Our first step into "vacuum" was a single Guzzler. We had over 2000' of 1" and 3/4" mainline and serviced about 375 taps. We constantly saw 24-25" of vacuum. It took awhile to build the vacuum. We wanted to expand to more mainline and add a couple ladders so we went to a vacuum pump. I think the guzzler is a lot like an RO is to processing sap...it is a simple and easy method to expand. Speaking of ROs if you don't have one you will truly see the benefit once you add a guzzler...we did.
Mike
Tapping since 1985 (four generations back to early to mid 1900s). 200-250 taps on buckets and then tubing in the mid 90s. 2013- 275 taps w/sap puller 25 gal. 2014-295 taps w/sap puller 55 ga. (re-tapped to vacuum theory) 2015-330 taps full vac. 65 gal, 2016-400 taps 105 gal, 2017-400 taps 95 gal. 2018-additional 800' mainline and maybe 400 new taps for a total near 800 taps. 2x6 Leader WSE (last year on it) supported by a 250 gph RO.