HydroHub™ A-900 PEM Engine Enhancement System
The A-900 is the unit most single-vehicle owners end up with. It suits 2.7 – 7.0 L petrol and diesel engines — a 4WD wagon, a dual-cab ute, a light truck or a large-displacement campervan engine — and produces 900 ml/min of hydrogen-oxygen gas from purified water while the engine runs. Highest-output unit in the compact range, it mounts in the engine bay or behind the cab, runs off the existing 12 or 24 V supply, and comes off again without a trace: nothing is cut, and the fuel system and ECU are untouched.
Suitable for diesel 4×4 fleet vehicles, compatible with mining and off-road transport, and ideal for utes, vans, and 4WD fleet vehicles.
- Displacement
- 2.7 – 7.0 L
- Output
- 900 ml/min
- Voltage
- 12 – 24 V DC
- Power draw
- 170 W · 20 A
Hardware-only supply. Installation is performed by your own qualified technician — see the installation guide.
Full specification
| Rated engine displacement | 2.7 – 7.0 L |
|---|---|
| Mixed H₂/O₂ output | 900 ml/min |
| Voltage | 12 – 24 V DC |
| Current / power | 20 A · 170 W |
| Water tank | 1.0 L |
| Water quality | Deionised / purified, TDS ≤ 5 µS/cm |
| Dimensions | 230 × 184 × 280 mm |
| Net weight | 8.1 kg |
| Outlet line | 8 mm OD |
| Fuel compatibility | Gasoline · Diesel · LPG · Hybrid |
Engineering features
- Pure-water PEM stack — no KOH / NaOH caustic electrolyte
- No corrosive carry-over into the engine air path
- Instant gas production — no onboard hydrogen storage
- Introduces hydrogen-oxygen mixed gas upstream of combustion via the engine air intake
- Non-destructive and reversible installation
- Automatic water refill and drainage circuit
- Water-shortage alarm
- High-TDS alarm
- Over-temperature shutdown
- Vibration-sensor automatic start / stop — runs only while engine runs
- Adjustable vibration sensitivity
- Deionized / purified water requirement: TDS ≤ 5 µS/cm
Applications
- 4WD & light trucks 2.7 – 7.0 L
- Medium-duty commercial
- Small diesel generator sets
- Mining support vehicles
These are combustion-enhancement devices. No emissions-compliance or fuel-saving guarantee is expressed or implied. Professional installation and controlled field evaluation are recommended.
Technical background
This unit uses PEM/SPE (solid-polymer) electrolysis of deionised water, with no potassium hydroxide electrolyte. The references below describe the electrolysis architecture, the combustion mechanisms involved and the published evidence, including studies that report no measurable benefit.
- PEM vs alkaline electrolysisSolid-polymer, pure-water cells compared with KOH electrolyte cells.
- hydrogen combustion enhancement principlesFlame speed, ignition delay and the conditional nature of reported efficiency effects.
- engine applications for PEM/SPE oxyhydrogenDiesel engines, generator sets, furnaces, fixed industrial and marine engines.
- 2026 Scientific Reports HHO study reviewWhat the HG80 alkaline experiment tested, and what it does not establish.
Combustion Enhancement provides the technical evidence and PEM/SPE oxyhydrogen research. Hydrogen Machines supplies the commercial PEM/SPE systems.