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never trust a robot you didn't make
Wednesday, December 14 2005
I entrusted an automatic outlet gizmo with a built-in digital clock with the task of turning on the heat tape this morning in the hour before solar sufficiency so the fluid would be warm enough to flow and I'd be able to collect some heat for the basement slab. But of course it didn't work because it's a piece of shit sent over on a slow boat from China and I bought it too long ago to even remember where it came from. Perhaps I should coin another law, "Never trust a robot you didn't build yourself." As a consequence, my heat tape didn't begin heating until solar sufficiency was about to begin. But the poor pump struggled for an hour and a half against the ice dams in the hoses and didn't break through t until about noon. I'm not really happy with the way I ran the heater tape either, but my options are kind of limited given that I never thought I'd be resorting to such a made-for-boneheads technology. My thinking about heat tape has always been that it's a hack for dealing with moronic plumbing routing decisions or (worse) the foolhardy delay of insulation installation. The only reason I'm using heat tape is because I'm trying to use an outdoor hydronic solar panel when temperatures are down near zero degrees Fahrenheit. I was kind of hoping this winter was going to be either mild or typical, with this sort of weather not happening at all or else coming in the time when it usually does: the last two weeks of January. The days are so short now that my solar collection day only runs from 11am until about 2pm. And on these beastly cold days I've been noticing that, while the mornings are crystal clear, a creamy layer of altostratus inevitably forms by around noon, greatly diminishing my photon harvest. So, while the panel may briefly hit temperatures of 170 degrees (some 160 degrees above that of the outdoors), an hour of it doesn't really do much to raise the temperature of the slab. For days like these it would make more sense just running that heat tape under the basement carpet.
In a manifestation of the toll this cold weather is taking on average house temperatures, today the basement slab dropped from 55 to 53 degrees (remember, I only have two degree granularity on the meat thermometer I'm using to take these measurements). Only a few days ago water leaving the slab was at 57 degrees. I definitely need to get a more accurate thermometer so I can precisely gauge the number of joules my solar panel is collecting in a typical day, thereby allowing me to determine whether it is wildly inefficient or not. (That exercise the other day where I calculated the specific heat of the basement slab is going to prove very useful.)
Gretchen and Julius, aka "Stripey," in the teevee room.
Sally at the top of the stairs in the teevee room. That's the door to the laboratory behind her.
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