That is an excellent question for me to look in to.
I did this with 2 spare junk fridges and the intention to change them out if i need to ( im just pushing for a single set of clones so a few weeks of life is plenty)
But i did find myself playing with the idea of tube lengths and the rate of btu loss of the res itself and you asking is exactly what will make me check (its literally the reason im here) sooooo here we go.
0_o
8.33 BTU
A British Thermal Unit (BTU) is a measurement of heat energy. One BTU is the amount of heat energy required to raise one pound of water by 1ºF. Water weighs 8.33 pounds per gallon so we can calculate that one gallon of water requires 8.33 BTU to raise the temperature 1ºF.Jul 3, 2012
OK so im guessing without checking that my pump is moving about 3 gal a min (ill check later)
I have about 10 gal in the res (ill check and measure for accuracy later 0_o )
so about 80 btu to drop the res 1 F (the temp controller is set for 1 F diff)
any ideas how much fluid 60 ft of 1/2 in ID tubing holds? (ill check later)
the fridge can average how many btu an hour? (ill check in a bit)
the 120 site clone machine is not insulated …yet
I think that’s most of the factors. (i can think of)
OK i have tonight’s entertainment.
0_o