A procurement manager comparing quotations for commercial steam cleaning equipment will usually receive two very different proposals: one based on a stationary unit plumbed into an existing water and power supply, and another based on a battery-powered machine that can be driven or pushed to the work. The prices look different, the specifications look different, and the operating routines they create are completely different. The comparison below follows the way buyers actually work — site survey first, then equipment class, then verifiable specifications, then lifetime cost — so that a fixed unit and a mobile unit can be judged on the same terms.
Start with the site survey, not the machine
Before any model shortlist makes sense, write down four facts about the location where the cleaning will actually happen.
- Water supply. Is there a tap within hose reach, and is it clean tap water? A fixed unit expects a continuous inlet; a mobile unit carries its own tank.
- Electrical supply. What voltage and what outlet capacity are available at the cleaning point, and how far is the nearest supply from the farthest vehicle or surface being cleaned?
- Floor and access conditions. Sloped parking ramps, tight garage columns, drainage gullies and wet floors all change what a wheeled machine can physically reach in a shift.
- Work pattern. Is the workload one fixed bay serving a steady queue of vehicles, or several dispersed areas — engine bays, interior trim, hard floors — handled by a small team moving around?
This survey determines which class of machine is being compared. A quotation that ignores it cannot be compared at all, because the same steam technology produces opposite running costs depending on whether the operator walks 30 metres per vehicle or does not move at all.
How the two classes differ in construction and in practice
Fixed units. A fixed steam cleaning machine such as the PowerDe HW02 is a stationary, high-output machine designed around a permanent service point. The published detail-page parameters for the PowerDe HW02 (220V) give a 6 kW heater, a steam temperature of 160° and a vapor pressure of 0.8 MPa, an 80 L tank made of SUS304 stainless steel, and overall dimensions of 1,200 × 800 × 1,200 mm including handles. It takes tap water through a 4-point internal-tooth joint (1/2 inch), switches between dry steam and wet steam, and can be paired with a vacuum cleaner. The product page places it in vehicle exterior cleaning at gas stations and parking lots, interior vacuuming and disinfection, and engine-compartment cleaning, and it lists leakage, short-circuit, high-temperature, high-voltage, water-shortage and high-voltage-explosion protection.
The practical advantages follow from that construction: a large stainless tank and a mains supply mean the machine is not limited by battery capacity, the heater runs continuously through a long queue, and one strong service point can serve a busy bay. The trade-off is immobility — the reach of the job is the reach of the hoses, and the unit needs a prepared position with water and power.
Mobile units. The battery-powered end of the range is built around the same dry-steam, wet-steam and hot-water functions, but on a chassis that moves to the vehicle instead of pulling the vehicle to the machine. The PowerDe PWD02, PWD01 and HMW2 are driving-style machines listed for indoor garages and narrow outdoor parking spaces, and each model is offered both with and without a battery. The battery variants on this site mention leakage, short-circuit, high-temperature, high-voltage and water-shortage protection. Pushed models such as the PowerDe HMW3 are high-temperature, high-pressure machines with dry- and wet-steam modes, listed for cleaning and disinfecting hospital beds and medical machinery, and shown with hand-push movement, a 4.5 kW PTC semiconductor heater, a 50 L clean-water tank and a 48 V battery working supply.
Mobile machines win where the surfaces are dispersed: several bays, several floors, or cleaning that shares a workforce with other duties. They also suit sites where no suitable water or power point exists at the cleaning location. Their limits are tank and battery capacity, which is precisely why the same model is sold in battery and non-battery versions and why the shift plan has to allow for refilling and recharging.
Compare only specifications you can verify
Sales sheets use similar words — "high pressure", "high temperature", "heavy duty" — for very different machines. Insist on numbers, and record them in the same columns for every quotation. The comparison sheet used inside PowerDe should be able to answer the following questions for both classes.
| Comparison item | What to ask a fixed unit | What to ask a mobile unit |
|---|---|---|
| Heater output (kW) | Rated heating power and the supply it needs — the HW02 is listed at 6 kW on 220 V | Rated heating power and how long the heater can run on the battery — the HMW3 is listed at 4.5 kW with a 48 V working supply |
| Steam temperature and pressure | Both values, measured at the nozzle — the HW02 lists 160° and 0.8 MPa | Both values; if the page does not publish them, request them in writing |
| Tank volume and material | Tank size and whether it is stainless steel (HW02: 80 L, SUS304), plus whether the water inlet is continuous | Clean-water tank size (HMW3: 50 L) and how many vehicles it covers between fills |
| Power source and downtime | Required socket capacity and cable length to the farthest bay | Battery capacity, run time per charge and charger output — these decide whether one machine covers a shift |
| Modes offered | Dry steam, wet steam, and whether a vacuum function is available | Dry steam, wet steam and hot water, and which modes can run at the same time |
| Protection functions | Ask for the full list — the HW02 page names leakage, short-circuit, high-temperature, high-voltage, water-shortage and high-voltage-explosion protection | Ask for the full list and how each protection behaves on a wet floor in a public car park |
| Footprint and access | Dimensions and where the unit will sit permanently (HW02: 1,200 × 800 × 1,200 mm including handles) | Wheel type, whether it is driven or hand-pushed, and whether it clears ramps and speed bumps |
| Battery inclusion | Not applicable | Confirm whether the quotation includes the battery; PWD01, PWD02 and HMW2 are listed both with and without it |
One detail on that last line is worth more attention than it looks. Mobile models on this site are catalogued as separate listings with and without a battery, so two quotations can appear to be for the same machine at very different prices while actually quoting different configurations. Confirm the battery line item before comparing anything else.
Match the class to the job, bay by bay
Operators who compare these machines after a season of use usually describe the decision as a question of workload density rather than power. A fixed machine pays for itself where the same bay handles a continuous flow — the site material puts fixed units at gas stations and parking lots, where one prepared point with mains water and 220 V power can run through a queue without waiting on a charge. The 80 L stainless tank and continuous tap inlet matter most in exactly that pattern.
A mobile machine earns its place where the surfaces are scattered. A driving-style unit covers narrow garages and dispersed parking spaces without dragging hoses across a public area, and the same crew can move between exterior panels, an engine compartment and a hard floor in one pass. Where the work includes disinfecting shared equipment in a clinical setting, a pushed machine is the practical form; PowerDe lists the HMW3 for hospital beds and medical machinery, which is a different procurement route from vehicle cleaning and should be quoted as a separate requirement.
Many sites end up with one of each: a fixed unit anchoring the main bay and a battery machine covering overflow, detailing and remote surfaces. If that is the plan, ask the supplier to quote both from the cleaning equipment series with one shared set of consumables and accessories, so that spare nozzles, hoses and service visits are not duplicated across two suppliers.
Total cost of ownership: the columns most buyers leave out
Purchase price is the smallest column in a two-year comparison. Add these before signing.
- Installation. A fixed unit needs a water point, a suitable 220 V supply and a permanent position with drainage. Price those works, not just the machine.
- Energy and water. Compare rated heating power against the hours the machine will actually run, and compare tank-based water use against a continuous inlet.
- Battery and consumables. For mobile units, price the battery (or confirm it is excluded), the charger, and the replacement interval quoted by the manufacturer.
- Downtime. A fixed unit is limited by plumbing and heating faults; a mobile unit also loses any shift in which the battery was not charged. Ask what spare provision and service response the supplier offers for each class.
- Service access. Confirm response time, parts availability, and whether the distributor servicing your site is the one handling that equipment class.
- Training. Dry steam, wet steam and hot water each need different nozzle technique on paint, trim and engine parts. Ask what training comes with the machine and what it costs to repeat.
Questions that settle the choice with the manufacturer
A supplier that builds its own equipment can answer these directly, and the answers are usually more useful than any brochure.
- Which model do you recommend for my layout, and which two models would you not recommend — and why?
- Which specification values on my quotation are published on your product page, and which are quoted verbally?
- For a mobile unit, what is the real run time per charge with the heater on, and what does a spare battery cost?
- For a fixed unit, what site preparation do you expect from us, and what do you supply?
- If my volumes grow, can a fixed bay and a mobile unit be combined under one service contract?
- If our requirement is not in your catalogue, what does customization involve and how long does it take? PowerDe lists engineering services and customized steam cleaning equipment for exactly this case.
Run both machines on the same site before ordering
Fixed and mobile machines are not two grades of the same product; they are two different answers to where the water, the power and the operator should be. Fixed equipment buys continuous output and larger tanks at one prepared point. Mobile equipment buys reach and shared use of a crew. Write the site survey, demand published numbers on temperature, pressure, heater output, tank volume and run time, and price installation, batteries and service alongside the purchase price — and the two quotations become comparable.
Shenzhen PowerDe Automation Precision Equipment has built automation and precision equipment since 2007 and supplies its cleaning range in fixed, driving-style and hand-pushed forms. Send your site survey — layout, available water and power, workload and shift pattern — to the engineering team at PowerDe, and you will receive a configuration proposal that names the equipment class for each bay rather than a single generic quotation.
