The apparatus comprises a pressure pump and a valve coupled together in {HEAD ~ fluid communication} with each other and wherein the pressure pump has an inlet coupled in fluid communication with {TAIL ~ an air source} and the valve has an outlet coupled in fluid communication with the drain 
The apparatus comprises a pressure pump and a valve coupled together in { HEAD ~ fluid communication } with each other and wherein the pressure pump has an inlet coupled in fluid communication with { TAIL ~ an air source } and the valve has an outlet coupled in fluid communication with the drain
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH