21:4 Cleaning the machine
Repair instructions
Deposits of scale in the diaphragm may prevent the valve from closing or
opening correctly. Therefore, the valve should be cleaned at specific inter-
vals dictated by operating conditions and water quality.
The valve fails to open or close correctly
• Checkthatthemotorhasthecorrectsupplyvoltage.
• Checkthattheplungerrodcanmovefreely.
• Checkthatthediaphragmisnotcloggedbydepositsofscale.
Comment
When replacing the motor:
Brown cable: 60 Hz
Blue cable: common.
Black cable: 50 Hz
Tensioning the return springs
With the valve housing removed:
- Turn the return spring so that the spring's ''tongue'' is resting against
the stop screw.
- Place the valve housing over the return spring so that the pin on the
spring fits into the inlet of the piston rod. (NOTE: The piston rod shall
be fitted so that its input is longitudinal with the housing.)
- Then turn the housing one turn in a clockwise direction. (In this way,
the spring's pin will be threaded into the piston rod. The spring is then
tensioned approximately 1/4 turn, as a result of the rise in the piston
rod.)
Stop screw
Spring tongue Return spring's pin