Yacht exteriors are a difficult cleaning brief. The hull combines gelcoat, antifouling coating, stainless fittings, teak or composite decking and often an underwater skin that carries hardened salt, algae and fuel film. A buyer evaluating a steam cleaner for yacht exterior surfaces is not choosing between brands from a brochure; they are deciding whether one machine can handle marine soiling without damaging coatings, and whether it survives a wet, salty working environment. The checklist below is how a purchasing team should assess the equipment before requesting a quotation.
Start With the Soil, Not the Machine
Marine deposits fall into three groups, and each responds differently to heat and pressure. Salt crust and loose algae come off with warm water and mechanical action. Fuel film, oily streaks along the boot stripe, and grease around through-hull fittings need heat to loosen, which is where a commercial steam cleaner earns its place. Bonded scale on waterline surfaces and around through-deck hardware usually needs dwell time, not more pressure.
Ask the supplier what their machine is actually built for. PowerDe's cleaning-equipment line is documented around dry steam, wet steam and hot water modes, with a fixed 220 V unit rated at 6 kW heating power, 160° steam temperature and 0.8 MPa vapour pressure feeding an 80 L stainless tank. Those figures give you something concrete to compare with your workload, rather than a marketing adjective. If a supplier cannot publish temperature, pressure and tank capacity, you are buying on trust.
Pressure and Temperature: Match Them to the Substrate
Heat and pressure are separate controls, and a marine job needs them to be adjustable independently. Gelcoat, antifouling paint and anodes can be etched or stripped by a narrow high-pressure jet held too close, whatever the water temperature. Deck seams, bedding compound and portlight seals can be forced open by pressure that would be harmless on a steel hull.
So the practical questions to put to any vendor are: what is the working pressure at the nozzle, not just at the pump; which nozzle set comes with the machine; is there a fan or wide-angle tip for coatings and a concentrated tip for metal fittings; and can the operator switch between a steam-dominant mode for grease and a hot-water mode for rinsing without stopping the job. A machine that offers dry steam, wet steam and hot water in one unit covers more of the yard's work than a single-mode steamer, and it reduces the number of machines on the dock.
Construction and Corrosion Protection
A pressure washer that works afloat lives in the harshest environment it will ever see. Check what the tank, frame and heater assembly are made of. PowerDe's 220 V fixed unit specifies an 80 L SUS304 tank and a 4.5 kW PTC semiconductor heater on the hand-pushed model, which is the kind of material specification you want in writing. Ask the same of any candidate: stainless or aluminium frame, corrosion-resistant fittings, sealed electrical components, and a documented protection set. PowerDe lists leakage, short-circuit, high-temperature and water-shortage protection on its machine pages, which matters more near water than it does in a garage.
Then check the power reality on your site. Fixed units run on 220 V mains. Mobile units in the same range — the driving-style and hand-pushed models — run on battery, which is the difference between cleaning a pontoon or a raft where no shore power is available and losing an hour pulling a cable.
Mobility and Water Supply on the Dock
Yard layouts punish equipment designed for a workshop floor. Consider how the machine moves from the quay to the berth, whether it rolls over grating and uneven decking, and how much of its own water it carries. A self-contained tank lets the operator work away from a tap; a machine that depends on a mains water inlet needs the hose run planned in advance. PowerDe's mobile units are built for confined spaces such as garages and tight parking bays, which is a fair proxy for a narrow side deck, but you should confirm the footprint, hose and wand lengths against your own gangway before ordering — those figures are not published on every product page.
Water Use, Runoff and Compliance
Steam-based cleaning uses far less water than hose washing, and that is a real operational advantage: less runoff to contain, less standing water on the deck, faster turnaround between vessels. It also supports a lower-detergent workflow, which matters where the marina restricts discharge or where antifouling residue in the runoff has to be captured.
Do not let a supplier sell you compliance you have to verify yourself. Ask what the local marina or harbour authority requires for collection and disposal, and write that into the method statement you give your crew. The machine changes the water volume; your procedure still governs the runoff.
What to Test Before You Buy
Insist on a live demonstration on your own surfaces, and score it against a short list: can the operator remove fuel film from gelcoat without visible etching; does the steam lift grease around a propeller shaft and through-hull fitting without solvent; how long can the unit run before it needs refilling or reheating; how long does reheating take; and how many people are needed to move and operate it. Compare the answer across at least two machines on the same panel.
Also ask what the demonstration machine is not telling you. Published pages describe applications such as vehicle exteriors, interiors and engine compartments; marine use is a market PowerDe lists keywords for, but the specific duty cycle on a hull is something you should confirm directly with the manufacturer and put in writing in the order.
Service, Spares and Total Cost
Downtime is the hidden cost in cleaning equipment. Price the machine together with the consumables that wear out — nozzles, seals, hoses, heating elements — and ask how they are supplied and how fast. Confirm warranty terms for a unit used outdoors in salt air, since many warranties treat corrosive environments differently. A supplier with in-house R&D, manufacturing and testing capability, as PowerDe presents itself, should be able to answer those questions directly rather than routing them to a reseller.
The Decision in Short
Buy on the numbers, the corrosion protection and the demonstration — not on the claim. A suitable machine for yacht exterior work gives you independently controlled heat and pressure, multiple cleaning modes, a corrosion-resistant build, a power and mobility configuration that fits your berth, and published specifications you can check line by line. Send your surface types, typical soiling and dock layout to the supplier, and ask them to map their range to that brief. That single step separates a machine that works on a hull from one that only looks capable on a datasheet.
