ECO EFD Stepper Motor Dosing Pump: Specs, Turndown and How It Compares With Solenoid Models
"The EFD is a solenoid pump, right?" Plenty of people mix up EFD and DFD while browsing solenoid pump specs. One letter apart, both small square boxes. In fact the ECO series EFD is a stepper motor dosing pump. It works on a different principle and has a different adjustment range. If you're choosing a small dosing pump, it's worth looking at the two side by side.
What the ECO Series Is
The ECO series comes from the same manufacturer as NEWDOSE, and the panel carries the EVO name. As in any stepper motor dosing pump, the motor drives a PTFE diaphragm back and forth. The factory highlights precise adjustment, broad chemical compatibility from the PTFE diaphragm, a 100–240 V wide-range supply, the option of 24 V DC power, and resistance to air locking.
The standard pump head is PVC, with PVDF, PTFE and SS316 as options, much the same as the solenoid range. Each pump ships with 2 m of PVC suction tubing, 1.5 m of PE discharge tubing, an injection valve, a foot valve with strainer and fittings.
Stepper Motor Dosing Pump Specs: The Four EFD Models
The ECO selection manual lists only four stepper motor dosing pump models, all low flow:
- EFD-01-07: 1 L/h, 7 bar, 120 strokes per minute;
- EFD-03-07: 3 L/h, 7 bar, 240 strokes;
- EFD-06-05: 6 L/h, 5 bar, 240 strokes;
- EFD-09-03: 9 L/h, 3 bar, 240 strokes.
Shared specs across all four: adjustment range 0.05–100%, accuracy ±1%, tubing 4×6 mm, motor 15 W, weight 1.8 kg, supply AC 100–240 V 50 Hz or DC 24 V.
The model code reads like the solenoid range: the two middle numbers are flow and pressure, so EFD-06-05 means 6 L/h at 5 bar.
What does 0.05% actually mean? Scaled down, a 3 L/h pump at its lowest setting puts out only a milliliter or two per hour. Sites rarely go that low, but it shows how much room this stepper motor dosing pump has at the bottom end. It won't dose in jerky bursts the way a large pump turned right down does.
Choosing a stepper motor dosing pump among the four, look at pressure first and flow second. Say the injection point peaks at 4 bar and you need around 2 L/h. The EFD-03-07 leaves margin on both pressure and flow, which is steadier than running an EFD-06-05 near its limit. If you only need 0.5 L/h, the EFD-01-07 is enough.
Stepper Motor Dosing Pump vs Solenoid Pump Specs
Put it next to the NEWDOSE DFD-M solenoid pumps in the same flow band and the differences are clear.
Flow and pressure line up
The DFD-01-07-M is 1 L/h at 7 bar, the DFD-03-07-M is 3 L/h at 7 bar, the DFD-06-05-M is 6 L/h at 5 bar, and the DFD-09-03-M is 9 L/h at 3 bar. The four steps match the EFD almost one for one, so flow and pressure alone won't separate them.
Where they really differ
- Adjustment range: the EFD is rated 0.05–100%, good for very fine control. The solenoid pump adjusts by stroke rate, with a floor of 1 stroke per minute.
- Power and weight: EFD 15 W and 1.8 kg. DFD-M 30–40 W and 2.4 kg.
- Supply: the EFD runs directly on 24 V DC, handy at remote solar or battery-powered dosing points. The DFD standard supply is 220 V AC.
- Suction lift: the DFD-M is rated 3 m. The ECO manual gives no suction lift figure, so ask before mounting the pump above the tank.
When we build a spec sheet for solenoid pumps, we give the stepper models their own column and note the drive type. EFD and DFD differ by one letter. Get it wrong on a quote and the wrong pump arrives.
Where a Stepper Motor Dosing Pump Earns Its Place
Very small, steady, continuous doses suit a stepper motor dosing pump best. Think pilot rigs, antiscalant on small pure water units, or disinfectant on a building's secondary water supply. These jobs need anywhere from a fraction of a liter to a few liters per hour, the pump spends most of its time at low speed, and the wide turndown actually matters.
If the site only has DC power, the EFD should be near the top of the list. A 15 W draw is kinder to batteries and solar too, so the same battery lasts longer. On the other hand, if you need higher pressure, say above 10 bar, none of the four EFD models will reach it. Go back to the HX or X solenoid frames, or look at the newer Evodose models below.
Installation details matter. The standard tubing is only 4×6 mm, so keep the suction line short and avoid tight bends. Hold the foot valve a little off the tank floor so sediment stays put. For chemicals that gas off, like sodium hypochlorite, mount the pump below the tank level so the chemical floods the head. Fit the injection valve properly at the injection point so main line water can't flow back.
What Changed in the Newer Literature
In the 2026 NEWDOSE catalog, the stepper motor dosing pump range sits under the Evodose series and has grown. Besides the EFD manual model there are EP pulse, EM 4–20 mA and EC RS485 versions. Flow now runs from 9 L/h up to 100 L/h, with pressure up to 20 bar, a 25 W motor and 6×9 and 10×14 tubing. The low-flow manual models match the ECO manual at 15 W and 1.8 kg. The signal-controlled models at the same flows weigh 2.3 kg, worth knowing if space is tight.
The two documents disagree in places. The 1 L/h model's stroke rate is 120 in the ECO manual and 180 in the new catalog. The adjustment range is 0.05–100% in one and 1–100% in the other. Our advice: go by the factory's current literature and the nameplate when ordering, and ask directly if anything is unclear.
Conclusion
If you come across an EFD while comparing solenoid pump specs, remember it's a stepper motor dosing pump, not a solenoid one. The four ECO models cover 1–9 L/h at 3–7 bar, draw 15 W, can run on 24 V DC and offer a wide adjustment range. They suit tiny doses, tight accuracy needs and limited power supplies. For higher pressure, signal control or more flow, look at the newer Evodose models or NEWDOSE solenoid pumps, and confirm figures against the latest literature.
FAQ
Is a stepper motor dosing pump quieter than a solenoid pump?
The literature gives no noise data, so a direct comparison isn't possible. If noise matters on site, ask for a demo unit and listen first.
Can the EFD stepper motor dosing pump take a PLC signal?
The EFD in the ECO manual is manual only. The newer Evodose range has EP, EM and EC signal-controlled models, so choose one of those for PLC control.
Can the 4×6 mm tubing be replaced with rigid pipe?
Soft tubing is standard. If you need a rigid connection, check whether the factory has a matching adapter rather than modifying the ports.
Under what conditions is the ±1% accuracy rated?
It's the factory's stated figure and generally applies to steady conditions. In service, back pressure, suction lift and viscosity all have an effect, so calibrate once after installation.
Are spares shared with the solenoid pumps?
The head material options are similar, but the drive is different. Confirm diaphragm and head interchangeability by model, and keep a genuine spare diaphragm with the pump.
Not sure whether a stepper motor dosing pump or a solenoid pump suits your small dosing job? Send the dose, pressure and power supply through our contact page and we'll compare the specs with you.