Dometic Durasea Review

C

C-Nile

New member
I wanted to establish a thread on our ongoing use of the Dometic Durasea A/C unit. Noise level from three feet away from the unit outside—it’s only 75 dB. Inside the cabin noise level is between 75 dB and 80 dB. However, the noise is low pitched. My wife and I can have a normal conversation with it running.

With the unit mounted in the ceiling, it easily provides a robust flow of air into the berth.

It is a powerful unit, so we found we needed to be careful with not having too much airflow directed into the cabin directly around the unit or else the unit will cycle on and off more frequently because it sucks in the colder surrounding air, satisfying the thermostat too early. This of course was expected, because it is twice the capacity that we needed, or is it? We’ll know later in the year.

The one thing we don’t like about the Dometic is that the fan can’t be cycled off when the thermostat is satisfied.

The optional heating element in the unit does a good job of taking the morning chill out of the air, but it is not intended for continual use, and the manufacturer states this to be the case. We use a Caframo RV heater for continual usage in cold weather, which has 600, 900 and 1200 Watt settings.

We keep the Durasea covered when not in use. We purchased it from Amazon for $17: “Classic Accessories RV AC Cover, White, For Coleman Mach I, II & III, Mach 3 Plus, Mach 15, Roughneck & TSR.” It fits well and stays in place even while under way and traveling at 28 mph.

So far, it seems to be working out well. We are waiting for more extensive usage in hot weather, and will report our findings at that time.
 
C-Nile,

This thread is something that I can relate to.

On my 22' C-Dory Joan and I traveled a bit during the summer with no A/C. At anchor, life was good, but tucked up in a dock at a marina was tough. as little to no wind and if there was any, it was not blowing in a direction to be helpful.

After a bit of suffering, I purchased a small window A/C unit to fit into the forward center window. It worked well, once installed and it was wonderful to have a nice climate on a 97 degree day, while tied up at a marina. Problem was, installing the A/C on the small deck of the 22, after a long day of cruising 60 - 80 miles, I was tired. Once moored, trying to safely get the A/C into the center window, became troublesome. After almost loosing the A/C overboard and dropping the GFI outlet into the water, we had had enough.

Life of cruising became MUCH better after I installed a rooftop A/C with the heat strip. I purchased the low profile Coleman Mach 8, 9,200 BTU unit. I chose this, as it would be easy to power with a small Honda inverter/generator. We found that we had to keep the cool setting low, as it made the cabin cold quickly (even with out camper back and rear door open). We also found that the heat would run us out of there in the winter, if we did not keep it on a low setting as well. Like you, we found that the noise of the fan outside was LOUD. but the noise inside was very reasonable. We made sure that if we moored at a marina, we positioned our boat a long way away from others that relied on natural ventilation.

We now have a 26 with a built in A/C and a built in electric heater. This A/C does not make a lot of noise, but it is saltwater cooled. The drain for condensation goes to the aft cockpit. I am not fond of having my feet in cold water, while relaxing with a cocktail on the rear deck, so I must find a solution. If I can't get the condensation issue manageable, I will remove the A/C unit (which takes up a huge section of the aft port storage compartment) and install a low profile air cooled rooftop unit (with a heat strip).

When I worked on rescue boats in the Coast Guard, we did not have A/C. On ships we had A/C, but as the Chief Engineer of many ships this was something that did require a staff to keep everything running smoothly. Years later, while working for the Corps of Engineers, I found that the rooftops were the BEST solution for small boats. We had them on all of the small survey boats. I never had sea water leaks, pump failures, condensation in the cabin or the cockpit. If the unit failed, I could buy another one and have it installed within several hours.
 
We have used the 5,000 BTU window type of air conditioner on two C Dory 22's and two C Dory 25's. On our current boat, we have added handles to the side of the steel case of the ac unit--and that makes it far easier to handle. One of the prior owners had made wooden runners for the bottom of the window air conditioner, and that makes it far easier to handle. we put some squares of left over Decadence vinyl loop material to avoid scratching the ledge over the entrance to the "V" berth. We also have a carry bag, with a padded bottom, and handles on the "Carry bag"--this slides nicely under the V berth.

We had the Coleman 9200 BTU unit on our Tom Cat. My album has several photos of the installation, and modification of the cabin top--which makes a better installation. We are considering putting a Coleman 9200 BTU AC on the current boat. The reluctance, is that it then becomes a little harder to carry our 9 1/2' inflatable on the cabin top. The 5000 BTU is plenty, even on the hot Florida weather as long as there is some shade, and we use Reflectx (mylar bubble wrap for Lowes) in the windows. It will bring the temperature in the cabin to about 20* below ambient. We generally do not use the AC when under way--but having a cabin top unit (the Coleman 9200 BTU will allow us to run with the AC on. The 9200 requires a Honda EU 2000i. The 5000 watt unit will run with a Honda EU 1000i.

It would be nice to have a way to take the RV AC unit easily open and off. That could be achieved with our crane davit. But the RV opening is 14" square, and most marine hatches are 12". It would be fairly easy to make an "adaptor" to fit over the 14" square hole with Starboard--either with or without an opening hatch.

The reason we have not used the "built in" water cooled units are several fold:
They take up a lot of room--the compressor, the raw water circulating pump, and the duct work.
They have a condensate which must be removed (by drain or Venturi effect).
The marine water cooled units cannot be used when "boater homing"--which we do often when traveling to our on the water destinations....
Maintenance is high higher with the water cooled unit: an extra pump, strainer, and water intake--any of which can fail or become plugged.

Several--options all of which will work. Cheapest is the window units at $139...
RV units in the $800 range and sea water cooled least expensive in the $ !500 price range.
 
Thank you for your feedback, Steve. Now we are really happy we did not go with a water cooled unit! You provided more reasons for not going that route.
Like you, we started with a 5K portable, but I got tired of lugging it around, and did not want to construct a box to placed it over the hatch.

Frankly, I am a little concerned about noise at night in a crowded marina—we’ll see. The portable unit was not bad at all, but this Dometic is a substantial unit. On the other hand, the constant trickling of water from water-cooled units makes noise, too, so fair is fair.

So far, it does not seem to be over-kill for our boat. We are in full sun, and even with the superior insulation afforded from Mascoat Delta-T, it is quite a heat load. We need to wait for hot, humid weather to arrive before we can get a good idea how well it works.

Dr. Bob could well be correct on using RV units for our boats. The most expensive option is not always the best. It is complicated. We bought a top-of the line 21 SEER Lennox A/C unit for our house, and it crapped out after 9 seasons. That extra money only bought us high efficiency. The other thing is that Lennox uses proprietary parts that can drive up the costs for repairs. When it was working, the Lennox was a great unit. How is Dometic on repairs? How long will it last? So these days, who knows how long anything will last? The only thing we can all do is to report our findings and see what transpires over time so that others may profit from their benefit of our experiences.
 
How is Dometic on repairs? How long will it last?
Click to expand...

No one knows how long it will last...but I know of RV units which have lasted many years--on our last RV 12 years going full time over 6 months out. of the year--and some years all of the time. Still going strong when the unit was sold recently...

As for Dometic repair...if the repair on the their refer/refrigerators, is any indication--probably not so good.. (We have had two units go out just after the 2 year warrantee was up--repairable--but Dometic would not do it. Most techs just say "replace". .Sometimes the repair costs as much as the unit.

Hopefully the "marine unit" will run for 20 years...
 
thataway":1vf4132j said:
How is Dometic on repairs? How long will it last?
Click to expand...

No one knows how long it will last...but I know of RV units which have lasted many years--on our last RV 12 years going full time over 6 months out. of the year--and some years all of the time. Still going strong when the unit was sold recently...

As for Dometic repair...if the repair on the their refer/refrigerators, is any indication--probably not so good.. (We have had two units go out just after the 2 year warrantee was up--repairable--but Dometic would not do it. Most techs just say "replace". .Sometimes the repair costs as much as the unit.

Hopefully the "marine unit" will run for 20 years...
Click to expand...

Good input Dr. Bob. I’ll tell you this: if the Dometic fails after a short time, it will be replaced by a an RV unit. There’s no way I’m going to pay $2800 for a new unit or an expensive repair to our existing unit.
 
We continue to love our Dometic air-conditioning unit. At first, I and others felt that a 15,000 BTU air conditioner was too big for this boat. After using it throughout the summer, I would say it is the minimum we would want under the present circumstances. Our boat is docked pointing dead north, which means we get full sun on the sides of the boat throughout the day. The heat load is significant, and the way the air-conditioning works, the compressor runs approximately 1 1/2 minutes on cool and then cycles off (but with the fan running) for up to 4.5 minutes (my guess is so it won’t short cycle.). The fan remains on constantly. The coils never froze up even in the most humid conditions. The unit brings the inside temperature down to a comfortable 68° and it does a great job of removing the humidity from the air. On the outside, I measured approximately 55 dB sound level, and asked my marina neighbors as to whether or not they found the sound objectionable — all people said that the sound level was barely noticeable if noticeable at all.

I bought an inexpensive air conditioner cover for the Dometic and found that even at 30 miles an hour, the cover stayed in place, which prevented Saltspray from entering the unit. The reason I mention this is that for those who would use a far less expensive, non-marinized, RV unit as DR. Bob has suggested, this would be a good way to protect the unit while traveling in salt water. I think the Dr. Bob may be onto something when recommending these cheaper RV units, and if I were to do it over again, I would probably choose that path. However, after using our 15 K unit over the summer, I wouldn’t go any lower than 12 K if I wanted to keep the interior down to 70°
 
Thanks for the review of the Dometic Marine unit. Good to know it keeps you cool in the Northern climes.

Not sure what the ambient temp. is on Long Island Sound, but our 5,000 BTU window unit keeps the cabin at the mid 70's when daytime temp outside is in the 90's. But there are a few little tricks I use. Biggest heat loss is the windows. We have pieces of Reflectix (silver mylar coated double bubble material) cut to fit each window, including the door. (And this is a C Dory 25, not a 22. so a little larger cabin) We also have fairly heavy fabric curtains, which roll down. Another trick is to have a low speed fan at the floor, near the aft cabin, which will put the cool air back up to the upper part of the cabin. Also , we have a "Reflectix diverter" over the top of the window AC unit--that directs the air aft, rather than up, as the vents tend to do. During the heat of the day, the AC is running 100% of the time. To compare: the RV 15,000 Dometic runs about 75% of the time on a 25 foot RV. Both of these units are quiet. I cannot tell if they are running from 10 feet away from either the boat or RV by sound. (OK I have some hearing loss, as I have aged.). On the subject of aging, we have a nice Terry cloth carrying case for the window unit, with a hunk of 1/2" neorpeme foam on the bottom. We put handles on the side of the window unit--and recently rigged up a block and tackle from the bottom of the re-inforced (two pieces of 1 " aluminum angle bolted across the shelf over the forward part of the cabin. The block and tackle allows one person with limited to lift the window AC into place, and then swing it forward thru the open front window. We use the same spreader bar we use for hoisting the inflatable aboard. We just added two more eye bolts, equal distance to the outer part of the handles on the side of the unit.

There is no question that the roof type of AC is better. We decided against it, because we carry a 9'6" dinghy on the roof. The second reason, is that although we have a 2200 Watt Honda generator, the 5,000 BTU window unit will run on a 1000 watt generator, and we can charge batteries, heat water (with out new Bosch 2.5 gallon water heater under the galley sink) and even run the microwave (one or the other) with the generator running. There is no necessity to use an "Easy Start" on a larger RV air conditioner.
 
Dr. Bob,
Off subject, but please tell me more about your water heater. My 6 gallon, huge box shaped water heater takes up way too much space.
Am exploring the marine Isotemp 4.2 gallon water heater, to improve available storage space.
Steve Baum
Homeport of Portsmouth, VA
OSPREY (Ex Mister Sea) 2000 22 C-Dory 2010 - Sold 3/19
OSPREY (Ex ADITI) 2007 26 Cape Cruiser 2018
 
srbaum":pe40qazx said:
Dr. Bob,
Off subject, but please tell me more about your water heater. My 6 gallon, huge box shaped water heater takes up way too much space.
Am exploring the marine Isotemp 4.2 gallon water heater, to improve available storage space.
Click to expand...

Steve, I have been wanting to get rid of the big water heater for a long time. Even went to the trouble of removing it in my first 25. But the instant flow heater did not stand up to the pressure of the system. I made mock ups of several others, but they took up too much space under the galley. Micah Curtis of the C Dory 25 Sierra had posted that he put a 2.5 gallon Bosch outboard of the sink in a 25. I wasn't sure it would fit, because I have a lot of electrical cables back there (bundled and supported). So I made a mock up--looked like it would work. The heater is about 10" deep, 13.75" wide, and 13.75" high. This is a little misleading, because there is a pressure relief valve, and then when you put el's on the top pipes, it all shakes out to be about 16" high. But there is room to put it outboard of the galley. The 4 gallon model is 13.75 inches deep--not sure there would be room between the sink and hull (cables and wires).

I made a 1/2" plywood, saturated with epoxy resin, platform about 3" off the shelf under the galley. Legs on the aft end, and and put a cleat on the forward bulkhead under the galley, to support the front of the platform. I could have made the platform a little smaller, cutting it to follow the contour of the hull. There were 4 hoses coming from under the head, to cold water (to shower and to galley) and there was a "y" which spit the hot water from the tank, to the shower (mixing valve in our case) and to the sink. I eliminated that Y, and Ted off the hot water feed of the tank. to the galley, and to the head shower. I left the two cold lines, but may a "Y". One leg to the mixing valve, and the other leg to the cold water side of the shower. Normally we would use only the "hot" faucet in the shower--since we have a set temp at the mixing valve. (40* C currently) and the Bosch tank set on its max 145* F. The recovery rate is about 6.8 gallons an hour with a 1440 watt heating element.

I feel that the 2.5 gal is plenty of water for the two of use to take our "normal" boat shower. (We don't use much more than a gallon each). Mitch says it holds the temp well over night. We will be putting it to the test in the next month.
Here is a link to that 2.5 water heater on Amazon.
 
thataway":nklmu52w said:
Biggest heat loss is the windows. We have pieces of Reflectix (silver mylar coated double bubble material) cut to fit each window, including the door. (
Click to expand...

Thanks for all of your feedback Dr. Bob, and you are dead on with respect to the massive heat gain attributable to our windows. Your suggestion of using Reflectix is a great one. Coincidentally, my wife and I were discussing on Thursday what could be done to minimize the heat gain specifically on the port side of our boat, which faces west. We were bereft of practical ideas, so thank you again, because now we will be using Reflectix.

We use our boat in New England through November; it get’s pretty cold up here. Not only will your recommended material be beneficial at abating heat gain, but it will minimize heat loss on cold New England nights.

The nice thing about the Dometic is that we have complete control over how we direct the airflow. Over 50% of the flow is directed toward the berth, and the remaining flow is directed toward the sides. Our cabin is much smaller than your boat, so I’m not sure that a small fan at the floor is needed, but, it’s worth a try.

Thanks again,
Rich
 
Dr. Bob,
Thanks for providing details about your new water heater. With that info, I too will make a mock-up and test the existing space for fit.

Rich,
I learned about the reflectix (reflectixinc.com my order was for roll part number BP48025) from Rob and Mary from their experiences on their Venture 23 FREEDOM. I purchased a roll and cut pieces for each window and hold them in place with several simple wood pattens. Also I cut pieces to line the port and starboard side of the v-berth. My little 9000 BTU could barely hold its own, but once I placed the reflective material in place, life got a lot better...
Steve Baum
Homeport of Portsmouth, VA
OSPREY (Ex Mister Sea) 2000 22 C-Dory 2010 - Sold 3/19
OSPREY (Ex ADITI) 2007 26 Cape Cruiser 2018
 
The sun beating on the V berth "cave" makes a good heat sink. The fiberglass seems to retain the heat. We put 1/2" to 5/8" back packing pads on the hull up to the shelf. Marie had me put from the shelf to the deck on part of her side. Probably lining the entire V bunk area with some insulation would be a great idea.

We also have fans on both sides of the boat pushing air into the V bunk area. (The entire port bulkhead has been removed, so the V Berth area is open, as it is in the Tom cat. But there is no way with the window unit to direct the flow into the forward/V bunk area, except with fans. We have noted that in the next few weeks, the evening temperatures are going to be in the 50's along the Tennessee River. So the heater is also stowed away...
 
I have a window AC unit in the center window. I also have a 10' fan that hangs in the entrance to the V-berth when we sleep (no cutout). It works very well.

Having the small windows in the v-berth trunk helps with dissipating heat. The cross flow is nice. We keep the trunk windows closed when using the AC though.
 
That 10 foot fan must really push some breeze. When I was in Med College, our frat house (Houston TX) actually had wooden air plane prop in the attic fan (the study room was in the attic. As I recollect it was about 8 feet in diameter, and had about a 4 hp electric motor.

I agree with the windows--and keeping the hatch open, using a fan blowing thru the hatch.
 
Steve Et. Al.:

I just ordered the Reflectix, but have a question: what is a patten? Specifically, how do you hold the sheets in place?

Thanks,

Rich
 
Rich,
The smaller pieces against the forward windows are covered by the fabric window covering. They are stiff enough to remain in place without assistance. The side windows have 3 wood battens on each side, to aid in holding them in place. The stuff in the berthing area is held in place with velcro tape in several locations. The piece on the underside of the forward hatch fits snug enough, there are no battens holding it in place.
Steve Baum
Homeport of Portsmouth, VA
OSPREY (Ex Mister Sea) 2000 22 C-Dory 2010 - Sold 3/19
OSPREY (Ex ADITI) 2007 26 Cape Cruiser 2018
 
We made a brown paper pattern. This way the Reflectix fits into the side window tracks. Our curtains come over the bottom of the window. Held in place with snaps & magnets.
 
We put on a 9200 Colman Ac and it works very well It actually was. A pretty straight forward install Cut a 14by14 in square The roof was strong enough it was 7/8 in balsa cored with Fiberglass on both sides then added a number 10 ga. marine wire to a 30 amp breaker
I should have done this 10 years ago BTW the Coleman only is 8 in high I looked at the Dometic (same one in my RV)but Coleman seemed the best for us Jim
 
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