Maintenance and repair of the dryer
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Clean check valves and replace if necessary
Check valves are wearing parts and must therefore be cleaned every 12 months,
and replaced if necessary.
► Depressurise the dryer and shut it down (see page 39).
► Unscrew and remove check valves from pipe bridge. Pay attention to
different direction of rotation on upper (1) and lower pipe bridge (see figures).
Removing the check valves
► Dismantling and cleaning the check valves
► If necessary, replace the check valves with new ones.
► Then reinstall check valves in the pipe bridge.
► If no other maintenance work is to be carried out: Restart the dryer (see
page 40). Check that the connection is leak tight.
Cleaning solenoid valve bodies and replacing if necessary
Solenoid valve bodies are wearing parts and must therefore be cleaned every 12
months and replaced if necessary.
► Depressurise the dryer and shut it down (see page 39).
► Unfasten solenoid valves from the pipework.
► Remove the coil.
► Unfasten screws on housing and remove.
► Remove diaphragm and spring from housing.
► Clean all components carefully.
► After cleaning components, reassemble them. Replace any defective
solenoid valve with a new one.
► Replace the coil.
► Reinstall solenoid valve in the pipework.
► If no other maintenance work is to be carried out: Restart the dryer (see
page 40). Check that the connection is leak tight.
Maintenance work to be completed every 24 months
To complete the following maintenance tasks, you must dismantle the pipe
bridges and the vessels. We therefore recommend that you carry out these tasks
together.
