Full on fridge redesign – 4 Aug

Today started with an hour of running the motor at 1700 rpm to get 100amps out of the alternator. I can get more but i discovered the temp sensor had fallen off (or melted off) the balmar 150amp alternator. this is supposed to drop the alternator to 50% output when it gets too hot. without it running at max output with very low batteries i am worried i may fry it and then be really sol. i do have a backup 100amp alternator but really dont want to add that the my list.

so after aimee did yoga and i made coffee with the inverter aimee headed to town to get the massive 4 ft x 8ft sheet of foam and i got started on the fridge. as you can see from the photo there is very little room between the back of the fridge and the wall basically about an 8×8 inch compartment with previously only ventilation on one end under the sink. so to begin with i rotated the radiator portion 45 deg so it was now sucking off to the side and pushing off to the other side rather than pulling from the back of the fridge pushing into the wall. the required unbolting the radiator and bending the tubes. do this very carefully!!

second i added two .2amp cooling fans larry had brought out years ago to fix the charger/inverter. i added these in the same circuit as the existing fan so they are on when the other fan is on. hopefully this .4 amp will not overload whatever relay or mosfet is controlling the fan. i also added a duct to bring the hot air out from the area behind the fridge to the grilled door to the under sink compartment

by this time aimee had arrived back on shore with the insulation. i headed in with some cutting equipment to break the sheet up into smaller chunks with. we cut it into 3 foot sections and piled it in the dingy. aimee observing the mayhem on palapa recommended we return to shore for lunch, given the fridge was half out of the wall blocking galley access and making it impossible to open the fridge this seemed like a good plan. following lunch she offered to do laundry and or work on the internet on shore basically anything to get off the boat.

next i got going on insulation. the compressor is super hot and right next to the back of the freezer compartment so i decided to “move” this as well so i could insert a 2 inch piece of foam between the compressor and the fridge. this required more bending of tubes and drilling to re-anchor the compressor.

once the compressor fan and radiator and duct where locked down securely on the back of the fridge i methodically began measuring and cutting section of foam and fitting them in. of course i discovered there was actually only 1.5 inches of space behind the fridge so once i added the 2 inch foam i could not get the fridge all the way back in. no problem, i thought, i found some longer screws and figure i will just get some 1/2 inch trim stock when i get done with everything else. this gives another 1/2 inch in back to work with.

i managed to get everything crammed back into the compartment only once ripping the ducting off and having to start over. i now get nice cool air flowing over the radiator and hot air blowing out through the sink door grill. my only concern is the compressor is very hot. the good news is now at the min setting it is not running near as much as before. i wish i had taken some duty cycle measurements before and after but alas getting the best result is more important than knowing exactly what the improvement was!

we had another happy hour on waka iere and mad plans to head over to “rogers bar” on hog island tomorrow. that is if i can get the solar panel hooked up and the final insulation under the fridge with no unanticipated problems. we are scheduled to haul out in 2 days so this will be our last “relaxation” before being on the hard my favorite!

Cheers – Roger