for now I just snug fit them.
Last night 11pm-4am, with the unit off, I lost cooling
from 31 degrees to 47 degrees, which amounts to 3 degrees an hour.
I turned the unit back on at 4:30am. When I was awaken at 9:00 am, the unit was 33 degrees(4.5hrs), with an ambient of 69 degrees.
A few hours later the cooler was 29 degrees with an ambient of 81 degrees(52 degree difference).
At 4pm, the cooler was at 27 degrees(80 degrees ambient), and at 7:00pm(minutes ago), it was 28 degrees at 78 degrees ambient.
Still ... with the unit off, plus the added insulation
, I lost
16 degrees in 5 hours.
I still wonder if the peltier, when off, is making small amounts of electricity which could explain the high rate of cooling
loss(the peltier is still in a circuit even with the 120-12 volt transformer unplugged?).
I might try to manually insulate the turned off(?) peltier from the rest of the cooler to see what happens.
If any of this proves fruitful, I hope to have a unit that operates less than 50% of the time.
Years ago, I never had this much loss(when off). Since then, I added a larger fan to the internal heatsink. Maybe the fans are the resistance that is causing/allowing the peltier to make electricity?