Who provides the best 12 volt refrigeration systems?

[Typhoon]

Originally Posted by Richard Kollmann

All three of the Cold Eh, CoolBlue and Isotherm units are repairable by most mechanics and DIY boaters. If Isotherm is your choice you would need to know how to remove the ASU module and be able to rewire Danfoss module to operate unit without ASU if it were to fail. Also the through hull condenser is so equipped will require regular cleaning and zinc maintenance.

Before selecting a icebox conversion unit manufacturer I would point out a 47 foot boat's large box generally requires a large refrigeration unit. The climate where you plan to cruise in, The temperatures in box you want to maintain and the boats electrical power grid capacity are the first things that need to be evaluated.

We only use Danfoss and Parker components in our systems. High and low pressure access valves and two sight glasses to insure a correct charge and for a quick check of the systems health. If ever need be, the system is very serviceable by just about any service technician. Also Danfoss and Parker components are stocked on shelfs all over the world .

Regards John
www,coldeh.com

[sainted]

I have two Sea Frost units, one for the reefer and one for the freezer. They've both worked flawlessly for over 10 years. When you order the kit, you'll work with the very knowledgeable owner, and they will custom make the evaporator to fit your fridge cabinet. Tech support and parts are likewise readily available.

[Richard Kollmann]

Originally Posted by nmccubbin

As I mentioned when starting this thread, the electrical system is an add on to a mechanical one that works well but needs engine running when we have plenty solar/wind power available.

Thus a small unit will suffice. refrig is only 4.4 cu ft and is well insulated (6" plus)

Sorry I over looked the present mechanical system. The problem to complete your alternative power system is finding an evaporator for the 12 volt unit that will fit and be efficient. I assume you would not want a space consuming eutectic plate.
Nova Kool has an excellent complete BD50 compressor system for $900 with a wide selection of evaporators. Solve evaporator problem before selecting a condensing unit.
I also forget SeaFrost custom thin evaporator plates.

[Mithril Bham]

I have a Danfoss that has run since 1978. Had to replace a board a few years ago. Bought a old one for $50 and has run ever since. New unit installed is $1,000. I think it depends a lot on where you are located. I expect it to break down any day but keeps running.

[benzy]

Originally Posted by bushytales

In my opinion, and that of other sailing friends, THE best refrigeration system by far is an Evakool - manufactured on the Sunshine Coast in Qld AUSTRALIA.
My mate installed one in his catamaran and has run it for 17 years...never once switched it off. I have one as well and thankfully it simply does the job.
And importantly they are a phone call away as they manufacture at their factory in Australia..

Just reading about the Evakool. Website says at 35 deg celsius ambient temperature, with the fridge set to +5 deg celsius, it only draws about 1.5 amps. Is what you have experienced? That is amazing if so! Our danfoss draws 6 amps!!!

[Captndave1]

I replaced my old Firgobot with a new Vitrafrigo. Works great, cools better and runs a lot less.

[bushytales]

Originally Posted by benzy

Just reading about the Evakool. Website says at 35 deg celsius ambient temperature, with the fridge set to +5 deg celsius, it only draws about 1.5 amps. Is what you have experienced? That is amazing if so! Our danfoss draws 6 amps!!!

Yes, that is correct. They tested them many times across the Simpson Desert where temps close to 50 degrees C are not uncommon.
Danfoss are certainly thirsty when it comes to power usage.
Cheers

[Mike Banks]

Engel.

Get the one that you can put in your own freezer bin, if they are still supplying them. This model has the cooling coils remote from the compressor and connected by hoses, if you can or do have an existing high-quality thermally efficient large ice box.

Failing that, I used TWO 40 litre freezers by Engel, the ones with the polymer cases. One I used as a refrigerator, the other as a freezer.

Prior to that I had a Danfoss compressor and a cabinet fridge, nothing wrong with it as far as the motor etc was concerned--but every time one opened the door all of the cold air poured out onto the galley floor. A bin type does not spill the denser cold air--so will save energy.

Never had a problem with the Engels. Trouble free and efficient--comparatively silent. Just a gentle hum through which one can sleep.

When in port on marina power. I did use a commercially available small refrigerator, but it too could have been run through an inverter as far as power demands were concerned--except for losing cold air every time the door was opened.

Engel. I never regretted buying them for a moment--and I can use one in the car should I be travelling anywhere.

[hzcruiser]

Originally Posted by benzy

Just reading about the Evakool. Website says at 35 deg celsius ambient temperature, with the fridge set to +5 deg celsius, it only draws about 1.5 amps. Is what you have experienced? That is amazing if so! Our danfoss draws 6 amps!!!

Hello Benzy,


Just to avoid possibly jumping to wrong conclusions: they quote it's drawing 1.5 A, measured over a 24h period. That means, it consumes 1.5 A * 24h = 36 Ah per day. OK.


If your Danfoss-powered fridge has good insulation and you're not opening the door very often you might get a duty cycle of 25% (meaning it's on for 15 minutes per hour on average)? If so, your fridge would consume 6A * 24h * 0.25 = 36 Ah.
Surprised? It's exactly the same consumption, just a matter of presenting the numbers differently. However, if your fridge kicks in and always runs for 30 mins, then stops for 30 mins, it would have a duty cycle of 50% and hence consume 72 Ah per day.

What counts is the overall consumption per day, or week, or year, if you want. The efficiency of different compressors surely varies, but not by a factor or 2 or 3. A lot comes down to the insulation, content of the fridge (full is better than empty), ambient temp and the time the door is open.

As a side note, like a few others on this forum, I tend to cringe a little bit when reading a "power usage of 1.5A/Hr". This should've been corrected by the company (or the editor of their website) a long time ago...

Full disclosure: I'm looking for a replacement fridge/freezer myself at the moment but those details are just a little off-putting, to be honest. Nevertheless, I believe their fridges are up there with the best.

[newhaul]

Originally Posted by hzcruiser

Hello Benzy,


Just to avoid possibly jumping to wrong conclusions: they quote it's drawing 1.5 A, measured over a 24h period. That means, it consumes 1.5 A * 24h = 36 Ah per day. OK.


If your Danfoss-powered fridge has good insulation and you're not opening the door very often you might get a duty cycle of 25% (meaning it's on for 15 minutes per hour on average)? If so, your fridge would consume 6A * 24h * 0.25 = 36 Ah.
Surprised? It's exactly the same consumption, just a matter of presenting the numbers differently. However, if your fridge kicks in and always runs for 30 mins, then stops for 30 mins, it would have a duty cycle of 50% and hence consume 72 Ah per day.

What counts is the overall consumption per day, or week, or year, if you want. The efficiency of different compressors surely varies, but not by a factor or 2 or 3. A lot comes down to the insulation, content of the fridge (full is better than empty), ambient temp and the time the door is open.

As a side note, like a few others on this forum, I tend to cringe a little bit when reading a "power usage of 1.5A/Hr". This should've been corrected by the company (or the editor of their website) a long time ago...

Full disclosure: I'm looking for a replacement fridge/freezer myself at the moment but those details are just a little off-putting, to be honest. Nevertheless, I believe their fridges are up there with the best.

now I would believe the 1.5ah per hour if it were written that way. (1.5ah x24 hrs =36 ah per day)

[hzcruiser]

Originally Posted by newhaul

now I would believe the 1.5ah per hour if it were written that way. (1.5ah x24 hrs =36 ah per day)

Hmmm, not sure about your math here, sorry.


1.5 Ah x 24 h would be 36 A h^2



But yes, 1.5 Ah per hour would be correct, yet the same as just saying it consumes or draws 1.5 A, full stop.

[newhaul]

I agree with several others here on service call the company and see who answers the phone . That will tell you a lot about service. If I call cool blue I know rich will answer if I call cold eh I'm sure john will answer ( possibly his wife) as to oz Pete I'm assuming he would be the one to answer. I'm on the wrong end of the pacific for his systems. ( shipping costs make the system cost prohibitive for me and my customers.

If looking to capitalize on "excess" solar then a holding plate system would be your best option( not the cheapest) and for that I recommend cool blue .

[newhaul]

Originally Posted by hzcruiser

Hmmm, not sure about your math here, sorry.


1.5 Ah x 24 h would be 36 A h^2



But yes, 1.5 Ah per hour would be correct, yet the same as just saying it consumes or draws 1.5 A, full stop.

no its not the same 1.5A is an instantaneous measurement and denotes no timeframe.

[a64pilot]

I don’t believe there is any system as long as it’s components are correctly matched to each other that is really much if any more efficient than any other.
Remember all these claims of efficiency are closed systems at equilibrium, no door is opened no cold beer removed and replaced with hot beer etc.

The secret to efficiency is insulation, and that doesn’t come in an ice box conversion system, you have to supply that.

In real world use, my duty cycle is way up there, probably close to 90%, reason is throw in a case of beer and a 20 lb water melon in the fridge side, and or a few steaks in the freezer side, and it’s going to run all day and night cooling that down.
But if I let it sit without ever opening the door and cooling nothing down, well then I could quote some good consumption numbers.
So for real world use, don’t use those marketing numbers to plan your energy budget, if you do, your going to bust it.

I think you need excess capacity, so that when you put that case of beer or that watermelon in and it’s 90+ degrees, your fridge doesn’t come up to 60f until it cools down, you want it to stay cold, and that takes excess capacity, and or some nice big cold plates that can absorb all that excess heat and not let the box get warm.

[Madehn]

so I am getting ready to change out my system to 12 volt- both Rich and John took the time to answer my questions in depth and detail with no BS. i am proabaly going to go with Rich's solution simply because the two boats next to mine have his system and cannot say enough good things about the systems or the service. In fairness i believe John also has a great reputation for taking care of people and doing the right thing- i dont think you could go wrong with either of them.-- just my two cents