The FlowPro Solutions remote control downstream system lets you control your chemical draw right from where you're working — no walking back to the rig mid-job. We install this system on our Ultimate Mini pressure washing skid, and we can add it to just about any build we do — skids, trailers, or van setups. We also carry the complete Gen 5 FlowPro Remote Control Downstream System right here in our store.
Watch the full step-by-step walkthrough below — we cover the entire setup and operation in the video, then use this article as your quick reference for the rules that matter most.
How Downstreaming Works
Downstreaming uses your pressure washer's volume to apply a small dilution of soft wash solution. As water flows through the injector, it creates a vacuum (the venturi effect) that pulls chemical into the stream — but only when pressure at the nozzle is low. That's why your nozzle choice makes or breaks the whole system. For the full breakdown of injectors, check valves, and nozzle sizing, read our guide: Downstreaming with a Pressure Washer: The Complete Guide.
Setup: Get This Right or It Won't Pull
The video above walks through the setup step by step. Whatever you do, don't skip these two rules — the injector will not pull if you're running the wrong injector for your machine or the wrong nozzle at the gun:
- Match the injector to your machine's flow. An injector rated well below or above your pressure washer's GPM won't draw correctly. Our downstream calculator picks the injector size, nozzle and bleach mix from your GPM and hose length.
- Use a large-orifice soap nozzle. The injector only pulls under low nozzle pressure. If chemical isn't drawing, your nozzle is the first thing to check.
If you've confirmed the injector and nozzle and it still won't pull, work backward through the system: check the chemical container, supply line, and filter for blockages or air leaks, and keep chemical lines as short as possible.
Downstream Injectors Are a Wear Item
Downstream injectors do not last forever — treat them as a throwaway part, not something to rebuild in the field. The spring and check ball wear out, and when they do, your draw gets inconsistent. Our recommendation: keep a spare injector on the truck, fully assembled with quick connects, ready to swap. A $30–50 part shouldn't cost you an afternoon of production because you had to run to a supplier mid-job.
Make It Last: Rinse Thoroughly
Rinsing thoroughly after every use is the single best thing you can do to prolong injector life. Pulling clean water through the system flushes sodium hypochlorite and surfactants out of the injector, check valve, and lines before they can crystallize and eat away at the components.
Get the FlowPro System
We install the FlowPro remote downstream system on our Ultimate Mini skid, and we can build it into nearly any skid, trailer, or van setup we make. Browse all of our custom builds in our Pressure Washing & Soft Wash Builds collection. Already have a rig? Grab the complete Gen 5 FlowPro system with mounted bypass, watch the walkthrough above, and add remote-controlled downstreaming to your current setup.
Questions about downstreaming setups or adding the FlowPro to a build? Call us at 503-403-6185 or stop by our shop in Oregon City, OR. We build this equipment because we ran it ourselves for over a decade — and we're happy to help you get your system dialed in.
