re: pool heating... random thought... techie answer
10 oct 2003
>>how fast some temperature rises has little to do with the steady-state
>>final temperature, which has nothing to do with thermal mass... it's
>>surprising how often people make this basic mistake.
>>if an ac provides 48k btu/h and a shaded pool has a thermal conductance
>>of,say, 1200 btu/h-f (eg a 30'x40' r1 cover), its final temp will be 48k/1200
>>= 40 f warmer than the outdoors, no matter how much water is in the pool...
>but it will only heat at about 1/3f/hour, as barry calculated.
it would heat a 6'x30x40' pool full of air 48k/(6x30x40/55) = 6.7 f/h, but
so what? :-) the thermal mass is completely irrelevant here. this kind of
calculation is utter nonsense.
>i think the 1200 btu/hr-f number is a bit low for a pool, where did you
>come up with this?
look again, 12 lines up.