Incorrect adjustment of needle valve
Adjust the chemical dosing percentage as described in the section on adjustment.
By turning a disk containing five different holes, the desired quantity of chemicals can be determined accurately.
Every time the setting is changed, a spring load will result in a click that will indicate that the valve is set in the desired position.
Note that the figures on the metering valve do not indicate the concentration.
The concentration is measured according to the chemical supplier's instructions.