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Adding Low Pressure Presoak System Questions - SS

trs246810

Member
I'm finally adding presoak. Are there any problems with delivering it to each bay through the tire cleaner supply line? (sharing the line) Would there be any problems with back pressure on the closed solenoids of whichever product isn't in use at the time? Could the potential for problems be eliminated with where I place low pressure check valves?...OR, am I making this way too difficult...and just needing to run a separate supply line for presoak out to each boom? Also, I do plan to setup another solenoid manifold in order to add air to the product for foaming...any recommendations on that would also be greatly appreciated?
 
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Delivery switchover will take a while if they share the same line. My PS and TC use different lines to the same manifold above the bay.
 
Whether or not you have backflow from one system to another depends on the pump you're using. I run FloJet pumps dead-headed (No control to the pump, it's always pressurized) so there's no place for backflow to go. If you use an electric rotary vane or centrifugal pump, you need a check valve somewhere or you will get backflow. I would put a single low-pressure valve on the outlet of the pump to insure it doesn't run with no supply if the valve fails closed.

I wouldn't try to run tire cleaner and presoak through the same line.
 
As Mep said, if you're using Flow jets, no cv's needed for backflow. But depending on where the regulators are located on the air side, you may or may not need cv's.

Another option....put both ps and tc on a separate boom/gun. I have ps and tri foam on a separate boom/gun. It's a heck of a lot easier to push product and air through a 4040 nozzle than it is an 06 tip! Plus the ps foams a lot better running it through a foamer. Customers love it. It's one of the best things I did at the wash. It allowed me to get rid of 12 cv's on the hp manifold above the bays. That's just for a 4 bay.
 
This is all giving me a lot to think about. It will be a procon pump. I'm definitely leaning towards running the presoak through its own supply line now. Are there any thoughts on how/where to have the air and product mix for presoak? I'm asking for presoak...as well as tire cleaner? I'd like both to go on foamy...and I might as well work on accomplishing both during the presoak install. I did the DIY foam generators above each bay for my foamy brush, but that's all I have foaming with air now. I do kinda like the idea of a separate gun at some point further down the road. Thank you all for your advice.
 
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I'm with Earl, using a common air line and one check valve at the bay really reduces problems, and using an air regulator that has a bleed-off for excess downstream pressure will protect your lines from bursting if the check valve at the boom fails.
 
Video of air added above the bay. Just T'd in to the manifold where the PS and TC lines go. Both TC and PS open the air solenoid when that function is chosen. No foamers, no needle valves.]

Earl
What kind of pump are you using for your TC?
What pressures are you running on the pump and on the air?
 
I like that idea...and thanks for the video. That looks like what I'm trying to achieve.

I tried duplicating what Earl posted in the video on the hp gun. Couldn't do it. Moving ps to the foam gun and running it through the foamer worked right out of the box.

Whatever direction you decide to go, don't skimp on the poly tubing. Use 3/8 instead of 1/4 inch. You will get about 6 times less pressure drop using the 3/8.
 
Earl
What kind of pump are you using for your TC?
What pressures are you running on the pump and on the air?

All low pressure functions are flo jets. 1 Pump handles 8 Bays, except foam Brush I use 2. TC Flo Jet is at 40 PSI and Air is at 20. I use 3/8" poly lines. to the manifold above the bay. Seems to be enough mixing from there to the Gun Tip or FB to make foam without any other generators needed.
 
I tried duplicating what Earl posted in the video on the hp gun. Couldn't do it. Moving ps to the foam gun .

My guess would be tip size issue. Not sure what mine is. I think it's a 1505. If you try to force foam thru a small opening the foam gets killed. In that situation less can be more ... Less volume - psi to the iar and flo jet can = more foam.
 
Would you say 3/8" on air, and 1/4" on the supplies would still be okay ? It's just a 3 bay. I might as well ask if 1/3 or 1/2 HP procon matters? I will experiment with one air line feeding the TC and PS. It will take me a second to think about jumping the wiring so the solenoids for air open for both product selections. Yes, that makes me a little slow...and shows why I've gone so long without presoak. lol I'll also be going with an IDX MX-10 for the PS. I'm committed to making this happen though. I can't work on it until next week, but I'm getting things laid out for it. I'll definitely let you all know how things come together. I can't see my questions about it all ending quite yet.
 
There are online calculators that will tell you how much pressure loss you will have between 1/4" and 3/8" for a given length. It is significant. I'm going off memory...For a 50' run you have about a 5 psi drop with 3/8"....about 30 psi drop with 1/4".

Initially, I used 1/4" on ps....Even on the foam gun it was not satisfactory. Switching to 3/8" made a huge difference.

If you use 1 air solenoid per bay for both ps and tc, you will have to use relays to energize it. Jumping air solenoids together will energize both ps and tc chemical solenoids.

You can still run 1 air hose to the bay if you have separate ps and tc air solenoids. Just tee the output off both air solenoids inside the er to the single hose to the bay. Using John Guest or SMC push to connect fittings makes it easy and extremely effective.
 
My guess would be tip size issue. Not sure what mine is. I think it's a 1505. If you try to force foam thru a small opening the foam gets killed. In that situation less can be more ... Less volume - psi to the iar and flo jet can = more foam.

My tips are 2506, larger than your 1505's...still couldn't duplicate it till I moved ps to the foam gun and ran it through a foamer. 3/8 poly tubing helped a bunch too.
 
Good thread, I am thinking about adding air to my PS. Currently I only have PS, and when TC is selected on the dial, PS comes out. No complaints, but I have been thinking about adding real TC and then adding air to both that and my PS. Just think it would be nicer. Doesn't seem like it is a big project either.
 
I use 1/4" for air and tire cleaner, 3/8" for presoak. The longest run is a bit over 100', and there's no noticeable difference in pressure from the closest to farthest bay from the equipment room. I keep the tire cleaner restricted quite a bit with needle valves, presoak has none.
 
There are online calculators that will tell you how much pressure loss you will have between 1/4" and 3/8" for a given length. It is significant. I'm going off memory...For a 50' run you have about a 5 psi drop with 3/8"....about 30 psi drop with 1/4".

To back up this statement.....Here is one of the best online pressure drop calculators I could find...

http://irrigation.wsu.edu/Content/Calculators/General/Pipeline-Pressure-Loss.php

1/4" poly tubing with an ID of .170" looses over 30 psi in a 50' run when pushing .5 gpm through it. If you're only pushing .25 gpm through it, pressure loss is a lot less. The program allows you to get a quick comparison in PSI drop when you have a fixed volume. In this case, when comparing 1/4" and 3/8" regardless of volume, pressure loss is about 6 times higher using 1/4" over 3/8".
 
To back up this statement.....Here is one of the best online pressure drop calculators I could find...

http://irrigation.wsu.edu/Content/Calculators/General/Pipeline-Pressure-Loss.php

1/4" poly tubing with an ID of .170" looses over 30 psi in a 50' run when pushing .5 gpm through it. If you're only pushing .25 gpm through it, pressure loss is a lot less. The program allows you to get a quick comparison in PSI drop when you have a fixed volume. In this case, when comparing 1/4" and 3/8" regardless of volume, pressure loss is about 6 times higher using 1/4" over 3/8".

Thanks 2Biz for taking the time to find that worthwhile very useful calculator.

I bookmarked that webpage as it is seems like a good reference & good information.

mike walsh www.kingkoin.com
 
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