Ozefridge Reviews

[Pelagic]

Anyone have experience with these refrigeration manufactures?
Ozefridge | Multi-voltage Eutectic Refrigeration

[Pelagic]

No one from Australian have tried them?

[Neptune's Gear]

Yes, best unit I've seen. Check out OzeFridge, our experiences using them Boating Gear fit for the King for my experiences. Which is why I now sell them!!
Please let me know if you have any questions.
Matt

[Pelagic]

Thanks Matt,

Just in the preliminary design stages of converting my little used starboard Nav. Station into a built in refrigeration space and am considering using Ozefridge components. They seem like a good product but are little known outside of Australia.

I like their idea of borrowing the Fresh Water in a closed loop to cool off the top of the condenser as a switchable option.

It will be interesting to know how well that water option helps in the Tropics in hot humid tropical 30C conditions where my 19m steel sailboat always lives.

This is my first time building a live aboard cool box so lots of research in progress to find the right balance and supplier

So far:…..I am considering using the Dow blue board R5.2 and as the most important area to combat heat penetrating the cabinets is the *base followed by the walls, and the top being of least importance I am considering 150mm for the base, 100 for the walls and 50mm for the top. (* Heat rises and its easiest way in is up through the base hence the need for greater insulation, wall penetration is at an angle and unless in direct sunlight, little heat will enter downwards through the top. Also I guess thinner tops / lids are easier to access)

The available Refer space is Rectangular and is mounted on a solid 2” plywood/teak floor well away from any hull sides or heat sources.

Allowing additional 15mm for finished bin Liner per 6 sides then my inside bin dimensions would be reduced to: W1100 mm x H870mm x L500mm or about 400 liters of usable storage space

I like the flexible idea of 2 equal but separately chilled cabinets of about 200 liters each that can independently be used as either Fridge or Freezer, or Both.

By keeping them independently serviced with 2 refer system units yet having a removable divider in between, it would allow me to keep both sides cool with just one unit in case of a parts failure.
Anyone designed before for that redundancy?

Lots of unanswered questions about best hatch design, seals and sourcing ABS liner materials, so all advice is welcome

[two fast]

Hi I self installed a freezer unit 3 years ago, and find it fantastic, It is installed as 12v only as I'm at anchor or on the mooring
The unit came well boxed and with clear instructions before I purchased I visited the factory which was spotless
I run it though a 160l or 40gallon fresh water tank which doesn't get even warm I also have a fan sucking warm air out I would highly recommend them, hope this helps


Sent from my iPad using Cruisers Sailing Forum

[downunder]

Some discussion on the Ozefridge in a couple of recent threads.

http://www.cruisersforum.com/forums/...-134547-3.html

http://www.cruisersforum.com/forums/...ns-119534.html

They have a excellent reputation.

[two fast]

I hope the 2 photos attached work!


Sent from my iPad using Cruisers Sailing Forum

[Neptune's Gear]

I think there is a bit of confusion here. If you use the Ozefridge AW480 with the water cooling, it will be Water Cooled - the fan will only cool the electronics, and the water will cool the refrigerant. If you turn off the water cooling, the unit will be air cooled only, and you will feel the warmer air coming out from the fans.

Just to re-iterate - these units are fresh water cooled - no thru hull, no anodes etc. My own unit cools a 270 ltr freezer (to -15 to -21 deg C) AND a 270 Ltr Fridge to about +4. With the one unit. There is a heat exchanger system that transfers cold from the freezer to the fridge, and that is controlled by a thermostat. It has smart power mangement, will auto swap to shore power if available, will turn on when the batts are charging etc - uses power when it is abundant.

Our system has been in continuous use since 2010. It has had one cooling fan replaced (PC type fans). It is by far the most efficient I have seen, and ran our setup on the equator, operating about 30% of the time. The unit draws under 6 amps, so that is 36 amp hours per day, to provide 270 ltrs of freezer AND 270 Ltrs of fridge cooling, on the equator! We have never noticed ANY extra heat in the water tank, or in the boat interior. That is why I now re-sell the units here in NZ.
I know some of you want to disagree, and think your systems are better, but that is my experience of these systems. I have not seen any units that provide this much cooling for this little power consumption. Of course I have not seen everything out there, (but most, I think) but until I do see something better, this is the one!
I've just re-done my website, and have not yet put the cabinet design info on it, but in the meantime, it's on Ozefridge's site.
Cheers
Matt

[Pelagic]

Originally Posted by Neptune's Gear

I think there is a bit of confusion here. If you use the Ozefridge AW480 with the water cooling, it will be Water Cooled - the fan will only cool the electronics, and the water will cool the refrigerant. If you turn off the water cooling, the unit will be air cooled only, and you will feel the warmer air coming out from the fans.

Thanks all for the extra links to Ozefridge discussions and the photos…. Seems like the OzeFridge is well received in Australia.

Matt, I’m a bit confused about your above statement?

My understanding is that by installing the AW480 you do have the “option” of water or air cooling and that it is switchable depending on the heat load or if you want to turn off the water pump at night…. Then if it cycles on the twin fans will kick into high gear if needed?

Their explanation is on this page: Why Ozefridge | Ozefridge

Am I missing something??


The A480 uses a triple pass air only condenser while the AW480 model uses the unique Ozefridge engineered air and water cooled condenser and can operate as either air or water cooled.

The condenser fan and water pump are thermostatically controlled to maintain correct condensing. On both models, the condenser temperature can be read by pressing the lower left controller button. Condenser fan and pump are thermostatically controlled to cope with all environments.

AW480 with water cooling: Heat laden refrigerant gas flows through the ‘yellow & purple’ coil passes while water is sent separately through the ‘green’ coil passes to extract heat.
This condenser allows the system to be operated as ‘air cooled only’ with heat dissipated via the condensers massive 6550 square cm of fin surface area.
When water cooling is employed, water passes through the water coil cooling the condensers fins and this in turn cools the refrigerant gases.
This simple but practical method of water cooling eliminates electrolysis problems associated with other methods such as ‘keel coolers’ and ‘shell and tube’.
Unlike other water cooled condensers, the refrigerant is not in direct contact with the water galleries and therefore can’t be lost or contaminated due to electrolysis or corrosion.
This condenser is best water cooled by re-cycling water from the vessel’s fresh water tank with the pump kit supplied. ( Using raw water is not recommended and will cause harm eventually)
The Ozefridge condenser is conformal coated to resist air borne corrosives.
Water cooling is essential on twin plate freezer systems and highly recommended for all systems specially if used in the tropics or other hot climates.
Water is provided by using the Ozefridge P3 water pump kit supplied with AW480 units. This kit comprises a micro centrifugal pump, 10 Metres of food grade vinyl tubing and a check valve.
The P3 pump is to be wired to the pump terminals on the AW480 and then operates automatically when the compressor runs. (Temp. controlled) Passing through food grade materials, the fresh water is not harmed or consumed.
The ‘Air / Water’ switch allows the choice of condensing. (Switch off at night!)
Water cooling is said to increase power consumption. This may be true of other systems or methods, but is totaly wrong for the Ozefridge method.
The P3 water pump uses less than 3 watts/hour (1/4 amp!) yet reduces the compressor consumption by >18 watts/hour and decreases run cycle times by up to 34%. (At 40c)
The Ozefridge water cooling method greatly reduces overall power consumption without fear of electrolysis damage.
The P3 water pump is the centrifugal type and therefore much quieter, easier running and use far less power than the diaphragm types.

[Neptune's Gear]

Nope, that's correct - it is cooled by both, but if you switch on the water cooling, you'll find the fans produce almost no noticeable warm air. Actually my comment about cooling only the Electronics comes from the older model, but the water cooling is very efficent, so the air cool is virtually "off" if the water cool is ON.
I have found no reason to switch off the water cooling - ever. The pump for it is a very small and quiet Aquarium pump, so it is not an intrusive sound.
Now we are back on land for a bit, the Boat is at the bottom of the garden, on our marina, and we still use the freezer as spare capacity. Like a garage freezer. My Admiral thinks it is one of the single best upgrades we ever did to the boat. :-)

[Pelagic]

Thanks again for clarifying Matt.

I like the design concept and my 1,500 liter steel fresh water tank is part of the hull shell so this appeals to me as does the simplicity of hook up

Is your water cooling observations based on NZ ambient water and air temps?

Reason I ask is that I have a couple of installation choices for compressor one with more fresh air cooling but about 4m run to cabinet, the other more enclosed but less of a refrigerant run.

My location can have + 33C air temps and the estimated Sea Water surface temperature ranges from 27°C to 31°C.

Anyone observed the water cooling performance it in those kind of Temps?

Peter Mackay from Ozefridge has been great at giving me technical solutions; I just need to confirm User experience.

[Neptune's Gear]

Yup, we had 40 deg C in the cabin, and 34-35 deg C water temps in SE Asia for a bit. The water was so hot it was killing the local coral.
The Ozefridge still performed as described. I'd go for the short run, and use the water cooling if I were you!

Peter is great, and is the reason I bought mine, as he was the only one I could find who talked about the capabilities in a believable (engineering wise) manner. If you buy it direct from him, make sure you tell him I helped with info!!

[Pelagic]

Thanks Matt, I appreciate every customer and supplier freely sharing their experience within the spirit of this Forum

[travellerw]

This system seems awesome and Matt had done a great job selling it.

but... I had a thought.. Why couldn't you hook up any other water cooled system the same way? Is there something special about this system that allows it to hook up to your fresh water for cooling? Why can't you do that with a Adler/Barbour system?

This is not about saving money, cause I don't think a Adler/Barbour would be any cheaper. It was just a thought!

[Pelagic]

Good question…. I don’t know enough to answer but I am guessing that it starts with the heat exchange design of the condenser and how much they depend on water cooling versus Air cooled.

Unlike other water cooled condensers, the refrigerant is not in direct contact with the water galleries and therefore can’t be lost or contaminated due to electrolysis or corrosion.
This condenser is best water cooled by re-cycling water from the vessel’s fresh water tank with the pump kit supplied. ( Using raw water is not recommended and will cause harm eventually)
The Ozefridge condenser is conformal coated to resist air borne corrosives.
Water cooling is essential on twin plate freezer systems and highly recommended for all systems specially if used in the tropics or other hot climates.


Ozefridge seems to offer both options with their large twin Fan, but obviously with limitations if you are in the tropics and a twin plate installation. (my case)

I remember another thread where someone was suggesting that the refrigerant coil be actually immersed in the fresh water tank.... Concerns about balance and varying head pressures seemed to be the concern with that idea.

Interesting stuff!