AODD Pump Common Problems and Troubleshooting Tips

Air operated double diaphragm pumps are widely used in the food and beverage sector. They are well-suited to pumping viscous goods such as olive oil and peanut butter. Because of their basic air-powered functioning, they are often quite dependable. However, like with any process equipment, several tips and practices help you get the most out of your AODD pump operation.

Processing may slow to a trickle if the pump is not operating well. The sooner repair crews can restore pump functionality, the less expensive the disruption. This article provides a practical checklist for quickly troubleshooting an AODD pump.

Of course, before you begin troubleshooting, make sure all fasteners are snug and properly torqued. If tightening fasteners does not improve pump performance, follow the manufacturer’s troubleshooting instructions.

If the incident occurred on an existing pump, ask the operations staff the following question: Has the application changed? If yes, confirm that operations talked with the maintenance manager.

Common Issues With AODD Pumps and Their Solutions 

Problem: The pump fails to cycle or cycles and then stops.

You may have this issue if there is no air exhaust or if the exhaust air is continuous without cycling.

Solution 1: 

• The first tip is to ensure the air supply pressure exceeds the system head. 
• Increase the pump’s inlet air pressure. Most diaphragm pumps are intended to have a pressure ratio of 1:1 at minimal flow.
• Remember that the inlet air pressure must exceed the system head. 

Solution 2: 

• The second tip is to inspect the AODD pump’s air distribution system. 
• Refer to the air valve portion of the pump’s service manual. Disassemble and check the primary air distribution and pilot valves. 
• Also, inspect for bent or missing pilot valve actuators. Check the air valve and intermediate gaskets for appropriate alignment. 
• And, follow the instructions given in the product manual to assemble the pump’s components.

Solution 3: 

• The third tip is to check the pumped fluid in the air exhaust silencer/muffler.
• Disassemble the Air Operated Double Diaphragm Pump chambers and check for diaphragm rupture or a loose diaphragm plate assembly.
• Inspect the air exhaust silencer muffler. Before a full blockage, the pump’s output may gradually decrease.
• To clean or de-ice the muffler, remove the screen. Once done, reinstall the muffler screen.

Solution 4: 

• Make that the pumping chamber is not clogged.
• Disassemble and check the pump’s wetted chambers. Remove or flush any impediments.
• Check that the discharge line is not clogged.
• Also, check for a blockage in the AODD pump valves, manifold, or discharge line valve.

Problem: The pump cycles but does not create any flow.

If the exhaust air sounds smooth and uniform yet does not flow, there may be a problem.

Solution 1: 

• Check for excessive suction lift in the system.
• For lifts that exceed the pump’s declared limit, which is typically 20 feet (6 meters) or less, fill the pumping chambers with liquid to prime the pump.

Solution 2:

• Make sure the suction line of your Air Operated Double Diaphragm Pump is not clogged.
• Remove or flush any impediment. Check and clean all suction screens and strainers.

Solution 3:

• Check for suction-side air leakage when the liquid supply is located beneath the pump.
• Also, check all suction-side gaskets and pipe connections.

Solution 4:

• Check for worn, misaligned, or blocked check valves or seats.
• Look for the check valves and seats for wear or chemical attachment, and ensure correct seating. 

Problem: The AODD pump operates, but the flow rate is insufficient.

If the exhaust air cycles more faster than usual, you may have a problem.

Solution 1: 

• Check for excessive suction head pressure in the system. 
• Install a back-pressure mechanism in the air exhaust if the water level exceeds 10 feet (3 meters).

Solution 2:

• Ensure the air supply pressure or volume does not exceed the system head limitations.
• Reduce intake air pressure and volume to the pump as determined by the AODD pump’s stated performance curve.

Solution 3:

• Make sure your suction line isn’t too short or constricted.
• Install a bigger suction line and connector. Your pump must meet or exceed connection guidelines. 

Talk to an AODD Pump Expert

AODD pump components, like any other piece of equipment, can fail prematurely if not used properly. To minimize downtime, choose an AODD pump manufacturer that provides excellent technical support.
Nirmala Pumps provides excellent services to its clients throughout the life of their pumps. Contact us if you have any problems with your Air Operated Double Diaphragm Pump.