Gardner Denver RGD Series Instruction Manual page 8

If power supply is not connected and unit is not
depressurized before disassembly, serious personal injury and
valve damage may result.
5. Remove hoses that connect the drain valve to the drain
discharge fitting and remove the valve from the drain valve
strainer.
6. Remove screw and washer from front of the drain valve.
7. Remove the power supply connector and gasket (with the
timer assembly if attached) from the solenoid coil housing.
Do not damage or lose the gasket.
8. Remove coil fixing nut from top of solenoid coil housing.
9. Lift solenoid coil housing off solenoid core in valve body.
10. Unscrew solenoid core from valve body.
Once the drain valve is disassembled, the following maintenance
can be performed.
1. Inspect internal parts of valve body; clean or replace as
required.
NOTE: Replace solenoid valve if component damage is
observed.
2. Remove debris from valve body.
3. Wipe solenoid core components with a clean cloth or blow
out debris with compressed air from an OSHA-approved air
nozzle that limits its discharge pressure to 30 psig.
4. Check that the plunger assembly is clean and moves freely
in housing.
5. If timer is attached to valve body, check electrical continuity
across timer assembly.
To reassemble the drain valve, reverse the sequence of
the preceding steps. After the drain valve is reassembled,
connect the main power supply to the dryer.
When the dryer is returned to service, check the drain
valve for air or condensate leaks; tighten connections as
required to correct leaks. Check the drain cycle; adjust
the timer according to the procedure in the drain valve
adjustment section.
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