12V System Pulling Weak

I have a GF proportioner with a 12V system that I hardly ever used in the past, but I’ve finally been getting into some roof washes this year, and I’m not sure if my proportioner is pulling the % I want it to pull.
I have a drilled out DS injector that pulls a pretty hot mix and immediately cleans even the dirtiest vinyl or gutters, and when I spray soap on concrete with the DS system it looks wayyy more soapy than when I spray soap on concrete with the 12V system even if the SH valve is fully open to 6%. However everything runs good with the 12V system. It’s primed, sprays far, no air leaks, and works on-demand perfectly as it should. Is there any way to test how hot of a mix I’m getting out of the gun other than testing results on my customers roofs??

You’ll want to do a draw test.

Give that link a read, but basically:

  1. Only running water through your 12volt figure out the actual gpm your pump is putting out
  2. Put 64oz of water in a container and drop your 12V chem line in it
  3. Set your proportioner to the hottest setting and draw for a minute or until the 64oz is gone.
  4. Do some math to figure out how many oz of chem was pulled in a minute.
  5. Adjust your proportioner to a different setting and run the test again.

That should get you pretty close to the percentages/ratios of the dials.

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I’m more interested in this ‘drilled out DS injector’ thing.

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I didn’t physically drill mine, but I’m pretty sure it’s an option, because I’ve heard it called a drilled out injector and assumed I have the same thing. Basically one day my spring and ball came out of my downstream injector, and ever since that day it’s pulled a 2x hotter mix. Stuff used to take 3 applications to clean dirty vinyl, now it’s one and done. The only downside is that you can’t control when the downstream is on/off depending on pressure, it’s just always on. But I already had my downstream injector plumbed to a 2 way valve that goes to water and SH so that I can flush my injector out between jobs, so it works perfectly. I just keep it on water all the time, and then whenever I’m ready to use soap I just flip the valve, and flip back when I’m done soaping to rinse. It’s really nice.

Thank you!!! This helps a ton!

ALL injectors are always “on”. You’ve eliminated the internal components of the check valve assembly. You do know you’re now back feeding water into your chemical when your ball valve/trigger gun is closed right?

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Believe me I’m not. I’d know if I was. Chem tank consistently goes down in proportion with how much chem I’ve used, and it’s never diluted. I even used my tank from like 50 gals down to like 3-4 gals emptying out the tank and the strength of chem staged the same

To be able to never have flow come out of the chemical inlet in your injector you would never be able to turn off the flow of water from the pump. IE turning off the ball valve or closing a trigger gun.

I close my ball valve or turn off the trigger on my gun for long periods of time. Very long. 5+ minutes very often.

I’m sorry, please forgive me I must be lost. Your saying you don’t have check valve internals on your downstream injector but you can close the flow all while not filling your chemical tank with water coming OUT of the chemical inlet of your injector?

I’m very interested in this conversation. The last time my injector spring broke it half filled my SH tank with water and ruined the batch.

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No worries at all. Yeah that’s what I’m saying. My DS injector has no internals and I’ve never had an issue with backfilling into my chem tank. However, now that you’ve brought it to my attention I think that it may be backfilling, but it’s just not enough for me to notice. This is because I have a 2-way valve for my injector that I switch between water and SH since it constantly draws. So my injector is hardly ever switched to the SH side, and when it is switched to the SH side I’m on the trigger 90%+ of the time to spray soap, and then quickly switch it back to water to rinse. Now that I think about it, the only time I really lay off the trigger is when it’s switched to the water side if I have a break between rinsing. So it could very well be backfilling water, but I’m just not noticing since it’s going back into my water tank. And when it is backfilling into my chem tank, it’s for such a short period of time that I hardly notice and it barely dilutes my SH. But still I’ve never noticed a problem with it. I’ll begin to keep an eye out for it though. I appreciate you bringing it to my attention

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@dcbrock My thoughts exactly

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I did a draw test and my SH side is pulling wayyyy slower than my water side. I set both lines in a 5 gal bucket and the water side of my proportion drained super fast while my SH side was barely draining. What should my next step be? Disassemble the metering valve on the SH side and see if pulling straight off the check valve fixes it? Because then if pulling straight off the check valve doesn’t work I know it’s likely the check valve that’s broken, and if it does work then I know it’s likely the metering valve that’s broken

Were the hose length and diameter the same between the water and chem tanks during your test? And are you using a filter on the pickup hoses? It’s possible you sucked something up that’s now clogging the line. From what I’ve read, check valves tend to fail more often than metering valves. I’d suggest taking apart the chem side… you might luck out and just find debris caught somewhere in the line, and that alone could be the issue. Even if it’s a failed part, disassembling it should give you a much clearer picture. Also, check the SH pickup line for any air leaks, and make sure the container vent is open to prevent vacuum lock.

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Make sure the cheap check valve is oriented the proper direction, there’s usually an arrow on the side.

That being said I got fed up with those and got a Hayward ball check valve that doesn’t have a spring

I have my downstream injector on a remote ball valve so I can turn it off and off when I’m behind a house. If I take out the ball and spong would I get more flow of chemicals from the tanks? The water would then only back up until it hits the remote ball valve correct?

Thank you

Not having a check valve IS leaving a door way open

Disregard I’m unclear on what you have equipment wise. PM your number and we can discuss it