T&T: Vented loop

[Al Thomason]

The Vented Loop should go after the intake water pump, but before the bowl. 
Cut the hose from the outlet of the intake water pump (not the waste water 
discharge side!), run it up high to a vented loop, then back down to the 
inlet of the bowl.

This way the vent will be able to open under a vacuum that is a result of a 
failure mode (e.g., water siphoning in), vs. were it is currently installed 
and the normal action of pumping in water presents a vacuum.

-al-