Downstreaming is how most of the house washing in this industry gets done. It's fast, it keeps bleach out of your pump, and once it's set up right it just works. It's also the single biggest source of "my rig won't pull soap" phone calls we get at the shop, and the thing new guys get the most conflicting advice about.
We ran our own washing business for over ten years on trailers, box trucks, flatbeds, vans and skids before we started building equipment for other people, and with 300-plus builds out working in the field we've talked to a lot of contractors, done a lot of research, and listened closely to what people complain about on their rigs. This guide is everything we know about downstreaming in one place: how it works, the three ways to set it up, how to size the injector, what to put in the bleach tank, how strong the mix should be for your machine, and what to check when it quits pulling.
What downstreaming actually is
A downstream injector is a small venturi that sits in your pressure line after the pump and unloader. Water flowing through the narrow orifice inside it speeds up and drops in pressure, and that pressure drop pulls chemical up a 1/4" hose from your bleach tank and into the water going out to the gun. The chemical never touches the pump, which is the whole point. Bleach through a pump eats seals, check valves and warranties. Upstreaming, where chemical is drawn in before the pump, is something nobody who runs equipment for a living does with sodium hypochlorite.
The injector only pulls when there's low back pressure after it, which is why you downstream with big low-pressure soap nozzles and not with your rinse tips. Put a small high-pressure tip on and the pressure in the hose climbs, the venturi loses its suction, and the draw stops. That one fact explains about half of all downstreaming problems, so keep it in your back pocket.
Because the injector is mixing a little bleach into a lot of pump water, what comes out the gun is a mild mix, usually somewhere around 0.5% to 1.2% sodium hypochlorite depending on your machine. That's exactly what vinyl, painted siding, aluminum, gutters and most building exteriors want. It is not what a roof wants, and we'll get to that.
The three ways to set up a downstream system
Every downstream setup has the same parts doing the same job: an injector in the pressure line, a 1/4" draw hose going into the bleach, and some way to switch from bleach to water for rinsing. They all draw about the same. The difference between them is how much walking you do.
1. The drop stick and a General Pump injector
This is the most common setup in the industry and the one most guys start with. A General Pump Hi-Draw fixed injector (around $20) snaps into the pressure line after the pump. We put it between the whip line coming off the unloader and the hose reel, with stainless quick connects on both sides so it swaps out in seconds. A 1/4" poly braid hose with a chemical filter on the end runs from the injector's barb and drops straight into the bleach.
When you're soaping, the drop stick sits submerged in the bleach. When you want to rinse, you pull it out of the bleach and drop it into your water buffer tank (or a bucket of water if your setup doesn't have a buffer tank), and now the injector is drawing water. That's your rinse cycle, and it's also rinsing the injector out every time you do it, which is a big part of why this simple setup lasts.
One trick we build into every one of our setups: slide the 1/4" hose through a piece of 1/2" schedule 80 PVC riser tube. It's the gray pipe sold in the sprinkler section at the hardware store for a couple of dollars. The hose runs through the pipe and the filter nests into the bottom of it. The pipe keeps the hose straight, adds weight so the filter stays fully submerged, and stops the loose hose from floating up to the top of the bleach and sucking air. A collapsed or floating draw hose is one of the most common reasons an injector that worked yesterday is pulling air today, and a dollar's worth of PVC fixes it for good.
2. The manual downstream bypass
A downstream bypass assembly puts a ball valve in a loop around the injector. Turn the valve and water goes around the injector instead of through it, so the draw stops with the turn of a handle instead of a trip to the bleach tank. It also gives you full flow with no injector restriction when you're surface cleaning. You still walk back to the truck to flip it, but you're not fishing a drop stick out of a jug.
3. Remote control: the Gen 5 FlowPro
The Gen 5 FlowPro remote control downstream system is the one we recommend and one of the most popular options we add to our builds. It's a remote-controlled bypass. You hit a button on a waterproof remote clipped to you and the system switches from mix to rinse and back without you walking to the truck. On a two-story house with 200 feet of hose out, that's a lot of saved steps over a day, and the time you'd spend walking is time the soap is already dwelling.
The FlowPro draws the same as a plain injector because it is a plain injector with a bypass and a remote. What you're paying for is not walking. If you're new to it, our FlowPro setup and operation guide walks through installation and the handful of things that trip people up.
Add a rinse valve to either one
On the manual bypass and the FlowPro, we add a rinse valve: a 1/4" three-way ball valve on the draw side with two hoses plumbed in, one into the bleach and one into the water. Flip it one way and the injector pulls bleach; flip it the other way and it pulls water. At the end of the job you leave the system on "mix," flip the valve to water, and pull clean water through the injector for a minute. That flushes the check ball, spring and o-ring that bleach eats, and it's the single best thing you can do for injector life. A bypass or remote that only stops the soap leaves bleach sitting in the injector all night; a rinse valve gets it out.
Where the injector goes, and which one to buy
Get the injector a few feet off the pump. Water coming straight out of the pump is turbulent, and an injector hung right on the unloader draws worse and puts weight on fittings that don't want it. On our builds the unloader is mounted on a block, a whip line runs from there, and the injector sits at the end of the whip right before the reel. Plumb it with the arrow pointing away from the pump. Installing it backwards is the first thing to check when a brand-new injector won't pull, and more than a few experienced guys have done it.
Injectors are sized by orifice, in millimeters, and the number has nothing to do with draw ratio. A 1.8 mm is sold for 2 to 3 GPM machines, a 2.1 mm for 3 to 5 GPM, and a 2.3 mm for 5 to 8 GPM. The rule most pros follow is to go one size smaller than your machine once you're running 150 to 200 feet of hose, because the smaller orifice makes a stronger pressure drop and keeps pulling through the extra hose. That's why the 2.1 is the workhorse of this industry: it's on 4 GPM, 5.5 GPM and 8 GPM machines alike. A 2.3 is fine on an 8 GPM with a short hose run. Don't go two sizes down. A 1.8 on an 8 GPM chokes the flow enough that you lose the reason you bought an 8 GPM.
Run 3/8" pressure hose, not 5/16". A properly sized GP injector on a 4 to 8 GPM machine will pull through 200 feet of 3/8" all day, and plenty of guys run 250. Every quick connect between hose sections adds restriction, so if you're joining hoses to get there, fewer joints is better. The built-in injector on a consumer-grade machine is a different animal: most of them won't pull past about 50 feet of hose. Plug it or pull its orifice and add a real injector after the unloader.
One more thing on machine size: we don't recommend downstreaming with anything smaller than a 4 GPM. A 2.5 or 3 GPM machine can be made to pull with a 1.8 injector and a short hose, but the draw is unpredictable, the flow is too low to rinse a house in a reasonable time, and you'll fight it on every job. A 4 GPM is the realistic floor for downstreaming a house; if you're buying your first machine, start there.
For most people the brass GP Hi-Draw is the right buy. It's around $20, it's the standard, and it's a wear item no matter who makes it: the brass body outlasts the ball, spring and o-ring inside it by years. The stainless GP is the same injector in a body that shrugs off chemical, which matters if you're running acids or just hate replacing things. Either way, keep two or three spares made up with quick connects on the truck. Injectors fail on their own schedule, sometimes between one house and the next, and occasionally right out of the package.
Skip the adjustable injectors
We don't recommend any of the adjustable downstream injectors, the ones with a dial or knob on top. We've watched them fail after the first or second use, the dial walks on you with vibration, and there's simply more in them to go wrong. If you've got one, keep it as a backup or throw it away, but don't make it your primary injector. A fixed Hi-Draw costs less and does the job better. If you want to control your mix, do it in the bleach tank with water, not with a knob on the injector.
Start with good, strong, fresh 12.5% bleach
Downstreaming dilutes whatever is in your tank ten or more times over, so you can't start weak. Use 12.5% sodium hypochlorite, sometimes called pool shock or liquid chlorine, from a pool supplier, chemical distributor, or a shop like ours that moves a lot of it. Laundry bleach at 6% isn't strong enough to downstream with on anything bigger than a small machine, and the store brand is often weaker than the label.
Fresh matters as much as strength. Sodium hypochlorite is made closer to 15% and labeled 12.5% because it starts losing strength the day it's bottled. Heat and sunlight speed that up. Bleach that's sat in a hot trailer for a month can be down near 9% or 10%, and a lot of "my mix isn't working" is really "my bleach is old." Buy what you'll use in a week or two, keep it out of the sun, and if you're running a hot trailer, get some ventilation in it. If you're local, we sell fresh 12.5% by the gallon at the shop in Oregon City.
If you want to know what's actually in your drum instead of guessing, a chlorine hydrometer from the pool aisle will tell you in a minute: float it in a sample and read the percentage off the stem. It's a cheap way to settle the "is it my mix or my bleach" argument, and it turns "the bleach is old" from a hunch into a number. Short of that, use your nose and your calendar. Fresh 12.5% has a sharp bite; bleach that smells flat and has been sitting in a hot trailer for a month is weak, and your tank mix should be adjusted to match.
Always add surfactant to the bleach
Bleach kills the organic growth on a house. Surfactant is what makes it stay there long enough to do it. Without surfactant, bleach hits vinyl siding and runs right off, so you're using more product and getting less dwell. With it, the mix clings to the wall, stays wet, and you can see where you've sprayed. Surfactant also helps the house rinse cleaner. This is true whether you're doing a house wash, a building wash, or pre-treating or post-treating concrete.
Our Apple Suds, Lemon Suds and Cherry Suds are bleach-stable surfactants with a booster built into the formula that helps the bleach work better, so you're getting cling and a stronger-acting mix from the same jug. We mix it straight into the bleach tank:
- Apple Suds or Lemon Suds: about 1 ounce per gallon of bleach in the tank.
- Cherry Suds: about 1/4 ounce per gallon of bleach. It's a double-thick concentrate, so it takes a lot less.
More is not better. Too much surfactant means suds everywhere and a house that takes forever to rinse. Pour some bleach in first, add the surfactant, then top off with the rest of the bleach so it mixes without foaming up an empty tank. And use a real bleach-stable surfactant. Dish soap breaks down in sodium hypochlorite and leaves residue; we ran the numbers on that in Dish Soap vs. Bleach-Stable Surfactant.
How strong to run the mix for your machine
This is where most of the confusion lives, so here's the key idea: the bigger your machine, the weaker it draws. A downstream injector pulls a roughly fixed amount of chemical, and a bigger pump pushes more water past it, so the same injector that gives a 4 GPM machine a strong mix gives an 8 GPM machine a thin one. That's why you dilute the bleach on a small machine and run it straight on a big one.
Our starting points, based on what works for us and for the contractors running our builds:
| Machine | What goes in the bleach tank | Why |
|---|---|---|
| 4 GPM | 4 gallons 12.5% bleach to 1 gallon water (plus surfactant) for about a 1% wash; 3 gallons water to 2 gallons bleach for a milder wash on a lightly soiled house | A 4 GPM draws strong, around 7:1 to 10:1. Straight 12.5% is hotter than siding needs and wastes bleach, so cut it with water. |
| 5.5 GPM | Straight 12.5% bleach (plus surfactant) | Draws around 10:1 to 14:1, so straight bleach lands about 0.8% to 1% on the wall. That's a little stronger than the same tank gives you out of an 8 GPM, so keep an eye on delicate surfaces and cut it 50/50 for a lightly soiled house. |
| 8 to 10 GPM | Straight 12.5% bleach, no water | Big machines pull a thin mix by nature. Dilute it and it won't clean. |
Want the numbers for your exact machine, hose length and tank size? Run them through our downstream calculator. It picks the injector and nozzle too, and if you've bucket-tested your rig it uses your real draw.
Those are starting points, not gospel. Every rig draws a little differently depending on the injector, hose length, nozzle and how fresh the bleach is, so play with your dilution and find what works on your equipment. The wall will tell you. If the green on the siding starts turning brown and letting go within a few minutes, you're right. If it vanishes the instant the mix hits, you're too hot; add water to the tank. If nothing's happening after five to seven minutes, you're too weak or your bleach is old; add bleach.
Weather plays a big part too. Bleach works faster when it's warm and slower when it's cold. In summer, soap smaller sections so nothing dries on the siding or the windows, and keep the plants watered. In cold weather, go a little stronger or give it more time; a mix that was perfect in July will be slow in November, and the shady north side of a house always needs more dwell than the sunny side.
Know your real draw: the bucket test
Injector packaging says things like "up to 20% draw" or "10:1." Treat that as marketing. A GP Hi-Draw on a 4 GPM machine typically pulls somewhere around 7:1 to 10:1 through 200 feet of hose; the same injector on a 5.5 pulls 12:1 to 15:1; on an 8 GPM it's more like 15:1 to 18:1. The only way to know yours is to test it, and it takes three minutes.
Put your normal hose and your normal soap nozzle on. Drop the draw stick into a gallon jug of water (water is close enough to bleach for this). Spray into a 5-gallon bucket for exactly one minute, then measure how much came out of the gun and how much left the jug. Divide the water by the chemical and that's your ratio. Write it on the machine, or type both numbers into the downstream calculator and let it do the mix math from your real draw. Now you know what the injector does when it's healthy, and you'll know the day it starts lying to you.
The math from there is simple: the strength in your tank divided by your ratio plus one is what's hitting the wall. Straight 12.5% through a 10:1 injector is about 1.1%. Straight 12.5% at 15:1 is about 0.8%. A 50/50 tank (6.25%) at 10:1 is about 0.6%. Three water to two bleach (5%) at 7:1 is a little over 0.6%, and at 5:1 it's about 0.8%. Most siding cleans beautifully anywhere from 0.6% to 1%, and 1.2% will clean just about anything you should be downstreaming in the first place.
House wash targets by surface
Most of the arguments about mix strength go away once you stop thinking about the tank and start thinking about what's landing on the wall. Here's where we aim, surface by surface, and whether a downstream injector can get you there with straight 12.5% in the tank. Treat the percentages as starting points and let the wall tell you the rest.
| Surface | Target at the wall | Downstream it? | What to watch |
|---|---|---|---|
| Vinyl siding | 0.6% to 1% | Yes | The bread-and-butter house wash. Go to the low end on a lightly soiled house; a second coat beats a hotter mix. |
| Painted wood, Hardie and fiber cement | 0.6% to 1% | Yes | Chalky, oxidized paint will wipe off on your finger no matter what you spray. Low pressure only, and set expectations with the customer before you start. |
| Aluminum siding | Low end, around 0.6% | Yes | Mild mix, soft rinse. Any real pressure strips the oxidation and leaves streaks you can't fix. |
| Gutters (outside faces) | House wash mix | Yes, for the green | Bleach takes off the organic growth. The black tiger stripes are oxidation and need a gutter cleaner (see below). |
| Light stucco and brick | About 1% | Yes, usually two passes | Porous, so it drinks the mix. Keep it wet and come back with a second coat before you reach for more bleach. |
| Heavy stucco, Dryvit and porous brick with real growth | 2% to 4% | No | Out of reach for an injector. A 12V system, an X-Jet, or a pump-up sprayer for the bad spots. |
| Concrete pre-treat and post-treat | House wash mix | Yes | Ordinary driveway work downstreams fine. Heavy black algae and lichen want closer to 3% from a dedicated pump. |
| Asphalt shingle roofs | 3% to 6% | No | Batch-mixed tank and a 12V soft wash pump. There is no injector that gets you there. |
| Composite decking, stained or painted wood | House wash mix, low end | Yes, with a test spot | Test an out-of-the-way spot first and rinse well. Bare wood is a different story (see below). |
| Windows and screens | Whatever the wall gets | Yes | Rinse glass right away and never let the mix dry on it. |
If a number in that table isn't reachable on your machine with straight bleach, the downstream calculator shows you the honest ceiling instead of inventing a mix that doesn't exist.
The gun and nozzle
Bleach is hard on guns. Cheap guns get stiff, leak at the trigger, and the brass inside corrodes until they restrict flow enough to kill your draw. The gun we run and build in house is the chemical-resistant ST-2315 house wash gun: a Suttner ST-2315 body with a ceramic ball, assembled with stainless quick connects and a 6" stainless lance. The ceramic ball doesn't care about sodium hypochlorite, the 12 GPM-rated body doesn't choke a big machine's draw the way smaller homeowner guns do, and the short 6" lance straightens the stream just enough without the weight of a long wand. We tested that gun for years in our own washing business before we ever sold one.
On the end of it, we like the M5 Twist downstream nozzle. Instead of a pocket full of color-coded tips, you twist the head to go from a tight stream for reaching a second-story gable to a wide fan for the first floor, and it's a low-pressure nozzle the whole way, so the injector keeps pulling. Buy it sized to your machine: 3 to 7 GPM for a 4 or 5.5, 7 to 12 GPM for an 8. If you'd rather run fixed tips, a stainless downstream J-Rod with chemical-resistant nozzles already installed does the same job, and a shooter tip gets you to three-story peaks and through a breeze. More on what we ran and why in Pressure Washing Guns, J-Rods and the M5.
Whatever nozzle you use, understand that bigger orifices draw more soap, not smaller. A 0040-size soap tip is the minimum for a 2.1 injector; 0030 and 0050 draw just fine. If you need more chemical, pop the nozzle off entirely for a second and watch the draw jump. And don't fall into the habit of switching to a high-pressure rinse tip to "shut off" the soap on siding. If the tip makes enough pressure to stop the injector pulling, it makes enough pressure to strip oxidation off aluminum, drive water behind vinyl, and blast mulch into the flower beds. Soap and rinse with the same low-pressure nozzle, and stop the soap at the truck with the drop stick, the rinse valve, or the remote. That's what those setups are for.
Why your injector isn't pulling
When a downstream system quits, it's one of a short list of things. Work from the gun back toward the pump and change one thing at a time.
- Wait for it. Soap takes 15 to 20 seconds to travel 200 feet of hose. Hold the trigger before you decide it's not working.
- Check the arrow. Flow goes through the injector in one direction. Backwards, it will never pull.
- Pull the nozzle. If it draws with no tip but not with your tip, the tip is too small or plugged, and you've got too much back pressure. Go up a nozzle size, or clear it.
- Pull the gun. If it draws with the hose open and not with the gun on, the gun is restricting flow. Corroded brass, trash caught in the trigger valve, or a small-bore homeowner gun on a big machine all do this. That's the problem a 12 GPM-rated chemical gun solves.
- Shorten the hose. Try it on 50 feet. If it pulls there and not at 200, drop one injector size (2.3 to 2.1, or 2.1 to 1.8) or take the quick connects out of the middle of the run.
- Check the draw line for air. Pull the hose off the barb and put your finger over it; you should feel strong suction. If the injector sucks your finger but not the bleach, the hose has a split, a loose fit on the barb, a collapsed section, or a filter stuck flat on the bottom of the jug. Any air leak on the suction side beats the chemical to the injector every time. The riser tube trick above prevents most of this.
- Free the ball. The check ball inside the injector gums up in bleach and sticks. Push a toothpick or a piece of wire into the barb and wiggle it. This fixes more injectors than any other step, and brand-new injectors can be stuck right out of the package.
- Check for backflow. If water is pushing out of the barb or trickling back into your bleach tank, the ball, spring or o-ring is shot and your mix has been getting weaker all day. Replace the injector.
- Swap in a spare. Injectors are loose-tolerance, mass-produced parts. If everything else checks out, put a known-good one on. If the spare pulls, you've found it.
Two things that are not the problem: the machine, and the idea that two injectors in a row will pull twice as much. Only one injector in a line draws; stack them and the second one just adds back pressure to the first. Same with the "dual barb" injectors: two barbs split the same draw, they don't double it.
And one thing that is normal: a 2.1 injector on an 8 GPM machine whistles. Loud. Get worried when it goes quiet.
Keep it working: maintenance
Rinse the injector with clean water after every job, not at the end of the day. Pull the drop stick into water, flip your rinse valve, or hit rinse on the remote and give it a minute. The ball, spring and o-ring inside the injector are what fail, they fail because they sit in bleach, and a minute of water is the difference between an injector that lasts a season and one that lasts a week. Our rig maintenance guide has the full schedule for the rest of the plumbing.
Use a plastic strainer on the drop line, never a metal mesh one and never one with a metal check ball in it. Metal in bleach corrodes shut in days and shows up as a slow, mysterious loss of draw. Keep the draw line short, a few feet, and replace it when it goes stiff. Keep spares of the injector, the 3/8" quick connects, and the 1/4" barb fittings, because those are the parts that live in chemical. Stainless quick connects outlast brass ones around bleach by a wide margin.
When an injector dies, replace it. Rebuild kits exist, but by the time the internals are gone the barb is usually corroded too, and a new Hi-Draw is around $20. It's the most disposable part on the rig. Budget for it the way you budget for fuel.
What downstreaming can't do
A downstream injector tops out around 1% to 1.2% at the wall with straight 12.5% in the tank, and there's no injector, check valve, or gadget that changes that physics. Any product promising 3:1 or 5:1 from a venturi on a pressure washer is selling you something. That's plenty for house washing, which is 90% of the work most residential companies do. It is not enough for:
- Roofs. Asphalt shingle needs 3% to 6% depending on how bad it is. That's a 12V soft wash pump and a batch-mixed tank, not a downstream injector. Our soft wash mix calculator gives you the bleach and water for any strength and tank size.
- Heavy stucco, Dryvit and porous brick with real growth. Usually 2% to 4%. A 12V system, an X-Jet, or a pump-up sprayer for the bad spots.
- Lichen and heavy concrete pre-treat. About 3%. Same answer.
Light stucco and brick, and ordinary driveway pre-treat and post-treat, downstream fine; you may need a second pass. When a house wash mix isn't getting it done on siding, the answer is usually not a hotter mix. It's dwell time and a second coat. Dwell is the most underrated tool on the truck. If you're deciding between a downstream-only rig and a full soft wash system, our 12V soft wash pump guide and what size pressure washer you actually need will help you sort it out.
Downstream injector vs. X-Jet vs. 12V vs. proportioner
When people ask us which way to go, this is the comparison we draw on the counter:
| Method | Strength at the wall | Best for | Trade-offs |
|---|---|---|---|
| Downstream injector | About 0.5% to 1.2% with straight 12.5% in the tank | House washing, building exteriors, gutters, ordinary concrete pre- and post-treat. Ninety percent of residential work. | Capped by the venturi. Around $20, and it rides on the machine you already own. |
| X-Jet M5 (bucket-fed, on the gun) | Up to roughly 4% to 5% from a bucket of straight 12.5% with no proportioner tip; less with one | Spot-hitting stucco, brick and heavy growth without a second pump; a hotter patch on an otherwise downstream job. | You carry the bucket and the draw hose hangs off the gun. Great tool, awkward for a whole house. |
| 12V soft wash system | Whatever is in the tank: batch-mixed 1% to 6% | Roofs, heavy stucco and brick, lichen, anything above the injector ceiling. | Separate pump, tank, hose and reel, and the pump sees bleach, so it's a wear item. Our 12V guide covers it. |
| Proportioner / metered system | Dialed in on the fly | Crews doing houses and roofs all day who want one hose for both. | More plumbing, more cost, more to maintain. Overkill until the roof work justifies it. |
When bleach is the wrong chemical
A good share of the "my house wash mix isn't working" calls aren't a strength problem at all. The stain isn't organic, so no amount of sodium hypochlorite is going to move it. Before you crank the mix, make sure you're fighting the right thing:
- Oxidation on vinyl, aluminum and painted metal. That chalky haze that comes off on your hand is the surface itself breaking down, and bleach doesn't touch it. Use a dedicated oxidation remover like Ox Killer and keep the pressure down.
- Gutter tiger stripes. The black streaks on the outside of gutters are oxidation and road film bonded to the finish. House wash mix takes the green off and leaves the stripes. Gutter Butter is what we sell for them.
- Rust. Battery stains on a driveway, sprinkler rust on a wall, fertilizer specks on concrete: bleach won't budge them and can make some of them worse. Use a rust remover like Rust In Peace.
- Oil, grease and tar. Driveways, drive-thrus, dumpster pads. That's degreaser work, with hot water if you've got it. We stock several, from Gold Assassin to HD Degreaser.
- Efflorescence. The white mineral bloom on brick, block and pavers is salt coming out of the masonry. Bleach does nothing for it; it takes an acid-based masonry cleaner and a careful rinse.
- Bare wood. Bleach breaks down the wood fibers, leaves cedar fuzzy and gray, and corrodes the fasteners. For decks, fences and anything else that's bare wood, use a bleach-free cleaner like ClenzO2 instead; our ClenzO2 how-to walks through it.
Get the chemistry right and the downstream rig handles the rest of the house like it's supposed to.
Plants, dwell and the rest of the job
Wet the landscaping before you soap, keep it wet while the mix dwells, and rinse it again when you're done. House wash strength is mild, but it will still burn a dry hydrangea. Tape or bag outlets, keypads and doorbells, and go easy around the meter base. Work bottom-up when you soap so you don't streak, let it dwell five to ten minutes, and never let it dry on the house or on the windows. Then rinse top-down with the same low-pressure nozzle until the water runs clear. If a strong mix hits a window or a shutter, rinse it right away.
Wear eye protection and a respirator rated for chlorine. Bleach fumes add up over a career, and the guys who've been doing this twenty years will tell you so.
What we put on our builds
Every pressure washing skid, trailer and van we build downstreams the same way: a block-mounted unloader, a whip line to a GP Hi-Draw injector at the reel, stainless quick connects, and a 1/4" poly braid draw line in a PVC riser tube with a plastic filter on the end. Bypass and FlowPro setups get the rinse valve. The gun we hand you is the chemical-resistant ST-2315 house wash gun, and the M5 Twist is the nozzle we tell people to put on it. The Gen 5 FlowPro remote is the upgrade most customers add, and once you've run one you won't go back. We build it like we were going to run it ourselves, because for ten years we did.
If you're putting a rig together or want help getting an existing one to pull right, book a 30-minute discovery call with Tim or Kristina, stop by the shop at 13896 S Fir St Suite B in Oregon City, Monday through Thursday, 8am to 4pm, or call 503-403-6185. Bring the injector. We'll figure it out at the counter.
