Operating instructions
7
Differential Pressure Measuring Kit
EN
5.2.2
Functional test at KEMPER Backflow Preventer type BA
(primary check valve and bleed valve)
5.2.2.1
Functional test of the primary check valve
Close the stop valves in front and behind the Backflow Preventer.
Slowly release the pressure by opening the isolating valve on the test hose B and
pay attention to the differential pressure.
The pressure difference increases
until the primary check opens. The bleed valves has to remain close.
Close the isolating valve on the test hose B.
Now the pressure difference has
to be constant.
5.2.2.1
Functional test of the bleed valve
Open the stop valves in front and behind the Backflow Preventer and release air
via isolating valves on the test hoses.
Close stop valves in front and behind the Backflow Preventer.
Slowly open the isolating valve on the test hose A to release pressure and pay
attention to the pressure difference and the bleed valve.
The bleed valve has
to open before the pressure difference drops below 140 hPa. When the
bleed valve reacts, the pressure difference slightly increases before it
slowly starts to drop.
Close isolating valves on the test
hoses. The bleed valve must now be
closed too.
Close test valves A and B on the
Backflow Preventer and remove the
differential pressure manometer.
