1. What exactly is being cleaned, and how dirty is it?
Ask the operator to name the job, not the machine. Exterior vehicle surfaces, interior carpets and seats, engine compartments, floor grease, and bin-store disinfection all put different demands on the equipment. A surface wash is mostly about water volume and drying. An engine bay needs heat and pressure to release baked-on oil, which is why a parking lot vehicle cleaning equipment spec is usually read for its steam temperature and vapor pressure before anything else. Floor grease in an indoor level is a third problem again, because the soil is on a horizontal surface and the run-off has to be contained.
Ask for the soil level as well. Traffic film, pollen, and light dust are a different workload from oil residue and winter salt. Vendors quote confidently when the soil description is vague, and the shortfall appears later as long cycle times.
2. What utilities can the site actually supply?
This single question eliminates more unsuitable options than any other. Confirm the supply voltage at the intended location, whether a water connection and drain are within hose range, and whether the site has the electrical capacity for a heating element rated in the 6 kW class. A fixed unit such as the PowerDe HW02 runs on 220 V with a 6 kW heating element, an 80 L stainless steel tank, steam at 160° and 0.8 MPa vapor pressure. Those figures decide placement long before the purchase order.
Battery-powered options exist for sites where the cable run is the problem. The driving style steam cleaner units are built for indoor garages and narrow outdoor parking spaces, and the catalogue lists each model with and without a battery. Compare the version that matches your shift length, not the one with the longest specification line.
3. Who operates the machine, and how long is the shift?
Staff-run cleaning and driver-operated cleaning need different designs. Ask how many machines run per shift, how many staff touch the unit, and whether the operator drives the equipment between bays or pushes it. Hand-pushed units suit tight areas and single-vehicle tasks. Riding units suit long rows of bays where walking distance between vehicles adds up over a day.
Then ask about training. A machine with several modes requires a written sequence for which mode to use on which surface. Ask the vendor what documentation ships with the unit and what the training actually covers.
4. What are the safety protections and the service terms?
Steam at high temperature and pressure in a public area is a supervision risk, not just a purchasing decision. Ask which protections the machine includes. PowerDe's product pages list leakage, short-circuit, high-temperature, high-voltage, and water-shortage protection on several models. Get the list in writing for the specific model you are buying, because the wording differs across the catalogue.
Then put the service terms into the comparison sheet: which parts are consumables, what a spare nozzle and hose cost, how quickly parts ship, and who performs the warranty work in your region. Two machines at the same price can be several thousand apart once the first two years of parts and downtime are counted.
5. What does a day of operation cost?
Ask the vendor to walk through a typical day rather than to state a rating. Heat-up time between vehicles, tank capacity against the number of vehicles per hour, and water consumption all belong in the arithmetic. Steam-based cleaning works with far less water than a continuous hose wash, which matters where water discharge is regulated or metered. Get the figures for your own cycle, because a specification measured in a test bay will not match a Saturday queue.
Add labour. The unit that washes an interior in one pass instead of two is worth a higher purchase price if it removes half an hour of handwork per shift.
6. What will you do with the answer?
Send the same question set to every bidder and require responses in the same format. A comparison sheet that mixes a brochure claim with a written answer is not a comparison. Once the answers are in the same column, the differences become obvious: one bidder addresses your voltage, another avoids the service question, and a third prices a variant you did not ask for.
If you want a written answer against your own site conditions, Shenzhen PowerDe Automation Precision Equipment works on customized configurations for cleaning operations, and enquiries go through the customized steam cleaning equipment page.
