Typical insulation in a reefer truck is two inches of polyurethane which has an R-value of 12.
Mike Jay wrote:The water heater I looked at with a 2" shell is probably closer to the R12. Thus the hot heater would use 33 watts and the cooler one would use 21 watts.
No matter how many women are assigned to the project, a pregnancy takes nine months. Much longer than this tiny ad:
All of the video from the Eat Your Dirt Summithttps://permies.com/t/106759/video-Eat-Dirt-Summit