Ice Box Refrigeration Conversion Engle?

[mischief]

Okay when talking about built in refridgeration conversion kits there's always lots of talk about the BD-35 compressor systems like isotherm Novakool etc. but when you talk about portable fridges Engle always seems to be the better pick.

So how come nobody puts in the engle conversion kits into their ice boxes?

I know what the naysayers have to say about swing compressors but again when it comes to the portables why is engle seem to be the most picked for being efficient and reliable?

Seems to me I should consider one for my upcoming conversion. Too bad I've never heard anyone putting one in?

Cheers

[danhaun]

I put an Engle drop-in unit (MB-40) just three weeks ago. It was an easy install with the remote compressor that I mounted 4 ft away from the box. It cools to 40F on the "1" setting (of 5 possible). I am on the Gulf coast now and it reaches 93F every day with heat index above 100F. I calculate about 40% run time. The box is small though and I do not know how it would work with a large box. I measured the temp of the outer box surface and find just 2F over ambient so I judge the factory insulation to be adequate and did not add any.

So far I am pleased but this is hardly an endorsement based on such a short time. If you check out the blog at | | you will find that they have also just installed a conversion model.


Good luck with the project.

Dan

[danhaun]

The link I gave didn't show properly but still works. Also, I meant 2 degrees below ambient (not above) and add that I am on the Gulf coast of the USA.

[Richard Kollmann]

When it comes to a refrigerated box of 2 1/2 cubic feet or less Engel's portables are a good choice because there is a completely balanced energy efficient unit for a small Cooler, Refrigerator or a very good freezer depending where thermostat is set.

If a Swing compressor ice box conversion system like Norcold or Engel is installed in a 4 cubic ft ice box in a warm climate it then becomes only a drink cooler.

[mischief]

My ice box is about 70l or so. So not much over 2cu. I see engle offers their portable fridges up to 80l or so.
Are these larger ones not as good?

I would like a
Small freezer section, since my box is small and the way it's laid out means I'm limited. A spill over system would mean a deep skinny freezer.
So I was thinking of using a small "0" evaporator.

The nova Kool are all too large but the smallest of the isotherm will fit quite well. I had planned too insulate between the bottom of the "o" to be able to have a colder freezer section.

The "o" is rated max fridge 125l freezer 40l its L 210mm x W 240mm x H 95mm
The system runs a BD -35 compressor and has the quick connects plus to fit my compressor in a suitable location I'd have to add the extension lines.

I'd rather not have any quick connects but I have been asking around and I can't seem to find anyone that can build a system every fridge mechanic I've spoken with about 10 so far they don't know anything about boat Refridgeration and all the marine shops just refer me to the kits.

So I wouldn't even know where to get the components in Australia to build my own system. Plus I'm so limited on time I thought the drop in kits would suffice. But would it be a balanced system? I have no idea.
If I get to pressed for time I was thinking of just putting it in the factory poorly insulated box and then in a year or so rebuilding the box. And reinstalling the evaporator maybe I could put solid lines in at that time?

[gspeak]

Have you had a look at the Ozefridges? I converted my engine driven system to one of these. Has been going non-stop for 18 months now. Brilliant.

They are based in Victoria & their service is first class & pricing is great.

Ozefridge

I posted photos of my install in another thread. See here

Dave

Originally Posted by mischief

My ice box is about 70l or so. So not much over 2cu. I see engle offers their portable fridges up to 80l or so.
Are these larger ones not as good?

I would like a
Small freezer section, since my box is small and the way it's laid out means I'm limited. A spill over system would mean a deep skinny freezer.
So I was thinking of using a small "0" evaporator.

The nova Kool are all too large but the smallest of the isotherm will fit quite well. I had planned too insulate between the bottom of the "o" to be able to have a colder freezer section.

The "o" is rated max fridge 125l freezer 40l its L 210mm x W 240mm x H 95mm
The system runs a BD -35 compressor and has the quick connects plus to fit my compressor in a suitable location I'd have to add the extension lines.

I'd rather not have any quick connects but I have been asking around and I can't seem to find anyone that can build a system every fridge mechanic I've spoken with about 10 so far they don't know anything about boat Refridgeration and all the marine shops just refer me to the kits.

So I wouldn't even know where to get the components in Australia to build my own system. Plus I'm so limited on time I thought the drop in kits would suffice. But would it be a balanced system? I have no idea.
If I get to pressed for time I was thinking of just putting it in the factory poorly insulated box and then in a year or so rebuilding the box. And reinstalling the evaporator maybe I could put solid lines in at that time?

[Richard Kollmann]

mischief , Selecting a 12/24 volt refrigeration unit is a difficult task for either a box smaller than 3 cu ft or one that is larger than 6 cu ft. After box size is determined it is easy to determine compressor and evaporator size. If your box’s actual size is 3 cu ft then its worst case daily evaporator heat removal required at +12 F is 1800 Btu daily. I define tropical climate temperatures to be 90 degree F seawater and 95 degree F air temperature. Either the BD35 compressor at its lowest speed or Engel or Norcold swing compressors at their fixed speed will consume about the same amount of heat while running 13.8 hours a day. Using compressor manufacturer data either Danfoss BD 35 or the Swing compressors are adequate for this size box to consider a larger compressor like a BD50 or EB/BD80 is a mistake.

In the real world mischief’s boat may never see heavy use in a severe tropical climate. To adjust daily btu consumption to a milder climate reduce Btu by 2% for each degree F of cooler seawater. Example seawater is 20 degrees F cooler then than tropical Daily Btu is then 1080 Btu and compressor will run only 8.3 hours per day consuming around 24 amp-hrs per day.

mischief, I would not want these very small line connections soldered unless it is done in a controlled environment. There is nothing wrong with well designed refrigerant line connecters that rely on final permanent metal to metal seals Engel and Norcold and several others use leak proof connecters. Frigoboat and E Z Kold are the exception.

[mischief]

Hi Richard and thank you for your detailed post. I have read many if your writings and realize you know what you speak of.
I'm slightly confused about the connects an wonder then if the quick connects that isotherm uses are okay and reliable? If also I use them and connect with my old ice box and than later rebuild them, thus disconnecting and reconnecting is that okay or would you loose too much gas?

Finally for such a small I've box and what you have said I gather neither a swing or BD 35 has an advantage over the other?

Kind regards

[Richard Kollmann]

Isotherm as far as I know is still using metal to metal permanent seal line connecters that retain refrigerant when disconnected. You should know that these connecters may leak when disconnected. Adler Barbour I think was the only one that tried to comply with the clean air act in 1996 by using self fracturing one time metal to metal line connecters.

When comparing almost equal performance between icebox conversion units Swing compressors and Danfoss BD 35 compressors:

Danfoss compressor system is more expensive.
Maintenance costs are less on Danfoss because electronics are not repairable locally.
Danfoss, Less days out of service for electrical repairs.
Location of condensing unit is important on both systems so fan cooling evaporator heat disposal is important in warm climates.

In the right installation application both style units could operate for the life of boat and yes even without repaits.

[mischief]

Thank you.

Does the above mentioned "o" evaporator sound like a good size for my size box? Current insulation is as noted and I hope to redo my boxes using about 60mm of cryogel which should yield about 25r. When I redo my box I also may end up with an extra 10-15l depending on how it goes.
I know its all theoretical at the moment and I have not given absolute measurements. But am I roughly on the right track if I pick the isotherm with the smallest O evaporator mentioned?
What is the ideal balanced Refridgeration consist of?
Thanks

[Rhapsody-NS27]

I have an Adler Barbour Coldmachine installed by a previous owner that works great. I put bottles of water in to get cold then ended up with blocks of ice. Down side would be if I was traveling and not on shore power because of power draw. My unit's label says it will draw as much as 5 amps. The power draw is a big consideration for cruisers who may not have access to shore hook ups. That, I think, is why some people will consider one system over another. Compare power requirements, and that may help your decision too. I've heard the Engle portable units are lighter than others on power consumption.

[RaymondR]

One of the problems I experienced with the kit type installations was that they appear to use very thin walled tube in the evaporators and I lost gas twice in two years because of pin holes corroding in them.

I have never owned an Engel but have had both the BD35 and BD50 from Danfoss. I cut the top of the BD35 to see how well it was built and was very impressed with it's construction.

I am at present rebuilding my built in fridge as a eutectic system with a water cooled condenser. I found with my old system with an air circulated evaporator that by placing about 80mm of water in the bottom and allowing it to freeze I could get about 4 days hold over without running the compressor. I then put a seven day timer on it so that it did not start running until about 0900 and shut down about 1530. In this manner the compressor only ran during the day when their was plenty of power available from the solar panels and did not pull the batteries down during the night.

Although I did not like the quick connecter because they are a potential leakage path in practice I found that the leaks happened elsewhere. If I was to buy another kit I would probably install it with the quick connectors and if the system required regassing because they had leaked remove them before regassing it.

After about 12 years of mucking about with boat refrigeration, the initial build, one rebuild and now a second I tend to feel knowledgeable enough to offer advice on the subject.

If you are going to cruise in the tropics use a water cooled condenser for no other reason but to keep the heat out of the boat. It should also condense better and allow the system to run with less head pressure and draw less amps.

Also you should put a computer cooling fan under the compressor if you can, mine tended to run very hot in the tropics.

I have found 4" of polyurethane foam sufficient but if building another box from it would cut, preglass and sand the panels on the faces going inside before putting it together as it's a bugger of a job once you turn it into a box.

I am in Darwin and ordered a pump from Ozefridge and received it within four days of placing the order which is pretty good service.

I like the look of the Ozefridge units, particularly the eutectic systems and compressor/WC condenser/control units and this is what I would buy if I wanted another kit system. I would discuss the installation of a 7 day programmable timer if they don't already have one in their control system and I would see if they have an alternative eutectic fluid, maybe alcohol/water, rather than glycol/water.

I would also purchase a copy of Nigel Calders, Refrigeration for Pleasure Boats. It's a bit dated and more oriented towards engine driven eutectic systems but still good value for money if you want to understand boat refrigeration.

[mischief]

Okay I missed Raymond's post before I posted below. So Ill address that first.
The I fridge system sounds like the Isotherm intelligent control system or whatever they call it. It uses a small eutectic plate.
One issue I suspect is that with more computer control and advanced features there it is a more complicated system. Therefore more things to potentially go wrong and more complicated and expensive to repair.

I'm not totally against a small type eutectic system and I plan to utilize my freezer section in the O as a semi holding plate filled with frozen goodies and a small insulated barrier so that the freezer section draws down a lot colder before it shuts off the compressor.

Anyway now my post that I wrote before........



Ahhhrrgggggg I just did a longish post but it didn't go through.

Oh well probably better for everyone else anyway, I'll just get to the point.

Energy consumption, reliability, ease of maintenance and repair along with availability and a modest price are ll important.

At the moment I'm looking at the isotherm kit with the smallest O condenser as that's the only condenser that appears to fit into my box the best and will give me a small freezer section.
Unless anyone can point out another kit that would be better that is in the same price range and available in Australia ill probably get one soon.

Cheers

[gspeak]

So have you looked at the Australian made Ozefridge or not. You seem to be ignoring it. Or doesn't it fit your plans. All I can say is that our very large fridge run with the Ozefridge eutetic unit uses way less power than the small portable Engel we use as a part time freezer. They have systems for split freezer as well.

That is up here in the tropics of North Queensland.

Dave

[mischief]

Okay I'll definitely check out ozfridge to make a more informed decision.

To be honest I was kind of ignoring them. Guess I'm assuming they will be priced high, we shall see.....