I have a run of 3/16 that doesn't have a whole lot of slope, maybe 1/8 inch per foot for 200' and then drops 10-12' after the last tap. The only time I have checked it & it wasn't running it was well below freezing, it has never stopped otherwise. Very happy with it so far. Going to put the Vac gauge on it tomorrow to see what I am actually getting. It has 17 taps on it
You may actually have more drop than you think, or possibly faulty gauges.
sugarsand
4x12 arch
new custom flues
New custom front pan
600 buckets town trees
1500 3/16 taps
D&G filterpress
16x32 3rdgen canner
member NYMPA
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2015 Mahindra 70hp