refer in the tropics, which type system do you have

[Cpt Mark]

Hi All,

I'm still researching which system to put into my boat. Spoke with a marine provider company who sells many different brands/types of refer/freezer systems.

Interestingly enough I was told in the tropics I'd need water cooled, period. Not at all what I'm reading here so far. We discussed some of the negatives of water cooled in the tropics including organisms that grow in the system and the need to kill them and flush periodically.

S
Keel cooler is a nonstarter for me. I have a cat and the ability to beach it. Pump driven water cooled I'm already set up for but if I can cut that part of the system out to reduce the amount of things that can go wrong am more than happy to do so.

So here's my questions for those who are or have been ACTIVELY cruising in tropical environments. 90f+ air temp, 85f+ water.

1. Air cooled or water cooled?

2. Do you use a holding plate system or an evaporator plate system?

3. Separate refer/freezer box's or spill over?

4. Does it meet your needs? ie- is frozen stuff frozen. Can you freeze that huge fish you just caught?

Please add any other comments you feel relevant.

Thanks,

[OzePete]

What you are told is mostly correct although you don't have to have hull penetration to achieve the water cooling benefits.
Some here will say you don't need water cooling for cruising the tropics, (mostly those that don't make or sell both!!) and that is correct too, and in many cases air cooling is adequate except that water cooling in extreme conditions works far better.

We manufacture both types, air only and air / water, but always recommend our air and water cooled system for tropical use, very large cabinets or if ventilation is a problem.
But our air / water cooled system is quite unique.. It operates as an air cooled unit unit and only if additional condenser cooling is needed does the water cooling assist. This is thermostatically controlled and switches on / off a micro pump that re-cycles fresh water through a separate pipe run in the condenser as needed. Most times it is not but when it is, its a winner. (Model AW480)

There are many benefits to this method the most important being that no water has direct contact with the refrigerant galleries. The water cools the condenser fins which in turn cool the refrigerant so no electrical corrosion (electrolysis!)

The AW480 can operate as either air cooled only, water cooled only or the preferred air AND water cooled.

Next the condenser temperature is maintained within engineered parameters so no more over or under condensing which badly effects the performance of all types of systems.

Finally lower power consumption:
A compressors consumption is related to the pressure it pumps. (High side pressure) The higher the pressure the harder it pumps and the more battery power it consumes.
For example an air cooled condenser in 35C ambient will operate at 45+C or approx a 155+ PSIG head pressure. In the same environment an air / water cooled system will operate much easier with an approx high side of 135 PSIG. And the PSIG difference expands rapidly as the ambient climbs!

Cheers OzePete

[OzePete]

Sorry Mark,
Regarding your other questions:

1. Air cooled or water cooled?
A: Air and water cooled.. See AW480.

2. Do you use a holding plate system or an evaporator plate system?
A: Eutectic plate(s) for far greater efficiency.

3. Separate refer/freezer box's or spill over?
A: Depends on compartment sizes, insulation, are they adjacent each other etc etc. Many questions and as always we strongly suggest getting a 'Heat Load and Duty cycle estimate done so you can purchase adequate equipment. We can do a no obligation estimate for you.

4. Does it meet your needs? ie- is frozen stuff frozen. Can you freeze that huge fish you just caught?
A: Absolutely. A freezer must hold things frozen albeit while keeping most things frozen is easy, bread and ice-cream are difficult and power consuming.

As for the huge fish can I take the liberty of dropping the 'huge' (surely a fisherman's term!) and say yes!

Cheers OzePete

[Davo1404]

I have been running an Ozefridge since 2007 in tropical Queensland. It has a eutectic tank & is water-cooled. Mine is the older unit where you can control the water on or off. It is definitely more efficient over the summer months with the water on. Also another advantage of this unit is that it uses the vessels fresh water tanks. So know corrosion or barnacles to grow inside the pipes.

[StuM]

Your poll is seriously flawed. I have air cooled separate reefer/freezer boxes but can't select both those two options. which should I tick? My freezer also has an engine driven eutectic plate but that's also not an option.


But as a point of reference, they work fine in here in the tropics.

[s/v Jedi]

I built my own system, water cooled, with evaporator plates, separate systems for fridge and freezer in 2004. It needs replacing now and I will be switching to mobile boxes from Engel and Snomaster.

[Sailor647]

ACTIVELY cruising in the Sea of Cortez Mexico for the past 5 years. Tropical environments - yes. 90f+ air temp (100 in the summer), 85f+ water (75 water temp in the winter months)

1. Air cooled or water cooled?
A: Keel cooled. Frigoboat. The air temperature where our compressors are located (in a huge aft lazarette) gets HOT. Hotter than the sea temperature.

2. Do you use a holding plate system or an evaporator plate system?
A: Evaporator plates. Two seperate compressors (sized to work with cubic feet size of boxes), two evaporators - two completely seperate systems. (Redundancy/backup)

3. Separate refer/freezer box's or spill over?
A: Seperate boxes, but there is a 1" drain hole from the 5 cubic foot freezer to the 7 cubic foot fridge in the seperating wall. The fridge has a drain/pump for removing the water after freezer defrosts, which we do monthly.

4. Does it meet your needs? ie- is frozen stuff frozen. Can you freeze that huge fish you just caught?
A: Completely meets our needs! We make 4 trays of ice daily for cocktails and the freezer is cold and big enough to store whole dorado, tuna, sierra we catch underway until we can clean them. We can keep ice cream frozen.

Please add any other comments you feel relevant.
A: Our 12v Danfoss compressors are super efficient. We can stay out indefinetly using only solar to recharge the house batteries (8, AGM 105 amp hour). Not a single problem with the keel coolers or compressors since install. We did get a circuit board wet once, which we had to replace. (They are not waterproofed as stated in the literature.)

The best addition to the refrigeration system by FAR was installing digital Carel thermostats, one for each compressor (fridge and freezer). The manual thermostats wern't sensitive enough and caused the compressors to run practically non-stop. Plus, it's comforting to just glance up and know the inside temp of the fridge and freezer.

The fridge is top and front loading, and the freezer is top loading. The boxes are original to the boat (30 years old) and must be hella-insulated - which makes a huge difference in your overal refrigeration success or failure. If the boxes are wimpy, you'll have a hard time keeping things cold in the tropics - well, unless you have a genset that you can run 24/7.

[iseadreamer]

Twenty years 6 months cruising western Mexico.
Isotherm cold plate in 8 cu' box freshwater cooled with main water tank of three. Solar only adequate at anchor. Foods frozen/cooled like normal.

SV Seadream

[Cpt Mark]

Originally Posted by StuM

Your poll is seriously flawed. I have air cooled separate reefer/freezer boxes but can't select both those two options. which should I tick? My freezer also has an engine driven eutectic plate but that's also not an option.


But as a point of reference, they work fine in here in the tropics.

Yes my poll absolutely sucks and I couldn't figure out how to add more questions or delete it after I posted. Very sorry about that. Please disregard the poll unless someone can tell me how to fix it.

Thank you for your responses though.

[Cpt Mark]

Originally Posted by s/v Jedi

I built my own system, water cooled, with evaporator plates, separate systems for fridge and freezer in 2004. It needs replacing now and I will be switching to mobile boxes from Engel and Snomaster.

I bought the biggest Snomaster available. Works as advertised. However, I only have room for one which turned a 9 cf freezer/refer into a 3.5 cf unit. Not good. The latch mechanism requires the box to sit proud so I lost that workspace on top of a limited space galley. It was an experiment and now I'm going back to separate boxes.

Take a good long look at where you will be installing these things. Snomaster has the better warranty and better seals which is why I chose them. Even became a dealer lol.

Snowmaster is in Portland OR if you're interested pm me.

[Minggat]

I agree with StuM. Flawed survey.

Stand alone Fridgefreeze. Draws 12 amp hrs during the night. 13 when weather is hot.

I so wish had figured out sooner what works best for me. Refrigeration is such a non-issue anymore. Very expensive lesson learned.

My built in box is still fully functional. Used only for dry storage since 2008.

[Cpt Mark]

Originally Posted by iseadreamer

Twenty years 6 months cruising western Mexico.
Isotherm cold plate in 8 cu' box freshwater cooled with main water tank of three. Solar only adequate at anchor. Foods frozen/cooled like normal.

SV Seadream

I'm curious why solar is only adequate at anchor? Do you mean it's barely enough or that when underway for some reason it is not enough?

[SteveSadler]

Our freezer is keel cooled, (no water in system) fridge air cooled. The freezer is silent draws less then the fridge, who's fan is so noisy we shut it off at night. I'd love to find a way to divert all that hot air out of the cabin, maybe into the aft head to use as a drying room? Every year I threaten to replace it with a keel cooled unit, but then if it ain't broke why fix it?

[blubaju]

Isotherm holding plate w Danfos bd80 (!!), water-cooled, spillover. 2010 it came with a far to strong waterpump, the to high backpressure killing the pump membranes. Another brand makes a pump that fits exactly, size & power and runs 8 years now. Freezing the big game fish it might still be to small, but you did not mention the size of your yacht & power supply

[Simi 60]

Originally Posted by Minggat

I agree with StuM. Flawed survey.

Stand alone Fridgefreeze. Draws 12 amp hrs during the night. 13 when weather is hot.

I so wish had figured out sooner what works best for me. Refrigeration is such a non-issue anymore. Very expensive lesson learned.

My built in box is still fully functional. Used only for dry storage since 2008.

As in an off the shelf house type?