Tough day today. First four hours went fine, but go figure, the second company shows up to watch, i notice my 1'' HDPE gravity line to my preheater is slowing down. As i'm finishing shaking hands w/ everyone, I watch the flow come to a dead stop. I signal my wife to get the "oh sh*t" bucket as I tell my buddy to go grab all the five gallon buckets he can find out back. Long story short, the sap was freezing up on its way from the tote which is about 30' away up on a retaining wall above the sugar house. Closing up like a clogged artery. I event tried pouring water from the hot tub down the line but it didnt help. We made it work by hauling 5 gallon buckets down to the sugar house. Got me thinking about redesigning the gravity flow system with a larger diameter pipe. Thinking about using 2'' PVC. Any thoughts on this ? Crazy cold today ...