DIY Softwash Metering System


What would you suggest to plumb from the check valves to the double wye instead of polybraid? I haven’t found the double wye with threaded sockets but I’ll ask Monday if it’s available. Might just be uncommon… I’m thinking all PVC fittings. Does that sound ideal?

I called the chemline valve rep today and the do offer all the valves with threaded female sockets instead of unions.

Does it hurt to use 1" for the soap? If it doesn’t hurt, why not just make them all the same size for simplicity?

@Racer, what diameter hose do you use to draw soap? Is it sufficient? Would it hurt if it were sized up to 1/2" or 3/4" or 1"?


Does anyone ever have the need to or would it be convenient to have more than 3 hookups and metering valves on the same system? For instance have water, SH, surfactant, and EBC all plumbed into a 4 way soft wash metering manifold that allowed you to use your softwash to apply any combination of any of your most used chemicals? It could look like this with 4 or 5 valves:

Valve 1: Water
Valve 2: SH
Valve 3: Roof surfactant
Valve 4: Elemonator (or or diluted Elemonator mix in bucket)
Valve 5: EBC

You could do a roof, then a house, then a driveway, then a dumpster pad or drive-thru all with your softwash setup and without ever mixing chemicals, changing drop tubes, or anything else. Any unused or not needed valves could be capped off or plumbed to numbered dropsticks or something.

So if you could pick, how many options would be ideal for blending all through the same metering system? I appreciate any feedback. I’ve got an idea in my head that I think would be cool, but want to hear from you guys that are softwash experts.

@Racer @tireshark @Atlas1 @AquaTeamPowerWash @squidskc @Innocentbystander @BuzzLightyear @Alabama @Greg755 @Infinity and anyone else who softwashes?


I’m tagged in such esteemed company! Winning!

Easy. All you need is a switch on the surfactant line. Like @Infinity uses to flush his injectors he will know what it’s called.

Turn the dial to select which bottle of chemical is sucked thru the surfactant metered valve. Remember to adjust the metered valve on proportioner to the correct % for each chemical.

Sorry for vague answer. Shivering with a broken bike in the dark but atleast my emails are working lol


That three way valve @Infinity


@jzbreeland, this is what I use for rinsing out my downstream injector. It could be used to switch between two different surfactants as Buzz is suggesting.

I’m definitely not a softwash expert. I don’t have a dedicated softwash pump; I just use my downstream injector and occasionally the xjet. So take what I have to say with a heaping spoon of salt.

I think 3/4” or larger would be way overkill for the surfactant lines. I think it might be difficult to dial it down enough to get the proper proportions. I’m not sure how easy it would be to crack open one of the larger metering valves so that it’s only putting in .5% soap or whatever is required for a particular application. I think probably the ideal size would be 3/8” plumbing. 1/4” might be just a tad restrictive for someone doing 10+ gpm. And the more 3-ways or manifolds you add to that line, the more restrictive the whole thing becomes.

And I actually think a manifold might be the way to go on the surfactant side, with some type of 3-way system beforehand for flushing with water before switching between surfactants that may be reactive to one another.

I think the ideal system would allow for you to switch between all sorts of chemicals, and dial your flow rate up or down as needed. I know right now you’re only dealing with the mixing end of the formula, but if you’re looking for the most versatile solution possible, you need to think about what different types of delivery systems may be used with it. Whether that will be air diaphragm, 12v, booster, etc.

Just my 3¢ (because my 2¢ ain’t worth as much as everyone else’s :smirk:)

PS: how are these metering valves with handling chemicals harsher than SH, like sodium hydroxide? Do they have viton or kalrez internals?


If you understand your kitchen faucet then you understand a mixing valve. If you have a combo tub shower valve then you understand a mixing valve with a diverter feature.
Theoretecly you can add as many valves as you want. The closer you can get the pressure and GPM from each line going into the manifold to be the same, the more accurate/consistant your valve settings and mix will be coming out of the manifold.
Some chemicals don’t play well together and to pump them together through the same pump/ lines/guns would not be a good choice in my opinion. So now your back to flushing out the system every time you use a different chem.
If your working with only one pump and your tryinCg to control things from the suction side, then that’s even more valves and headaches… Of course then you could really go crazy and buy chemical injection pumps and tie them into the sysyem up stream.
More parts equals more money, more things to break, more things to go wrong and a steeper Learning curve.


These are screenshots of two chemical resistance charts that gives rating between a given chemical and a given material and how they behave with one another. Not sure if you guys use these already maybe? I can give links to the actual files online if anyone wants. As you can see, sodium hydroxide gets an “A” rating from both PVC and polypro (both aren’t on the Banjo chart like they are on the other), but doesn’t do well with Viton. Some forms or concentrations of sodium hydroxide does okay with EPDM, but I am not sure which kind you would possibly use.

The good news here is that Hastelloy rates an “A” with both SH and sodium hydroxide. That means that the check valve with Hastelloy internals will hold up well with these chemicals. Still probably not as ideal as a diaphragm check valve, but for 1/10th the price or less, that’s very likely the most matched and cost effective way to prevent back flow here.

Thanks for suggesting 3/8" @Infinity. The interesting this is that the GF 523 metering valves (the ones everyone else is using) are only available in 3/8" and 1/2", so you can’t go any larger. The other manufacturer I found that makes a 180 degree meter valve starts at 1/2" and goes up to 2" lol. The OCD in me wouldn’t like mixing the two manufactures together because it’d look bad in my opinion lol. Do you think 1/2" metering valve / check valve / rigid plumbing would be okay for surfactant / soap? This 1/2" part of the valve could still be supplied with 3/8" hose, or 1/2" hose. I guess that would be up to the end user. But if the manifold was designed with 1/2" parts for soap and 1" parts for water and SH lines, do you think that would be manageable? Thank you so much for your input!

@Infinity, could you also talk about how the metering manifold might need to be different in order to accommodate booster pumps or AOD pumps versus just 12V pumps? I was under the impression that they all worked basically the same, with 12V having it’s limitations in pressure and flow, but the other systems being much more costly to purchase and use. It looks like 1" is good up to 16GPM on the suction side of a pump with little to no pressure (image below). That should be plenty. However, if you look at 1/2", it’s only rated up to 7GPM on the suction side, so I can see that a system like this built with all 1/2" components might limit performance of a delivery system that is designed to do more than 7GPM. Is this what you are talking about?

@Greg755, Do you have any ideas on a super simple and economical way that soap lines or even all lines could be flushed with water without restricting and complicating everything with 3 way valves? I’m trying to think outside the box a little bit, but I feel like an additional 3 way valve on each individual line would be the only way to effectively accomplish this. Do you have suggestions?

Also @Greg755, if I was able to give you individual metering valves for water, SH, and 2 or 3 soaps (so 4 or 5 total) AND give you a way to flush EVERYTHING at once with one valve (instead of having individual 3 way valves for each line), that would keep costs down, design simplistic, and flushing quick and easy. What would you think if that was possible?

Thanks for your input so far!


First is dip tube on each line instead of plumbed. Second is a ball valve and a tee on the water tank and each of the other lines which is a little more cost and you have to make sure you remember to check all the valves prior to each action. Check valves make things simpler but are more expensive restrict flow and when they mal function you have to figure out what’s going on… For example you can get a valve that partially opens and you may not even realize that instead of 50 percent Sh your only getting 20 percent Sh even though you sticker says the valve is at 50% on the other side if it doesn’ten or seat properly you contaminate your other chefs and may not even realize it…
One guy I know has a ball valve on all his lines coming from the tank and then a quick connect. To flush he turns off the ball valve the tables the disconnect off and attaches it to a water pump and runs it for a while when its flushed he just reversed the process… Usually you can’t get cheap, convient and bullet proof all at the same time… I prefer cheap and bullet proof over expensive and convienant…


That’s the way the Pro Portioner is built, right? Except I think they only use 1/4” supply line? Seems to work for them. I guess my concern was with having completely unrestricted flow on the soap supply. Shouldn’t matter if that restriction happens in the hose or the valve.

Yeah, I’m not really sure what I was trying to say there. Disregard as you see fit, lol.

Very important point there.

I think a possible middle-of-the-road solution would be using double shutoff quick connects for the surfactants, instead of drop tubes. Then you could also mount one of the quick connects to your water tank and flush the surfactant line before drawing a different soap. But I’m not sure what you’d do about switching between your actual chem tanks, like SH, lye, acid based cleaners, etc.
Seeing how the applications for lye and acid based cleaners are usually more limited than SH (roofs), having a separate, dedicated pump for those would probably make the most sense. I think we’re already going in the direction of overcomplicating things.


Yes, I think a large question here is what should be built into the metering system and what should be left for the operator to do himself. A metering system with 3, 4, or 5 inlet valves / inlet lines could be plumbed to whatever permanent tank or drop tube or whatever the operator sees fit to plumb it to. Also, 3 way valves for flushing could be added independently and plumbed as the operator sees fit, or not plumbed at all. Basically the operator could get chemicals / soap / water into whichever inlet line he wants and however he wants. Perhaps that shouldn’t change.

Do you guys feel like having the option for 4 or 5 different incoming lines is useful over just 3? The additional cost would basically just be the metering valve and check valve, so probably ~$100 or so per line since the fittings are negligible. Or is just 3 lines the most convenient and efficient?


Excatly… Simple is better, most of the time.


Ok so I have a question. Why wouldn’t making something like this work? Besides getting the metering ball valve, at least. That would be the only pricey part.


I think this could work for someone, but it’s the most rudimentary you could put together with some functionality. So yeah, you can. But I think there might be a few issues.

  1. Metering ball valves meter flow. Ball valves turn flow on or off. They don’t meter. You can try to meter it, but you won’t have any real control over your ratios. The actual ball itself in a metering valve is different, which gives you the metering fuction (it’s not just based on how much you open a regular ball valve). See image below for the side cutaway view of the GF 523 metering valve.
    33 PM

  2. Check valves prevent backflow and contaminating your mix sources with your other sources. The setup you showed in your picture doesn’t have check valves. Most check valves also have stainless steel components inside, which will corrode really quickly with SH exposure. One solution is to get a check valve with Hastelloy, but it’s not as readily available and costs slightly more. The ideal solution, in my opinion so far, is a diaphragm valves, but those are 10x the cost.

  3. 90 degree angles restrict flow. Sure, the elbows are easy to get. Sure it’s probably not a big deal. But when you are just working with 12V pumps, it might be enough to make a difference.

  4. Valve sizing. Not sure, but the things in your photo look like 1/2". I think that’s what most are using. But we’ve been having the discussion about upping everything for water and SH to 1" and using 1/2" for detergents.

  5. Custom manifold. I’ve emailed a plumbing supplier in my area to inquire about having a custom 3-to-1, 4-to-1, or 5-to-1 manifold made to mate the metering ball valves / check valves all together and into the same outlet. This would minimize fittings and also allow smoother turns and less restriction, plus really simplify the metering system as a whole. I think this would be an upgrade over piecing together different fittings.

Also, nothing I say means too much. I don’t even have softwash equipment. I’ve just been researching and looking at ways to do it better and more effectively and more economically when I get to that point and for other people who might be interested and not super willing to pay $1200 or whatever other super premium costs are associate. :slight_smile:

Also, did you make that in the plumbing aisle at Home Depot? lol. That’s totally on the floor at Lowes or Home Depot lol.


Lol it’s 100% something I put together at Lowe’s. I was walking around and was reminded of this thread so I went and made something similar. I was using a 1" cross and everything else was 3/4". I agree about the 90 degree, but they didn’t have that stemming type that was pictured earlier. As for the check valves, I was trying to find a way to get them attached, but I couldn’t find any adapter to fit for some reason. They are only like 6 bucks at Lowe’s. Just considering a cost effective way to go about it. I agree with getting a metering ball valve for precision, but those aren’t cheap either lol.


This is how I swap between soap and water. I was gonna put them on remotes, but too many projects not enough free time. These are stainless steel. I have never had luck with the poly valves.


I like this. The operator can set this up themselves and flush the metering system out however he wishes. I think this is more cost effective and allows for greater flexibility depending on person preference and truck / trailer layout and space constraints. Thanks!


I’ve seen the parts at home depot. I wouldn’t feel comfortable using their check valves in this application. And they did have a double wye when I looked, but only in black PVC and it was in 1.5" lol. Way too large. Depending on the cost of a custom manifold, a 3-to-1 set up with custom single piece manifold, metering ball valves, and check valves could potentially come in less than $300 in material. Even if it were marked up 100% and sold at $600, that’s half the cost of the proportioner. Assuming there is no real discernible cost difference between a custom 3-to-1, 4-to-1, or 5-to-1 single piece manifold, the only additional cost per line would be 1 metering valve and 1 check valve. In material, that’s like $75 each. So maybe $375 for 4 metered incoming lines, $450 for 5 (material costs). I’m just guessing at it though for the custom manifolds. Hopefully I’ll hear back tomorrow if that’s something they can do and if so, what are the costs to get it designed and get tooling made. Maybe there isn’t much costs to that. I’ll definitely update on it though when I find out. I’m still planning to see if anyone likes the idea enough to commit to paying the material costs for the first one and giving it a try to see how well it works or if any components need to be altered, changed, resized, etc.


This is just for downstreaming. If you do a lot of softwashing I’d say spend the money on the Pro Portioner.

If you like tinkering and know how to use ball valves you can set up two ball valves to mix SH and water.

In my brain: If know how many gpm your 12v pulls at you can do a little math and just put your surfactant in with your SH and know that you’re getting .5 oz per gallon of mix or whatever. 2 different buckets will help to mark your valves with a paint pen at different ratios. Run 3-5 tests to make sure it’s pulling at that number or dang close.

My chem usage is usually just winging it. I don’t measure anything to the tick mark. Probably not the best, but works for me. I’m gonna put this on my list of stuff to make and test for after the season since everything I just said past “in my brain” is all just thoughts of a caveman and I haven’t done it.

I haven’t read the thread all the way through either, but I’m looking forward to it. The few comments I’ve read are dang interesting.


I certainly hope you’ll read it all and give me your thoughts / comments / suggestions. I’m not the expert here, nor do I want to give that illusion. I just think I can get a good price on high quality parts and maybe even compile a system more affordable and maybe with a little better flow. @Racer gives them impression that his lost 5 feet of reach is important.


Found some other potential metering valves. Looks like they don’t have the degree of rotation markings, but they might be a lot cheaper. Not sure yet. Also, take note of the one with the black handle. It says it has a special drilled ball for sodium hypochlorite… Any ideas what that means or why? Zooming in on the side of the valve, it says “body cavity vented upstream”… I’m emailing the manufacturer to get more information. Could be another alternative.