Ecolab MFV PPFP050 G3/8-G5/8-21 Manuel D'utilisation page 61

c) Vent function
Suction aid for first-time startup of the pump.
NOTICE!
If the knob is turned by more than approx. 20°, the knob snaps back to the
initial position.
d) Emptying function
Emptying and therefore relief of the pressure line at machine standstill.
NOTICE!
If the two knobs are turned by more than approx. 20°, they snap back to the
initial position.
By turning knob 2 to the right (pressure relief valve) the
metering counter pressure is relieved.
The metering line is emptied by turning the two knobs 1 and 2.
21
Function and Use
417101382 Rev. 07-05.2019