Parker AFL Series - Troubleshooting Pneumatic Issues

7
Parker Autoclave Engineers
Instrumentation Products Division
Erie, PA USA
www.autoclave.com | Cat. 02-9309ME
C. Maintenance instructions are supplied with appropriate
rebuild kits. Kit part numbers are listed on the assem-
bly drawing.
Section 11.0
Trouble Shooting - Pneumatic Section
Problem: Pump will not operate with low air pressure.
Cause: Excessive friction of o-rings on the spool valve has
increased the pressure required to move spool.
Solution: Replace and lubricate the o-rings on spool
Problem: Pump can only be actuated at high air pressure.
Cause: Air is leaking through the o-rings between
the end cap and air cylinder.
Solution: Replace and lubricate o-ring on lip of the
end cap.
Problem: Pump will not run and air escaped through
the exhaust mufer.
Cause: a) Spool valve o-rings are leaking.
b) Spool sleeve o-rings are leaking.
c) Outside o-ring(s) on air piston(s) is leaking.
d) Seal between air piston and liquid plunger
is leaking.
Solution: a) Replace and lubricate spool valve o-rings.
b) Replace and lubricate sleeve o-rings.
c) Replace and lubricate air piston o-ring(s).
Before attempting to disassemble the pump or loosen
ttings in a pressure system, be sure that liquid
pressure has been totally vented.
!
WARNING
Before attempting to perform maintenance on the
pump, assure that air supply pressure is shut off
and vented from the pump.
!
WARNING
d) Replace o-ring on bottom plunger (two piece
plunger designs), or add Loctite 2760 thread
locker with sealant on plunger threads (one piece
plunger designs).
Problem: Pump will not run and air escapes through
the pilot valve vent in the bottom end cap.
Cause: Pilot valve gasket or o-ring is not sealing in
the bottom cap.
Solution: Replace and lubricate pilot valve gasket
and o-ring. If necessary, also replace the
tappet rod.
Problem: Pump operates at a high frequency and
short strokes.
Cause: The top or bottom pilot valves are defective.
Solution: Replace and lubricate both pilot valve gaskets
and o-rings. If necessary also replace the
tappet rods.
Problem: Air leaking at isolation chamber drain connection.
Cause: The rod seal and/or the o-ring on the seal retainer
is leaking.
Solution: Replace and lubricate both the o-ring and rod
seal assembly.
Problem: Pump functions slowly or doesn't operate at all.
Cause: a) Condensation from air supply is freez-
ing the spool valve.
b) Air mufer is clogged.
Solution: a) Stop pump for a short period and re-
place or add a mist separator in the air line.
b) Clean or replace air mufer.