I am currently searching out a new front loading compressor refer.<br /><br />The consumption numbers are all over the map. No two fridges, even those using the same compressor, claim the same consumption, either when running, or averaged out.<br /><br />Some list average consumption, some list consumption when the compressor is actually running. Some use watt hours........ect.<br /><br />None tell how the fridge is loaded, or what temperatures the interior was kept at during the testing, or if it was opened during the testing, or for how long, or if it was run inside an insulated cabinet that had good airflow over the condenser, or the humidity. All these factors together make huge differences in ultimate battery consumption.<br /><br />My old Norcold claimed 2.7 amps when the compressor was running. When new it was close to 3 amps. When it failed 5 years later it was right around 2 amps but running twice as long.<br /><br />My Norcold Fridge, up until a few months ago, averaged about 1 amp hour per hour over 24 hours, keeping the box at or below 38.5f in Southern California's very mild coastal climate.. Some areas by/on the door were a few degrees warmer. I had added extra insulation, and made sure the compressor and condenser were very well ventilated.<br /><br />I cannot recommend the Norcold/Engle compressor fridges. Their power consumption 'might' be slightly lower with it's different type of 'swing' compressor than the highly respected Danfoss compressors used by NovaKool, Vitrifrigo, Isotherm, Waeco/Dometic and TruckFridge. I will not know until I get my new fridge. There is little info on actual consumption over the long haul, but figure minimum 0.7 amp hours per hour to 2.0 in hot temps with frequent door openings.<br /><br />All the DC powered compressor fridges should be within 15% of each other, if not even closer. The biggest variance between manufacturers will be in how well the door seals, and the insulation type used.<br /><br />What I can report is that the Norcold compressor was loud and vibrated the whole van. I spent considerable effort in isolating the compressor from the fridge box, and the fridge box from the cabinet I built around it. I achieved a considerable measure of success, but still, when on the edge of sleep, the compressor kicking on would piss me off.<br /><br /> The danfoss bd35 compressor is silent in comparison. <br /><br />Whatever Fridge I do decide upon will have extra insulation added to the box, and the Danfoss compressor and condenser will have fresh air force vented across them, and out of the compartment where they reside to transfer the heat most efficiently and reduce duty cycle and therefore battery consumption. All the Danfoss compressors come with a fan to force air through the condenser. I just plan on using this fan to also evacuate the air from the fridge cabinet pulling in fresh air to maximize heat transfer.<br /><br />My Norcold was an AC/DC fridge. The AC/DC option on all Danfoss compressor models add 100$ or more to the price. I am going to get a DC only fridge and at a later date, add a high quality Converter, which will take care of charging the batteries and powering the fridge and any other 12 volt item whenever I have access to the grid.<br /><br />With a converter there is no real need for the AC option on the fridge, and you have a heavy duty battery charger.<br /><br /><br />Also, Isotherm makes a fridge with an "asu' option. $$$ It is basically an extra coldplate which freezes whenever battery charging voltages are sensed, like from the alternator or solar panels. They claim upto 30% more efficiency.<br /><br />Basically, turning any compressor fridge upto a colder setting when driving or the solar is kicking out the juice will have the same effect when it is turned back down when the charging sources cease. I did this regularly, but only after the solar was done fully charging the batteries.<br /><br />One can buy chest style portable fridges too with these same compressors. Since the cold air does not really spill out when the lid is opened, and the door seals are on top, they are more efficient. But they are less convenient and one usually keeps the door open for longer searching for and re arranging items, nullifying some of the advantage.<br /><br />
