Marine Refrigeration Systems.. .. Shipped Direct World-Wide.
MARINE REFRIGERATION: Installing a 12 volt eutectic system, a simple DIY project.
OZEFRIDGE SPECIFICATIONS:
All fixings are stainless steel bolts with captive nut-serts. Splash proof auto 110 or 240 VAC to DC converter (Option)
Built on and housed with polished stainless steel. 12VDC Compressor 3.5cc variable speed with soft start.
Controller panel can be located remote. Triple pass air & water cooled condenser.
Water proof digital controller. Water in / out nipples. (AW490 unit only)
LED fault light indicator. 12VDC Power in terminals with zorb.
On-Sleep switch. Pump circuit fuse. (AW490 only)
Control bypass to manual. Pump (AW480 only) and probe terminals.
ECO2 On-off switch. Proper flared 032 filter dryer. (Inside)
Condenser speed selector. Refrigerant suction pipe connection. (Blue)
Twin variable speed fans. Refrigerant liquid line connection. (Red)
Front and rear fix down points. ECO2 automatic power management system.
Shut off valves with Schrader access. Proper refrigeration flare nut pipe couplings & dust covers.
Major components of the condensing unit: Compressor: Ozefridge model BE90:
This 3.5 cc variable speed compressor is the most powerful available for these systems.
Being variable speed it can be set to rotate at a speed suitable for the task and usually
that is at much lower RPM than others.
For comparison the Secop (ex Danfoss) BD35 is 2.0cc, the BD50 is 2.5cc and the BD80 is 3.0cc all which have to operate at a proportionately faster speed to get the same job done.
Using a larger capacity, slower compressor is not less efficient in fact often more efficient.
A larger compressor has a higher amp / hour run rate but operates for proportionately
less time to get the same job done. The real benefit of the more powerful compressor is
its ability to convert more electrical energy into thermal energy when power is abundant.
The BE90 has a six stage soft start Motor Driver Module. (Black box!). This allows the
compressor to ramp up to operating speed slowly and not like the DOL (Direct on line)
that are trying to go from zero to near maximum speed instantly.
This soft start Motor Driver Module has been the greatest advance in DC refrigeration
as the start up stress is removed and the dreaded 'Black box failures all but eliminated.
The BE90 compressor now has a FIVE year warranty >>>
Spike Arrester:
Erratic high voltage transient voltages (spikes) can originate from various sources elsewhere
resulting in damage to electrical components. This has been a common cause of damage to
Motor Driver Modules, thermostats and fans all common on marine refrigerators.
Ozefridge fit a 'Voltage clamp' AKA 'Zorb' or Voltage arrester. This device 'kills these high
voltage spikes protecting the fridge and all electrical devices connected to the power supply.
Condensers Air cooled A490 and the Air / Water cooled AW490:
The Ozefridge engineered condenser is fabricated using Cupro Nickel tubing and conformal coated for maximum protection.
The heat exchange area is a massive 60mm x 180mm x 180mm with 50 fins.
The A490 condenser has three coil passes and 5400 square CM of fins for heat dissipation.
The AW490 condenser has two refrigerant coil passes and a separate water coil pass. It also has a total 5400 square CM of fins for heat dissipation.
The air / water cooled condenser allows water to accept heat via the fins and therefore the water gallery has no direct contact with the refrigerant galleries avoiding the common issues of electrical corrosion. (Commonly referred to as electrolysis) See sketch left. Refrigerant travels via the purple and yellow tubing while water traverses the separate green coil.
Another unique benefit of the Ozefridge deigned condensing is its ability to maintain a condensing temperature within the engineered range and not just subject to the ambient at the time.
Thermostat control (a secondary function of the systems main controller) varies the fan speed on the A490 model and also introduces the micro pump to assist with water cooling on the AW490 as required. This feature helps provide a more efficient conversion of electrical to thermal energy.
Maintaining the condensing temperature between desired parameters avoids over or under condensing and contributes to far greater system efficiency.
Regardless of how hot or cold it is, with controlled condenser temperature the Ozefridge system will deliver similar performance and economy.
Controller panel:
The front mounted controller panel is stainless &
can be located up to three metres from the unit if
preferred using the optional 'Remote panel kit.
The kit includes a SS cover plate to cover for the
removed controller, 2 metres of cable with waterproof
plugs to match.
The digital controller with memory is water proof
and has a well lit temperature read out.
Condenser temperature: By pressing the down arrow the systems high side (condenser temperature) can be read. This is most useful diagnostic tool as the state of the condenser relates directly to the systems performance often avoiding the need for gauge hook up.
Eutectic Plates:
We offer three 'foot-print' sizes all of which can be ordered for 'Landscape or Portrait and 40 or 60mm overall thickness.
Overall size are:
Model P33-29-6 = 332mm x 292 x 40 or 60 mm overall. Model P40-33-6 = 390mm x 330 x 40 or 60 mm overall.
Model P53-35-4 = 530mm x 352 x 40 mm overall. Model P53-35-6 = 530mm x 352 x 60 mm overall.
This thinner plate suits freezers where 'twins are needed.
Eutectic Plate Mounting / offset:
All plates have a 1.2mm stainless steel rear mounting plate which is specially profile cut to
provide air access to the area behind the plate increasing surface heat absorption area.
Note all dimensions are overall and include the air space behind the plate.
The two smaller plates have eight mounting holes and the larger plate has ten.
All packages include a 24 page owners manual and an install kit including stainless steel self taping screws for plate and unit fixing.
Lots of possibilities:
Seldom are two projects the same! Therefore we believe it is important to interact so we can offer equipment that provides adequate and economical refrigeration, suits the space, has pipe arrangement to suit and has desired options / configuration for your project.
To start this obligation free process we need details of your project: Click here to complete and forward details:
Here are some various concepts:
Right: Refrigerating a fridge only (+2c to +4c) usually requires just a single
eutectic plate the size of which can only be determined once the project is
assessed.
Usually a cabinet up to 110 litres uses a P33-29-6, cabinets to 170 litres use a P40-33-6 and up to 280 litres use the P53-35-6
(The above is a guide only, assuming properly insulated top opening cabinet)
Left: Combination fridge / freezer systems are the most complex as there are many individual cabinet
arrangements, sizes etc.
Usually these combination cabinets have a high refrigeration heat load and are best suited to use with an AW490 air & water cooled unit with its superior cooling capability.
Right: This combination fridge freezer cabinet has a top opening freezer at the top and front opening fridge underneath. Twin thin P53-35-4 eutectic plates refrigerate the freezer while a digitally thermostat controlled Thermo-fan looks after the lower fridge compartment maintaining accurate temperature with
readout.
The AW490 controller panel and the matching Thermo-fan controller panel
were located remote as in the sketch above.
Left: This freezer cabinet is serviced with twin P53-35-4 portrait mounted eutectic plates.
Note a spare twin wire (red) is run along with the probe cable and pipes inside black sponge insulation.
This 'spare' twin wire is supplied with all Ozefridge plates and makes powering a light or circulation fan easy if required at a later date.
Note: All Ozefridge eutectic plates are fabricated, not welded, to avoid fatigue cracks. They all have their pipe entry, probe entry and brass filler at the top. Being above the eutectic liquid level avoids any possibility of a hydraulic effect at those points.
Important note: Some countries including Australia, require that R134a gas is only handled by licensed trades-persons.