Which power
The honest rule: buy petrol for the absent socket, not for the pressure.
Two questions decide this, and pressure is not one of them.
If yes, an electric machine is cheaper, quieter, starts instantly and needs no maintenance. The Kärcher K 7 WCM at 180 bar and 600 l/h cleans anything a house has.
If no — a paddock, a boatyard, a second property, a farm gate at the end of a track — petrol is the only answer, and that is the whole argument.
Petrol machines tolerate hours of continuous work. Domestic electric machines are designed for intermittent use, which is why the water-cooled motor on the top Kärcher exists.
Fumes — never indoors or in a garage, the exhaust is carbon monoxide. Maintenance. Noise. And a pressure level that will damage most of what a house is made of: at 221 to 234 bar, technique stops being a preference.
The BTGSHYNM at about 152 bar is the pressure of a good electric machine with no cable — which, for a large garden without power, is exactly the right specification.
Where electric covers almost everything and where noise and convenience decide the experience.
Where there is no socket and petrol is the only option.
Where the higher flow of petrol machines genuinely shortens the work.
Where petrol is never acceptable because of exhaust fumes.
| Your situation | The machine | The catch |
|---|---|---|
| Home with a socket | Electric | Limited by supply and cable |
| No mains power | Petrol | Noise, fumes and servicing |
| Large areas often | Petrol for flow | Weight and maintenance |
| Enclosed space | Electric only | Petrol fumes are dangerous |
Electric machines need frost protection and a clean inlet filter and little else. Petrol machines add everything an engine needs, and stale fuel left over a winter is the commonest reason a petrol machine will not start in spring.
Two different sets of risks.
234 bar working · 590 l/h · 5.9 hp four-stroke · 9 m (30 ft) hose
The only machine on this site that publishes a working pressure and a flow rate together.
Best for: Farmyards, contractors and large properties without power at the far end
2,200 PSI (≈ 152 bar) · 2.3 GPM · single-cylinder air-cooled
The most modest petrol machine here, and the only one listed on all six Amazon stores.
Best for: Large gardens and outbuildings without power, where 150 bar is plenty
180 bar · 600 l/h · 60 m (197 ft)²/h · water-cooled motor
The top of the domestic range, and the only one here whose motor is water-cooled — which is a statement about running time, not power.
Best for: Large areas cleaned in one session — long drives, farmyards, several vehicles — where the machine runs continuously rather than in bursts
241 bar max · 221 bar working · 5.9 hp 212 cc · 9.2 m (30 ft) hose
The rare petrol machine that publishes a working pressure as well as a maximum.
Best for: Yards, farm machinery, long concrete drives and any site with no electricity
Rarely. At that level you are cleaning concrete yards, farm machinery and stonework. The same pressure removes the surface of softwood decking, drives water behind render and strips paint. Domestic machines top out around 180 bar for a reason.
Oil changes on schedule, an air filter, a spark plug, and either fuel stabiliser or an empty tank over winter. That is genuinely more work than an electric machine — and it is why a petrol washer left in a shed for a year usually will not start when you want it.
Petrol machines typically offer more flow, which shortens large jobs. For domestic cleaning near a socket, that advantage rarely justifies the drawbacks.
No. Exhaust fumes contain carbon monoxide and are lethal in enclosed spaces. This applies even with the door partly open.
Loud enough to matter to neighbors and to make conversation difficult. In a terrace or a flat this alone often decides the choice.
Engine oil, air filter, spark plug and fuel management, on top of the pump care both types need.
Using an appropriate residual current device is strongly advised whenever water and mains electricity are combined outdoors.
Electric, comfortably. Cars need moderate pressure and good technique rather than the flow that petrol machines exist to provide.
Meant for: Farmyards, contractors and large properties without power at the far end
Where it is strongest: Working pressure AND flow rate published — the complete pair, which is rare anywhere
Where it is weakest: 234 bar is professional pressure with domestic consequences on soft surfaces
Meant for: Large gardens and outbuildings without power, where 150 bar is plenty
Where it is strongest: 152 bar is a pressure a domestic property can actually use
Where it is weakest: Petrol cost and maintenance for pressure an electric machine can nearly match
Meant for: Large areas cleaned in one session — long drives, farmyards, several vehicles — where the machine runs continuously rather than in bursts
Where it is strongest: Water-cooled motor: the specification that separates an occasional machine from one that runs for an hour
Where it is weakest: 180 bar will strip softwood, render and old paint if the nozzle is held close
Meant for: Yards, farm machinery, long concrete drives and any site with no electricity
Where it is strongest: Both pressures published: 241 bar maximum and 221 bar working
Where it is weakest: 221 bar will destroy softwood, render and old paint in seconds
$270 – $350
4 models
$430 – $660
4 models
Lances, nozzles and detergents from the same aisle, at the price we read. Confirm the fit against the machine you choose before ordering: it turns on the coupling and the part number, which the listing gives.
Comparisons we have already run between two washers from this guide or this aisle.
The washers above come from the catalog of this site. Specifications are those the manufacturer and the Amazon page publish; prices are what Keepa reported for the date below, and both move. The order follows declared specifications, stated strengths weighed against stated limits, and price. No machine here has been put to work by us, and nothing on this page pretends otherwise.
Last checked on
Prices quoted in these summaries are dated readings. The live price is shown next to each product.
Pressure washers and floor washers swing by a hundred dollars or more across the year, and the biggest "discounts" often land at prices the same model sold for six weeks earlier. UniverTrack tracks the real price history across retailers, spots fake reductions, and alerts you when it is genuinely the moment to buy.
