Just did some testing on the 165qt mash tun cooler with CPVC manifold I hooked up today.
One happy thing -- with a 100qt hot water test -- it held the temperature to a 6.5 degree drop in 10 hours -- so less than 1 degree per hour, which works for me.
However, when I drained the cooler -- which uses a CPVC manifold with slots on the bottom 1/3 to 1/2 of the 3/4" tubing inside and a drain pipe that has to lift above the level of the manifold in order to exit -- it leaves between 10-11 quarts of water in the cooler after a full level drain.
Now I know that when it has grain in there, the amount of liquid that is lost will be MUCH less than 10-11 quarts. But, does that seem reasonable?
Wondering if there is a design flaw.
If not -- how much free draining wort will be lost where there is a grain bed in there (in other words -- what is the volume of water that can be drained from 10-11 quarts of saturated grain/wort combo.