Help with Refrigeration Decisions . . .

[CarlF]

I'm also like my keel cooler a lot. While I don't have experience with Engels to compare, my unit uses substantially fewer amps than systems I've had on other boats. The smart controller also seems to help a lot.

One of the pleasant surprises of the keel cooler is no fan or pump noise. I can't hear when the unit is running. I have to open the fridge and listen for the fluid flow in the plates.

Your thoughts on box insulating are good. Definitely plug the drain hole. Get rid of every tiny air leak. As I'm sure you know, air leaks are much worse than thin insulation

Make sure the chosen insulation doesn't absorb moisture. Normal boat humidity will make many forms of insulation almost worthless.

Consider the insulation from Aspen Aerogels that are just appearing. This is flexible (blanket like), doesn't absorb moisture, and is about R10. Installation is easy. You cut it with scissors. It's expensive but less than vacuum panels and isn't subject to leaks.

Carl

[David_Old_Jersey]

Originally Posted by Beersmith

I will be living aboard in Florida and cruising in the tropics, so extra heat is an issue.

My cabin layout:

Have been in the same quandry - and still not resolved to the point of buying anything

Your layout similar to mine (no surprise!), except a bit more galley space.

The "answer" I have come up with is an Engel - large as I can get away with.

The idea being that as it is designed to be moveable that I use that ability -with it's location varying according to boat use. Won't be a 5 minute job (mainly shifting stuff ), more about "on passage" vs in harbour / anchor.

The spots I have an eye on are the 1/4 berth, head of table on floor (actually I am redesiging the table arrangement - presently opposite bulkhead to yours, turning that bunk into a double would be nice so maybe will end up with L shaped dinnette, with the Engel as a seat. Also the Aft cabin and forepeak could be available.......or simply sitting at the head of one of the saloon bunks, and at night time moved to the floor. Me is only looking at 1 or max 2 onboard.......so as long as anything I do can be undone by the next owner should not impact of her value greatly.

me being in a temperate climate means heat not such an issue, but nonetheless a consideration.

I also figure that if no good Engel will be an easy Ebay sell or a tuck away for a future boat etc......plus I will have a benchmark (my own) to compare against any later install with a keel cooler or not.

[Cheechako]

The Isotherm and Frigo units seems to have very good reports. (the ones with no circulating pump and thru hull cooler) The unit that runs only at variable desired speed rather than switching on and off a lot, apparantly burns a lot less electricity. (isotherm?) I think converting from 3" insulation to 4" is more trouble than it's worth. A recent article I read said doors are the worst offender. Lay a dollar bill in the door and shut it, if you can pull it out easily you need to redo the door seal. I have tried various insulation schemes over the years including the vacuum panels. I really didnt see a big difference with any. You still need to charge an hour to 1.5 hours each day unless you have solar and or wind.

[Beersmith]

Originally Posted by Dustymc

Have you looked at the Engel drop-ins?

Engel MB40-DH Drop-In Fridge-Freezer(attached compressor)

I've got one in the mail - hopefully I'll actually know something about them in a week or so.

Those are a good solution, but my problem with the other Engel units are the small internal space. The drop in units are even smaller than the other one I was looking at.

[Beersmith]

Originally Posted by Cheechako

I think converting from 3" insulation to 4" is more trouble than it's worth.

Thanks for that. That is essentially what I am debating right now in terms of a major icebox overhaul.

[Beersmith]

Originally Posted by sarafina

move the sink to port and use a corner model to free up space under the counter for the engels. Would they fit there if the sink wasn't taking up space?

one of the features of this boat that I found ideal was the sink placed near the centerline, so it would drain at all angles of heel. I don't want to loose that.

Good idea, however.

[nwdiver]

I have looked at putting the freezer and evaporator under the end of a settee that backs onto my icebox in the galley, then the refrigerator portion in the galley accessed through the counter (where it presently is) The freezer and evaporator is not accessed very often, sometimes not every day. The unit would spill over into the larger well insulated refrigerator which is accessed many times a day. Thus the freezer would be separate and not exposed every time the refrigerator was opened. You would have to move your sinks to your aft counter where ice box presently resides.

[lasketella]

I have an Engel and LOVE it! I have the SB70 and sacrificed one of the 6 settee seats (one farthest aft starboard (galley) side). We also had to sacrifice the small locker behind the seatback of that settee seat, but definately worth it! This particular model sits quite nicely in it's place. I would consider my settee to be of average size for a 30' monohull. (Bristol 29.9).

Living aboard you will soon realize what needs refrigeration, and what does not. You would be surprised. Therefore you will also be surprised with how little refrigerator space you truly need. At 60 cubic qts, it sufficed 2 adults for 6 months of cruising. The SB70 has a small freezer cubby that does get cold enough for making ice cubes.

The noise level of the compressor is negligible. It runs approx 60% of the time (thermostatically controlled) drawing 2.5 Amps Max (24hrs x .60 = 14.4 hrs x 2.5A = 36Ah/day.

You do lose space by installing this unit, but you can convert your icebox into a dry food storage bin which almost makes up for it.

Here's a picture of the install in progress. This was before we put up the frame (cabinetry) around it. The install was overall very easy.

[Cheechako]

Wow, didnt know engel made a front opener like that. I thought they were all Cooler types. Yeah, I'm hearing as low as 35-40 AH per day with the variable speed/constant run thru hull cooled units also. (isotherm?) It's good to see some improvements in efficiency are finally being made in boat refrigeration. I wonder if Engel is using variable speed compressors also?
And you're right, a huge amount of cold space is not necessary for a lot of cruising. Sure on a big boat with a vast solar array, gen etc you can have a huge freezer, but if you like life simple, a couple cubic feet does it. Most boat systems have too variable temperature throughout the box to keep food long anyway; some things freeze that shouldnt and some are too warm!

[lasketella]

The Compressor on the SB70 is a swing type compressor. Don't quote me on what I'm about to say as I am not entirely certain this is exactly the truth.... BUT:

The compressor is made of a single cylinder with a floating piston that utilizes both the down and up stroke to make compression.

The way I understand it is that the compressor manufacturer (some company in japan) has a patent on this swing compressor technology they created and has teamed exclusively with Engel for use only in their products.

This info is solely based on my research done about 18 months ago so I could be a little off here. Someone correct me (or elaborate) please if I am wrong.

As far as uniformity within the fridge, everything stays just right! The cold stuff stays cold, and the frozen stuff stays frozen.

The compressor is air cooled. You can see the small compressor in my photo above. We just left that part uncovered and it was always adequately cooled even in the tropics.

I purchased the unit online from Engel's website (engel-usa.com) for $649.99 and it came with free shipping! The unit arrived at my doorstep within a couple weeks. Add about $50-100 additional for wires, mounts, and enclosures of your own creativity (not included from Engel) and for less than $750, you have a nice, reliable, and EFFICIENT system!

I've turned a lot of cruisers on to this fridge. I should get some kickbacks from Engel!

[Cheechako]

isnt the heat a bummer in the tropics?

[lasketella]

Oh, and I'll add that my solar array was 200W and I had a house bank of 225AH and I was always seeing >12v day or night. I would not recommend having this fridge with less, but we did fine with that amount of Solar and house bank.

[sailorchic34]

Being Blonde I'm somewhat unconventional. I in my blondness went with a standard 120V fridge with an inverter, which everyone said would not work on the hook. Now being an engineer I know that a btu is a btu weather 12V or 120V. In other words the amount of heat rejection for a size box is the same weather the compressor runs at 12V, 120V, 240V or 4160V

So being Blonde and unconventional, I put a 3.5CF dorm fridge with a small freezer on my boat, bolted it down and put a latch on the door to hold it close when healed. Think it cost me $120 for the fridge and $40 ish for the 700 watt inverter. this was four years ago.

Now when running the fridge pulls 1.4 amps at 120V or 168 watts. Now wait before you say she does not know what shes talking about and oh lordy that's a lot of watts, let me continue.

Factoring in the efficiency of the inverter, I figure its costing me 10 percent more so call it 184 watts. yikes! Big load and it is. The trick is it runs about 2 minutes every 15 minutes in 75-80 degree weather, or .13 hours per hour. I'll round it up to .15 hours per hour as its not exactly two minutes

So take the 184 watts x .15 = 27.6 watts per hour or about 2.3 amps per hour or say roughly 60 amps a day. With door openings its probably more like 80 amps a day. Which is in the ballpark of the typical AB 12V system uses. The difference is the 12V compressor just runs longer..

Ok maybe its just the blonde way of doing things and your mileage may differ. but I just put that out there FYI.

[stillbuilding]

Originally Posted by sailorchic34

Being Blonde I'm somewhat unconventional. I in my blondness went with a standard 120V fridge with an inverter, which everyone said would not work on the hook. Now being an engineer I know that a btu is a btu weather 12V or 120V. In other words the amount of heat rejection for a size box is the same weather the compressor runs at 12V, 120V, 240V or 4160V

So being Blonde and unconventional, I put a 3.5CF dorm fridge with a small freezer on my boat, bolted it down and put a latch on the door to hold it close when healed. Think it cost me $120 for the fridge and $40 ish for the 700 watt inverter. this was four years ago.

Now when running the fridge pulls 1.4 amps at 120V or 168 watts. Now wait before you say she does not know what shes talking about and oh lordy that's a lot of watts, let me continue.

Factoring in the efficiency of the inverter, I figure its costing me 10 percent more so call it 184 watts. yikes! Big load and it is. The trick is it runs about 2 minutes every 15 minutes in 75-80 degree weather, or .13 hours per hour. I'll round it up to .15 hours per hour as its not exactly two minutes

So take the 184 watts x .15 = 27.6 watts per hour or about 2.3 amps per hour or say roughly 60 amps a day. With door openings its probably more like 80 amps a day. Which is in the ballpark of the typical AB 12V system uses. The difference is the 12V compressor just runs longer..

Ok maybe its just the blonde way of doing things and your mileage may differ. but I just put that out there FYI.

Well, may not suit every boat but this is exactly what a lot of bigger production boats are doing. I will follow suit and just use my electrical system to run it - was designed to do this.

[Beersmith]

Originally Posted by sailorchic34

Being Blonde I'm somewhat unconventional. I in my blondness went with a standard 120V fridge with an inverter, which everyone said would not work on the hook. Now being an engineer I know that a btu is a btu weather 12V or 120V. In other words the amount of heat rejection for a size box is the same weather the compressor runs at 12V, 120V, 240V or 4160V

So being Blonde and unconventional, I put a 3.5CF dorm fridge with a small freezer on my boat, bolted it down and put a latch on the door to hold it close when healed. Think it cost me $120 for the fridge and $40 ish for the 700 watt inverter. this was four years ago.

Now when running the fridge pulls 1.4 amps at 120V or 168 watts. Now wait before you say she does not know what shes talking about and oh lordy that's a lot of watts, let me continue.

Factoring in the efficiency of the inverter, I figure its costing me 10 percent more so call it 184 watts. yikes! Big load and it is. The trick is it runs about 2 minutes every 15 minutes in 75-80 degree weather, or .13 hours per hour. I'll round it up to .15 hours per hour as its not exactly two minutes

So take the 184 watts x .15 = 27.6 watts per hour or about 2.3 amps per hour or say roughly 60 amps a day. With door openings its probably more like 80 amps a day. Which is in the ballpark of the typical AB 12V system uses. The difference is the 12V compressor just runs longer..

Ok maybe its just the blonde way of doing things and your mileage may differ. but I just put that out there FYI.

this is very interesting. Thanks for the post! given me something to think about