AODD and EODD diaphragm pumps use the same basic pumping principle and handle many of the same fluids. But that doesn’t mean they suit the same process. One is driven by compressed air – the other by electricity.
If you have compressed air and single or three phase electricity on site, both pump types are an option. So what actually makes you select one over the other?
It usually comes down to how the pump needs to operate. Does flow stay steady or change? Do you need automation? How often will the pump run? What matters more – upfront cost or ongoing expense?
In this blog, we unpack how to choose between them.
The basic pumping action is much the same. The difference is what drives the diaphragms:
That difference affects how you adjust pump speed and flow, what you need on site and what it costs to run.
With an AODD pump, you control speed and flow through the air supply. A regulator sets the air pressure – while an airflow control adjusts how fast the pump runs. Once it’s set, changing the flow is usually a manual adjustment.
You can still automate start and stop with solenoid valves or float switches. For a simple transfer or a process with a set flow rate, that level of control is all you need.
EODD pumps give you more direct control of speed and flow – either at the pump or through plant automation. So, in practice:
In practice, the choice comes down to a few key points.
Having electricity doesn’t automatically make an EODD pump the better choice. If you already have plant air and the duty only needs simple, fixed flow control, an AODD pump can still make more sense. The upfront cost is lower – and the extra control adds little.
Both pump types can run continuously. The difference is operating cost – compressed air costs more to produce, so the longer the pump runs, the more an EODD pump’s energy efficiency starts to count.
An EODD pump is typically quieter – which makes a real difference where several pumps are running or workplace noise is already a concern.
Both pump types pulse. EODD pumps generally produce a less abrupt pulse, but the electric drive doesn’t remove pulsation altogether.
EODD pumps don’t cover the full size, flow and pressure range available with AODD pumps – so check the selected model against the required duty.
The better fit usually comes down to how the pump must operate, what you already have on site and how much control you need. Here’s where each option tends to work best.
| Use an AODD Pump When | Use an EODD Pump When |
| Compressed air is already on site | Flow changes with process demand |
| Flow stays fairly constant | Plant automation includes pump control |
| Simple control is enough | Compressed air is unavailable or expensive |
| Lower upfront costs matters more | Operating hours are long and energy efficiency matters |
| Portability is important | Lower operating noise is important |
Both pump types handle many of the same fluids – the better fit comes down to control, utilities and operating conditions.
Graco QUANTM AODD pump set up for drum transfer.
AODD and EODD pumps overlap across many industrial applications – but how each fits the duty can differ. Here are some common examples.
| Application | AODD Pumps | EODD Pumps |
| Chemical, paint and solvent transfer | Compatible materials and approval required | Compatible materials and approval required |
| Low-shear and viscous transfer | Check suction conditions and derating | Check suction conditions and derating |
| Tank, drum and general transfer | Common choice – especially for portable duties | Suitable where electrical power is available |
| Automated line and dosing | Supports added controls and instrumentation | Strong fit for automated control |
| Filter-press feed | Commonly used | Model and duty dependent |
| Hygienic product transfer | Hygienic AODD model required | Hygienic EODD model required |
AODD is usually the simpler choice where plant air is available, flow stays steady or portability is important. EODD becomes more attractive where flow changes, pump control is integrated with plant automation, operating hours are long or noise levels are a factor.
A Graco Husky AODD pump set up for drum transfer.
Prime supplies Graco Husky, ChemSafe and SaniForce AODD pumps – alongside Graco QUANTM EODD pumps.
Where compressed air is already available, Graco Husky pumps are a practical choice for straightforward transfer and process duties.
Graco QUANTM pumps fit processes that benefit from adjustable speed, automation and no reliance on compressed air. They also offer onboard speed adjustment and control options for integration with plant systems.
Comparing AODD and EODD pumps for a specific duty? Talk to Prime about which Graco diaphragm pump best fits your process.