1. How does the machine get from one job to the next?
"Mobile" covers several very different designs. PowerDe's cleaning range splits into three: self-propelled driving-style units, hand-pushed units, and fixed stationary units. The mobile steam cleaning machine models in the driving-style series — PWD01, PWD02 and HMW2 — are built for indoor garages and narrow outdoor parking spaces, where an operator can ride or walk the machine between vehicles instead of dragging it. The hand-pushed HMW3 is listed at 1,150 × 520 × 1,030 mm, a footprint that still clears standard doorways and service corridors.
Ask the supplier which of these three forms fits your site, and give them the actual constraints: doorway widths, ramp gradients, step heights, the turning circle in your bay, and the distance between the parking rows and the water point. A unit that has to be carried over a kerb every two cars will not be used.
2. Battery or corded — and what does that change on the floor?
The PWD and HMW2 models are each listed in two variants: with battery and without battery. The HMW3 runs on a 48 V battery. That single option decides your working radius, so it deserves a direct question. A battery-powered unit can move along a row of vehicles without an extension cable and can work where no supply exists — a curbside bay, a rented corner of a lot, a farm yard. A mains unit needs a suitably rated outlet within cable reach and a safe cable route across a wet floor.
Then ask what is not printed on the page. Battery capacity and run time, charger output and recharge time, machine weight, and hose and wand lengths are not published on these product pages. Get them quoted as numbers, along with the warranty term and the price and lead time for a replacement pack. A battery that dies halfway through a Saturday queue is a capacity problem, not a machine problem.
3. Which modes does it actually run?
The driving-style models — PWD01, PWD02 and HMW2 — are described as active-water machines with dry steam, wet steam and hot water modes. The hand-pushed HMW3 offers dry and wet steam. The stationary HW02 adds a vacuum function alongside its dry and wet steam modes.
This matters because steam and hot water are different tools. Steam carries heat into a surface with comparatively little water, which suits engine bays, interiors, and surfaces where runoff has to be minimal. Hot water delivers volume and impact, which suits bodywork and hardstanding. If your work mixes both, a machine that switches between modes on one platform saves you buying twice. If you only wash exterior panels, extra modes are cost you will never recover.
4. Where does the water come from, and where does it go?
Check the inlet. The HMW3 takes tap water through a 4-point internal-tooth fitting and carries a 50 L tank; the stationary HW02 uses an 80 L SUS304 tank with the same style of tap-water connection. Ask two things: whether your water source matches the fitting without an improvised adapter, and whether the tank size means one fill or three per shift. A small tank on a busy site is a hidden operating cost, because every refill is operator time.
Then ask where the runoff goes. Steam cleaning cuts water use compared with hose washing, but the liquid still falls to the ground carrying oil, grease and detergent residue. In an indoor garage, a parking lot or a food-handling area, that usually means a drain, an interceptor or a documented collection method — and in many jurisdictions a permit condition attached to it. Confirm what your own site requires before the machine arrives; that is your obligation, not the supplier's.
5. What are the real limits of the steam itself?
The published figures for the stationary HW02 are 160° steam temperature, 0.8 MPa vapor pressure and 6 kW heating power, running on a 220 V supply. Ask the same three numbers — temperature, pressure, heating power — for any model you are quoted, plus the recovery time between triggers and the flow at the gun rather than at the boiler. Those numbers together tell you how fast the machine works and how much chemical you can stop buying.
Note what is missing, too. Steam temperature and pressure are not published for the HMW3, and the same gap applies to some other listings. Do not assume a mobile unit matches a stationary one, and do not let a sales conversation fill the gap by inference. If a specification is not on the page, ask for it in writing or treat it as unknown.
6. Power supply and protection
High-temperature, high-pressure equipment in a wet environment is an electrical safety question first. The HW02 works on 220 V. The HMW3 works on a 48 V battery. The PWD02 and HMW2 listings mention leakage, short-circuit, high-temperature, high-voltage and water-shortage protection; the HW02 overview adds high-voltage explosion protection to that list, and because the item count differs between pages, ask for the full protection set for your specific model and configuration rather than relying on a number quoted in marketing copy.
Match the answer to your installation: circuit capacity, earthing, RCD or GFCI protection, and the route for cables away from standing water. On a 220 V machine, verify what your local supply requires before commissioning.
7. Service life, consumables and support
Ask what wears out and what it costs. Heaters scale up in hard-water areas, seals and hoses age, nozzles foul, and batteries lose capacity on a schedule you cannot negotiate with. Request the consumables list, the service interval, and the price and shipping lead time for spare parts. Shenzhen PowerDe Automation Precision Equipment lists equipment customization and technical support among its services, so it is reasonable to ask directly about configuration for your site and about the support channel you will actually use at 7 a.m. when the machine will not fire.
Also ask what is in the box. Accessory lists are not published on these pages, and a machine sold without the brush, extension wand or interior tool you need will arrive half-finished.
8. Match the machine to the job, not the brochure
PowerDe also makes semiconductor and thin-film production equipment alongside its cleaning range, which is why a spec sheet alone can be misleading. Ask the vendor to confirm that the model you are quoting is intended for your use case — vehicle exterior and interior cleaning, engine compartments, or facility cleaning — and to put the applicable applications in the quotation. For vehicle work, the HW02 fixed steam cleaning machine page describes exterior cleaning at fuel stations and parking lots, interior vacuuming and disinfection, and engine-compartment cleaning. Scenario terms that appear in a keyword list or a sales email are not a product claim until the manufacturer confirms them for your model.
9. Total cost over the life of the machine
Compare quotations on landed cost, not list price: machine plus battery if required, freight and import handling, fitting or drainage work, consumables for the first year, and the operator time the machine saves or adds. A mobile unit that avoids cable runs can pay for a more expensive power train. A stationary unit with a larger tank can beat a smaller mobile one on a fixed site with a water connection and a queue of vehicles to process.
Before you sign
A short list to settle in writing: mobility type and dimensions against your site; battery or mains with stated run time; modes you will actually use; tank size and inlet fitting against your water supply; temperature, pressure and power; the protection package for your configuration; consumables, service interval and parts lead time; accessories included; and the applications the manufacturer will stand behind for that model. Contact PowerDe with your site measurements and duty cycle, and ask them to match a model to both — the specification gaps above are exactly the questions a buyer should be getting answered before payment.
