4
Description of function
The multiple function valve combines all of the following functions:
Overflow
n
n
Pressure maintenance
n
Venting
n
Drainage
This safety-relevant component serves the purpose of protecting the piping system and
the metering pump and permits safe and reliable commissioning and maintenance of the
system.
During normal operation, the metering pump operates against the counterpressure set on
the multiple function valve.
Counterpressure in the metering line is discharged via the bypass line if it rises above the
overpressure set on the multiple function valve.
The metered fluid continues to be conveyed through the bypass line until pressure in the
metering line has again fallen below this value.
Description of function
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417101434 Rev. 5-05.2019