Integrate..... ;)

Seriously though, a house is tricky because of so many variables. Sunlight, 
leakage, conduction, heat generating items inside, etc. Formulas will not 
represent reality when you get done. That's mostly because the amount of each 
varies each day too, if you're after some constant. Windy days promote leakage, 
sunny days heating from the roof, weekends in and out the door.... and so on.

It might be best to put a temperature sensor in the attic, the house, and the 
shade outside, a relative measurement of sunlight somewhere, and maybe wind 
speed. You should then record use of the oven, stove, hair dryer, etc. By 
graphing those you can curve fit a possible equation for your house. I've done 
a little of that with a wireless weather station, but without a sunlight 
monitor it's useless other than being interesting. Sunlight can really change 
things here.

Also track on-time to the air condition unit. Use your equations and some 
assumptions about house mass and compare with the energy used to extract it 
(accounting for efficiency of the A/C). Tweak till you get close. ;)

Other variables include the foundation and its ability to sink heat, sunlight 
heating through windows, mass of the house and interior and their thermal 
coefficients, etc. It's just too complex unless you treat it as a system, and 
even then there are a lot of variables.



Neil Cherry wrote:
> So as not to hi-jack the thread, I'll start a new one as this is
> not directly related to refrigerators.
> 
> Where can I information on heating and cooling with respect to
> time? I remember from my chemistry and physics course information
> about heating but I don't recall time being part of the formula.
> The reason for the interest is the heating and cooling of my
> home.
> 
> Thanks
> 
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