P
AGE
19
OF
25
Connect the outlet from the Venturi pump to a pressure free drain using ½” OD PFA tube or
similar. CAUTION: This should be outside any enclosure or house, as the liquid discharged to
this drain in abnormal conditions can result in the discharge of the customers sample to this
drain which could potentially be hot and corrosive.
_____
Connect the air supply to the Venturi Sampler. The typical connection is ¼” Swagelok.
The air for the venturi pump is typically set to 5 bar. It has been found that 5 bar is the
optimum pressure for generating the best vacuum in the venturi sampler. Using a higher
pressure will not generate a higher vacuum.
The air for the purge is typically set to 3.5
– 4 bar. This pressure must always be greater than
the water pressure. If it is lower than the water pressure, then water can feed into the air line.
_____
Venturi pump
outlet
Venturi air, 5 bar
Air
connection
Purge air, 3.5-4 bar
