Time for new AC.

Jul 23, 2009
857
Beneteau 31 Oceanis Grand Lake, Oklahoma
About one month I managed to get the Cruisair 12,000btu turbo air conditioner working on my new to me Beneteau 31. Last week I left the unit on dehumidify mode. The unit should have ran for about 30 minuets every 12 hours, so not a lot of run time. Yesterday when I got to the boat and turned the AC unit to cool mode the compressor started making a loud rattling noise and it did not cool at all. I'm done working on this thing, time for a new unit.

The space that I have to work with is odd shaped and a normal unit with a square drain pan won't fit, so I'm thinking about another turbo unit. I would also like to take this opportunity to upgrade to a 16,000btu unit. It's slightly bigger in ever dimension but I think I can deal with this.

Any suggestion?
Good place to purchase from or avoid?
 
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Feb 21, 2013
4,638
Hunter 46 Point Richmond, CA
You have some AC options as discussed in this article. 10 Best Marine Air Conditioners Reviewed and Rated in 2020

My local marine guys recommended a Dometic DTG 16000 btu unit with optional sound cover. Dometic sells an EDC and EDC models. The ECD dimensions are: 13.5 in, high, 20 in wide and 11.5 in deep and the higher cost DTG dimensions are: 13.4 in high, 21.4 in wide and 13.3 in deep. However, I would want to understand if the added cost for the DTG unit is worth it. This project is currently on hold until I install a dedicated thru hull for the raw water intake during my next haul-out.


You generally purchase one from the AC manufacturer's dealer. Let us know what you finally installed and why and whether the unit was self contained, whether it came with a raw water pump or not and how the noise level was.
 
Jul 23, 2009
857
Beneteau 31 Oceanis Grand Lake, Oklahoma
I've tried contacting several dealers and their phones are disconnected, later I noticed that their web sites were also down. I'm guessing they are out of business due to the pandemic.

I did find a dealer with a reasonable price on a DTU but they are sold out with no idea when a new shipment will arrive. This guy took the time to call me back and leave me a message, I'll probably do business with him if things ever return to normal.

Unless I move the AC unit to a new location or replace it with a split unit I'll have to replace it with another DTU (Dometic Turbo Unit). I really don't want to work that hard. I would happily modify the duct work and the mounting in an effort to replace the original 12k btu unit with a 16k btu unit. Space is at a real premium on this boat.

The pump I have should support the larger 16k unit.
 
Feb 14, 2014
7,399
Hunter 430 Waveland, MS
Any suggestion?
Call Dometic directly with your old unit model/serial number and perhaps your available space dimensions.

I called them on my recent change from 16k MarineAiree, the Tech gave me the perfect placement Unit#. In fact I have extras space and the install took 3 hours.

All of the Techs I have talked with [4 ] are superb. Gave me great info on even replacement part numbers and where to buy them.
Jim...
 
Feb 14, 2014
7,399
Hunter 430 Waveland, MS
However, I would want to understand if the added cost for the DTG unit is worth it
I recently installed the ECD 16k unit. Plus I replaced my old 7k MarineAiree with a 8k DTU unit in 2015.

I also looked at the 16k DTU and the Dometic Tech told me to go with the ECD. I was most concerned about noise. I can barely hear my new ECD.
The ECD unit is a complete package for all components [Controller, cable, Display, Power unit]. The DTU does not.
No contest for me.
Jim...
 
Jul 23, 2009
857
Beneteau 31 Oceanis Grand Lake, Oklahoma
When I was working on the old DTU it took me a week to get through to a tech at Dometic. I finally started calling every 1 to 2 hours, the operator was very helpful but she couldn't get a tech to answer the call or return my call. Near the end of the day I requested a manager, but never did get to talk to one. A tech did finally call me, he was very helpful. The tech went to far as to give me a direct line and his email, but when I tried contacting him with another question I didn't get an answer. This was very frustrating. It shouldn't take a week to get through to a tech.

I'm gonna take some better pictures of my space available along with some measurements. Then I'll call Ocean Breeze.

I haven't given up on the DTU though.
 
Mar 3, 2003
710
Hunter 356 Grand Rivers
I’m in the same boat with my 2003 H356. My unit quit working about 3 weeks ago. Tech from Dometic gave me some tips on what to check, but I’ve not had time to go try it. I’m probably going to just replace. New unit isn’t that expensive and HVAC mission critical for both me and wife. After 18 years and 1204 days on the boat plus several full time winter heating seasons, I think it’s time to retire the original unit. Looks like the biggest issue will be having to make the duct connection as my unit had the compressor on the right and the new ones are on the left looking aft. That puts the blower further port than original so will need to fabricate a connecting piece of ductwork. Shouldn’t be that big a deal. I’m going to replace my HVAC water pump at the same time.
 
Jul 23, 2009
857
Beneteau 31 Oceanis Grand Lake, Oklahoma
Jerry,

Probably a good idea to replace the pump, it sounds like it has a lot of time on it.
My unit had almost no run time on it. The diesel only had 77 hour when I bought it and the owner said he never used the AC, I don't think he even knew to open the valve to the water pump.

What is the original unit doing?
 
Mar 3, 2003
710
Hunter 356 Grand Rivers
I left it running all winter and I monitor by web cams on board. Early spring I started having issues with what I thought was the reversing valve. I would check it regularly and on days when the temps might get close to set point or above when it might reverse to cool, that night it might go down to high 50’s. I would check during the day and most times it self corrected, but occasionally I would have to go to the marina and tap on controlmpanel and the reversing valve and it would reenergize the compressor and get back to normal. It got more frequent as late spring approached. I had air flow and water flow but the compressor was not responding. About 3 weeks ago, I saw temps were off and went to marina. Had no water flow from pump, fan was running, but couldn’t get compressor to start. Cycled a couple of times with breaker and switch and then fan no longer worked either. Let it sit a day, went back and nothing. Been traveling and fairly busy so just now back on it. Talked to Dometic and gave some things to try, but I think it’s just time to replace even if I can get it going.
 
Jul 23, 2009
857
Beneteau 31 Oceanis Grand Lake, Oklahoma
Jerry,

You may have damaged the compressor due to lack of water flow. I bet the compressor restarted many times. It's possible that the capacitor and/or the start device (probably a ptcr) failed. These are easy and cheap to replace.

I will soon have an extra control board. I hope to remove the old unit soon, but it's been too hot lately.
 
Jun 21, 2004
2,532
Beneteau 343 Slidell, LA
Replaced a relay circuit board in mine two years ago. Pump wouldn't run and of course compressor didn't run. Looked inside the circuit board housing and noted that the relay had shorted. New one was approximately $50. Plug & play and everything has worked fine since then. With most newer units, the circuitry will shut off the compressor if there is insufficient water flow, overpressure, underpressure, etc.
But, I agree with you, at 18 years, your system has seen better days.
 
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Jul 23, 2009
857
Beneteau 31 Oceanis Grand Lake, Oklahoma
I forgot to post the solution to my AC problem here. I should have updated this thread a long time ago.

I purchased a new Dometic Turbo Global unit from Wright Marine. They were very helpful.

The new unit was 1 inch bigger in every dimension. I had to raise the floor in order to get the width that I needed due to the shape of the hull. Then I had to put a small notch in the seat bottom due to the new height. Basically everything else was plug and play. I eventually increased the main discharge duct from 4 inches to 5.
So far it been great.

My old unit would start/run with my Honda 2200 but I haven't tried this unit yet.
 
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Feb 14, 2014
7,399
Hunter 430 Waveland, MS
My old unit would start/run with my Honda 2200 but I haven't tried this unit yet.
It is the LOCK ROTER AMPs

You have to exceed normal Amps to start it up.

I have the Dometic Turbo 8K Btu and it is very quiet versus the old MarineAire 7k unit.

Just a momentary burst in Amp flow to start the compressor.
Jim...
 
Jul 23, 2009
857
Beneteau 31 Oceanis Grand Lake, Oklahoma
It is the LOCK ROTER AMPs

You have to exceed normal Amps to start it up.

I have the Dometic Turbo 8K Btu and it is very quiet versus the old MarineAire 7k unit.

Just a momentary burst in Amp flow to start the compressor.
Jim...
I haven't tested it yet. Maybe this weeked.
 
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Jan 17, 2013
439
Catalina 310 St. Simons Island, GA
New Dometic units are much more compact and efficient. I also had a SmartStart installed on mine so it will run off my Honda 2000 generator. Mine is also 16,000 BTU
 
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Mar 26, 2011
3,399
Corsair F-24 MK I Deale, MD
If you don't have space, look at improving insulation, window covers, and perhaps an awning. There are advantages to the lower amp draw of a small unit. Quieter. Better dehumidifying than a larger unit.
 
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