Diaphragm Pump – Troubleshooting Guide

1. What to do when the diaphragm pump is not starting.

Cause:
⦁ Air connected to Exhaust
⦁ Discharge piping obstructed or shut off valve closed.
⦁ Shaft Seal failure
⦁ Diaphragm ruptured
⦁ Air Valve System malfunction

Solutions:
⦁ Re-connect to Air Inlet
⦁ Clean the line or open the shut-off valve
⦁ Replace New Shaft Seal
⦁ Replace Diaphragm
⦁ Check carrier for freedom of movement and all seals in chest assembly. Clean or replace.

2. What to do when the diaphragm pump is operating but no discharge.

Cause:
⦁ Suction Line Leakage
⦁ Valve ball not seating correctly or damaged
⦁ Suction Strainer or Line clogged
⦁ Excessive Suction Lift
⦁ Diaphragm ruptured

Solutions:
⦁ Check and Repair
⦁ Remove obstruction / replace balls or seats
⦁ Clear the manifold or the piping
⦁ Shorten Suction line
⦁ Replace Diaphragm

3. What to do when intermittent stroke rate happens.

Cause:
⦁ Shaft Seal failure
⦁ Air Valve System malfunction
⦁ Over lubrication
⦁ Valve Ball obstruction or not sealing

Solutions:
⦁ Replace New Shaft Seal.
⦁ Check carrier for freedom of movement and all seals in chest assembly. Clean or replace.
⦁ Clean the Air Valve System and shaft bushing.
⦁ Remove obstruction / replace balls or seats.

4. What to do when fluid is discharged from air exhaust.

Cause:
⦁ Loose Outer Piston
⦁ Diaphragm ruptured

Solutions:
⦁ Re-Torque to manual specification
⦁ Replace Diaphragm

5. What to do when there is an erratic flow.

Cause:
⦁ Diaphragm ruptured on one side
⦁ Suction Line Leakage
⦁ Air Valve System malfunction
⦁ Shaft Seal failure
⦁ Valve ball not seating correctly or damaged

Solutions:
⦁ Replace Diaphragm
⦁ Check & Repair
⦁ Check carrier for freedom of movement and all seals in chest assembly. Clean or replace.
⦁ Replace New Shaft Seal
⦁ Remove obstruction / replace balls or seats