A pressure washer does not have a power setting. The nozzle is the setting. Swapping a red tip for a white one changes what the machine does more than the difference between two machines in the same price band, and it takes about a minute to learn.
The chart
| Color | Angle | Use it on | Never on |
|---|
| Red | 0° | Almost nothing. A single pencil jet for a specific stubborn spot on masonry, briefly | Wood, siding, cars, pavers, anything painted, people |
| Yellow | 15° | Stripping paint, heavy masonry grime, machinery | Wood, siding, cars |
| Green | 25° | Concrete, pavers, driveway edges, general hard-surface cleaning | Car paint, soft wood at close range |
| White | 40° | Siding, decking, fencing, cars, windows, final rinsing | Nothing much - this is the safe default |
| Black | 65° (low pressure) | Applying detergent. This is the only tip that draws soap | Rinsing - it has no cleaning force at all |
A wider angle spreads the same water over more area, so the force at any one point drops. That is the whole mechanism: you are trading intensity for coverage.
The two tips you will actually use
Green (25°) for concrete and hard surfaces, and white (40°) for everything else. If you only ever fit those two, you will clean your whole property safely and you will never damage anything.
The black soap tip is the third one that matters, and only because detergent will not come out without it — which is the single most common “my soap is not working” cause. See how soap injectors work.
Why the red tip is in the box at all
Honestly, mostly tradition. A zero-degree jet concentrates everything your machine has into a point, and on any surface softer than masonry it carves a line. It will cut skin. It etches concrete. It will punch through vinyl siding and strip paint off wood in a single pass.
The legitimate use is a specific stubborn spot — a patch of tar, a bolt head — on masonry, held moving, briefly. For broad stubborn concrete the right tool is a turbo nozzle, which gives zero-degree intensity with 25-degree coverage. Many people never fit the red tip, and that is a reasonable decision.
The flow rating nobody mentions
Every nozzle has an orifice size matched to a flow rate, and it is usually printed on the tip or the packaging as a GPM figure or an orifice number.
Fit a tip sized for 2.5 GPM to a 1.2 GPM machine and the orifice is too large: water passes through without building pressure, so you lose force. Fit a tip sized for 1.2 GPM to a 2.5 GPM machine and you over-pressure the pump. Buy a set whose stated rating is close to your machine’s GPM — which is on the machine’s label.
This is why cheap generic sets sometimes disappoint on low-flow electrics: the set was rated for a gas machine. The nozzle set picks are grouped by rating for exactly this reason.
Distance matters as much as color
A white 40-degree tip two inches from vinyl siding is more aggressive than a green tip two feet away. Pressure falls off quickly with distance, which means distance is your fine adjustment between the five coarse settings the colors give you.
The habit worth building: start further away than feels necessary, move in until it is cleaning, then stop. For the surface-by-surface limits see what PSI pressure washer do I need and surfaces you should never pressure wash.
Practical habits
Release the trigger before swapping tips, and pull the collar fully so the tip clicks home — a half-seated tip fires out under pressure. Keep the tips in a holder; a five-piece set with no holder becomes a two-piece set by August. And carry a thin wire to clear a blocked orifice from the back, never by forcing anything in the front.
