6
Maintenance
Servicing the Proportioning Valves
78
Accela Pump Hardware Manual
Thermo Scientific
Occasionally, after extended periods of disuse, the free-floating piston inside the
proportioning valve freezes against its sapphire seat. When this occurs, dislodging the frozen
valve requires a greater mechanical force than the magnetic field applied by the actuating coils.
You can dislodge the frozen proportioning valve with the proportioning valve tool supplied in
the accessory kit. This tool fits through the solvent inlet in the end of the valve face (see
Figure 66
).
Y
To dislodge the frozen valve inside the proportioning valve
Push the tool (which is a piece of stainless steel wire) into the valve until you contact the
piston, and then gently push the piston away from the valve face.
Figure 66.
Proportioning valve, shown with the valve tool
CAUTION
Do
not
disassemble the proportioning valve. If you disassemble the valve, send
the valve back to the factory for repair or order a new valve.
Valve tool
