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.