Posted 11/24/2021 14:54 (#9338883 - in reply to #9337978) Subject: RE: Winterizing a barn
No easy way unless it was designed to drain. Open up the first and last one, and blow through them, or even a shop vac might work if it's only 40" deep, fill it with RV antifreeze, and cap it. If you're sure the shut off valve is not leaking, then you could get away with a gallon of antifreeze, then blow that out and add another gallon, or even half a gallon at a time.
If it's all plastic pipe and plastic fittings, use salt, or calcium chloride from old tires.