A specification table that lists "wet steam" next to "dry steam" looks like a complete answer until a buyer has to compare two quotations and discovers that neither supplier explains what the difference does to the job. Wet steam is not a marketing label. It is the higher-water version of the output, and the practical reason it exists is that water volume, not temperature alone, is what carries loosened soil off a surface. Before you sign for a machine because its page says dry and wet steam, here is how to check what the published figures actually support and what you can measure yourself.
Read the whole specification block, not the mode list
Start by writing down every figure printed on the product page for the model you are quoting. For the fixed unit in the PowerDe cleaning range, the Fixed Steam Cleaning Machine PowerDe HW02 page states 220 V working voltage, 6 kW heating power, 160 degrees steam temperature, 0.8 MPa vapour pressure, an 80 L tank in SUS304, a footprint of 1,200 by 800 by 1,200 mm including handles, a tap-water inlet with a 4-point internal-tooth joint in 1/2 inch, dry and wet steam output plus a vacuum function. Treat that list as the manufacturer's declaration.
Then note what the same page does not state, because the omissions are where buying mistakes happen. Mode selection, tank material and heating power are published. Water consumption per hour in each mode, nozzle diameters and spray angles, hose and wand lengths, heat-up time from cold, and continuous run time at rated pressure are not on that page. Those are exactly the figures that separate a good wet-steam machine from a poor one.
The same pattern appears on the hand-pushed model in the range. Its page publishes machine dimensions of L1150 by W520 by H1030 mm, hand-push movement, a 4.5 kW PTC semiconductor heater, a 50 L clean-water tank, a tap-water inlet, dry and wet steam modes, 48 V battery working supply, and a high-pressure water gun with a nozzle. Steam temperature, steam pressure, battery capacity, run time, charger output, weight, accessory list and noise level are not stated there. Ask about each missing item in writing, and accept either a number or an explicit "not specified".
Ask for the figures that define wet steam
Dry steam produces little visible moisture and works by heat on the surface. Wet steam carries more free water, which is what flushes dissolved grease and suspended soil away rather than leaving it to be wiped off. When you evaluate commercial steam cleaning equipment for rinse-sensitive work, request these items per mode:
- Water delivered per hour in wet mode and in dry mode. Two machines can both claim 0.8 MPa and behave very differently once the trigger is held open for a full shift.
- Nozzle options, with orifice size and spray pattern for each, plus whether the wet mode uses a different nozzle than the dry mode.
- Whether steam temperature and pressure are measured inside the boiler or at the nozzle outlet, and how long the machine holds rated output before the tank needs a refill.
- The refilling rule during operation: whether the tank can be topped up mid-job, and whether the inlet pressure from your tap is enough to fill it at the rate the machine consumes water.
- How the mode is selected, whether one operator can change it with gloves on, and how long the changeover takes.
- The protection functions named on the page, written out as a list rather than a sentence. The fixed model's page describes leakage, short-circuit, high-temperature, high-voltage and water-shortage protection.
Request the answers in an email or a stamped document, not a phone call. A supplier who sends dated figures has a specification to stand behind. A supplier who quotes a higher number verbally than the one printed on their page is telling you the published figure is a target.
Check the mode against the job, not against the datasheet
Mode names are only useful once you match them to your dirt and your surface. Work through your own tasks and decide which output each one needs:
- Heavy grease on a surface with a drainage path. Wet steam does the flushing; dry steam mainly heats the grease loose first.
- Heavy grease on a surface with no drainage path, or an area where free water is a hazard. Dry steam plus wipe-off, with recovery of the wiped soil.
- Surfaces where electrical equipment, insulation or bearings must stay dry, where free water is the reason a mode is unacceptable.
- Interior vehicle work, where the page for the fixed model lists exterior cleaning at petrol stations and parking areas, interior vacuuming and disinfection, and engine-compartment cleaning as the published uses.
- Cleaning and disinfecting hospital beds and medical machinery, which is the use the hand-pushed model's listing describes.
Do not assume that a machine bought for one of those published uses is automatically suitable for another. Where your application is outside what the product page states, raise it before ordering through the manufacturer's customized steam cleaning equipment service, so the mode, nozzle set and tank size are agreed while the configuration is still open.
Measure what you can at your own site
A buyer does not need a laboratory to test the main claims. The checks below need a stopwatch, a metered water source, an infrared thermometer, a socket voltage reading and a marked container:
- Log the voltage at the socket under load and compare it with the published working voltage. A 6 kW machine on a weak circuit heats more slowly and holds less pressure.
- Time the heat-up from cold, with the ambient temperature written beside the result. Compare that time with what the supplier states in writing.
- Record the pressure gauge at the start of a job, in the middle, and immediately before the low-water cut-off. A reading that slides as the tank empties tells you how much of a shift runs at rated pressure.
- Run each mode for a fixed period into a marked container and read the collected water. The difference between the two numbers is the practical meaning of wet steam versus dry steam.
- Take an infrared reading at the nozzle outlet and separately on the surface being cleaned. The nozzle reading is the one relevant to cleaning performance.
- Trigger the water-shortage cut-off deliberately and confirm the machine responds as the manual says. Keep a signed record of what you observed.
- Measure the operating footprint including handles against the published dimensions before the unit is committed to a bay, a garage or a service van.
Run the same test on a surface you know well, with the soil level you deal with daily. Judge the result by whether the soil is gone and how much wiping and recovery the operator still has to do, not by how impressive the plume of steam looks.
Turn the verified figures into order terms
Anything you confirmed becomes a contract line: model code and shipping variant, working voltage or battery supply, heating power, steam temperature with its measurement point, vapour pressure, tank volume and material, water consumption per hour by mode, the nozzle and accessory list actually shipped, hose and wand lengths, the protection function list, and the footprint. Attach the manual revision and the spare-parts list to the order and name the datasheet version you reviewed, because product pages get updated and a version number is what protects you afterwards.
For repeat or multi-unit purchases, ask for a written statement that delivered units match that version. For any figure the supplier cannot give, decide before ordering whether you can live without it. If the missing figure is the one your acceptance test depends on, treat it as an unresolved commercial risk and keep the enquiry open rather than substituting an assumption.
Published specifications are the starting point of a purchase, not the end of one. The page tells you what the machine claims. Documents, measurements at your own site and order terms tell you what it delivers, and wet-steam performance in particular only becomes a number when you measure the water.
To confirm a specific figure for a specific model, or to discuss a configuration outside the published range, contact Shenzhen PowerDe Automation Precision Equipment Co., Ltd. at sales@powerde.net or +86 13023198376.
