Troubleshooting; Service Policy - Walchem EZ Series Instruction Manual

6.0

TROUBLESHOOTING

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.
Problem
Pump does not start
Pump does not prime
Output fluctuates
Liquid leaks
7.0

SERVICE POLICY

The EZ Series electronic metering pumps have a 2-year warranty. Contact your Walchem distributor for service.
Possible Cause
Faulty wiring
Improper voltage
Electronic control unit is damaged
Air in suction tubing
Valve gasket is not installed
Valve set assembly direction is wrong. Reassemble valve set
Pump is air locked
Suction or discharge valve is clogged
with foreign matter
Ball stuck to valve seat
Suction or discharge valve is clogged
with foreign matter
Air is trapped in pump
Overfeeding
Diaphragm is damaged
Fitting or coupling nut is loose
Pump head is loose
Diaphragm is damaged
O-ring or valve gasket missing
Corrective Action
Correct wiring
Connect to proper voltage source
Replace control unit (Contact distributor or
factory)
Reroute suction tubing to eliminate air trap
Install valve gasket
Open air vent valve
Disassemble, inspect, clean
Disassemble, inspect, clean
Disassemble, inspect, clean
Open air vent valve
Install injection valve or back pressure valve
Replace diaphragm
Re-install (see section 2.3/2.4)
Tighten pump head bolts
Torque: 19 lb-in (2.16 N-m)
Replace diaphragm
Install o-ring or valve gasket
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