27
6.0 TROUBLESHOOTING
Problem
Possible Cause
Corrective Action
Pump does not start
Faulty wiring
Correct wiring
Improper voltage
Connect to proper voltage source
Electronic control unit is damaged
Replace control unit (Contact distributor or
factory)
Pump does not prime
Air in suction tubing
Reroute suction tubing to eliminate air trap
Valve gasket is not installed
Install valve gasket
Valve set assembly direction is wrong.
Reassemble valve set
Pump is air locked
Open air vent valve
Suction or discharge valve is clogged with
foreign matter
Disassemble, inspect, clean
Ball stuck to valve seat
Disassemble, inspect, clean
Output fluctuates
Suction or discharge valve is clogged with
foreign matter
Disassemble, inspect, clean
Air is trapped in pump
Open air vent valve
Overfeeding
Install injection valve or back pressure valve
Diaphragm is damaged
Replace diaphragm
Liquid leaks
Fitting or coupling nut is loose
Re-install (see section 2.3/2.4)
Pump head is loose
Tighten pump head bolts
Torque: 19 lb-in (2.16 N-m)
Diaphragm is damaged
Replace diaphragm
O-ring or valve gasket missing
Install o-ring or valve gasket
7.0 SERVICE POLICY
The EZ Series electronic metering pumps have a 2-year warranty. Contact your Walchem
distributor for service.
CAUTION:
Before working on the pump, disconnect the power cord, depressurize the
discharge tubing and drain or flush any residual liquid from the pump head and valves,
using proper chemical handling techniques.
