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Operation and maintenance manual, Discfilter HSF2200-1/2F PFC
5.2.1 Level differences
The maximum permitted difference between
the water levels inside and outside the drum
is 350 mm during normal operation (see Figure
5.3). The recommended level difference is 150-
250 mm.
If an even flow after the filter is required, the
filter must be run with a small level difference.
The filter must be installed so that the
level difference in the event of operating
disturbances under no circumstances ex-
ceeds 550mm.
The filter must be run so that the level difference during normal operation does not exceed
350mm.
Prolonged operation with a greater level difference will significantly shorten the life of the
filter panels and other vital parts.
5.2.2 Operating mode HAND – Continuous rotation/backwash
Operation with continuous drum rotation and backwash. In this mode, the water level inside the
drum is kept virtually constant.
The level sensor and the automatic level control are disabled when
HAND operating mode has been selected.
5.2.3 Operating mode AUTO – Automatic level control
With level control enabled, drum rotation and the backwash pump are activated when the water
level inside the drum reaches the level sensor. If an external backwash water supply is used, the
level sensor can control a solenoid valve instead of a pump.
The water level inside the drum will vary when AUTO mode has been selected. The water level is
at its lowest immediately after a backwash cycle and then rises until it reaches the level sensor
5.2.4 Adjusting the level sensor
NB Prior to servicing, read section 2.7.
Place the level sensor 50–100 mm below the overflow wall. The optimal placement depends on
the turbulence of the water surface (see Figure 5.4)
Figure 5.3 Maximum permitted level difference during
operation.
