Wallingford Plm+Htg
A loop vent is not a circuit vent.A loop vent is a half ass attempt at an island vent created by old timers.I say if your going to use a loop vent then you might as well go the easier way and use a s trap since niether will assure you of trap seal.All the s traps I see these days were put by oldtimers.I’m sure they were just confused because they spent too much time by the lead pot.
