeff

[glennd3]

Jeff I believe the splitter is from Dometic and the ducting is 4 inches.

[JeffG]

Thanks Glenn.  Perhaps I'll e-mail Dometic  to see if they can help since all the chandleries and stores around here are closed for a while due to lockdown.   I can see they list accessories on their website for the RV units, but I don't see anything for the marine units.

[glennd3]

I think their website is a little subpar.