Genius? or Dumb Super Wash Setup

[OurTown]

We are trying to get our three self serve bays back up and running after an insane remodel and it has been a struggle. Almost everything was torn out and put back in a different spot. I wanted to make sure the pumps were still good after sitting all those months so I hooked up the city water and jumped the solenoid valve and motor starter on bay 1. (we don't have the meter boxes wired yet) The hot water gravity tank is not hooked up yet. The pump started out fine but chattered and lost pressure when pulling the trigger in the bay. It acted like it was starving for water so I pulled the mesh strainer near the pump inlet to check for volume. It was only getting about 2.5 GPM and with our tip and pressure setting it would need 3.5 GPM minimum. I tested the other two bays for volume and they were a little better but nothing over 3 GPM. I pulled the plunger out of the solenoid valve and got maybe 3.2 GPM out of one. Also, I pulled all the plumbing off the solenoid valve all the way past the mesh strainer and didn't see any issues. The feed line to the solenoid valve is a 3/8" OD poly tube and when removed tested about 5+ GPM. The GC valve is only a 1/4" with a 3/16" orifice and I thought that seemed small. At that point, I was really confused about why Super Wash built it that way and could not understand how it could have operated properly all those years. I decided at that time that I was smarter and would buy larger 3/8" solenoid valves with 9/32" orifices and replumb all the 1/4" fittings to all 3/8". Today I got the valves and fitting so I redid bay 3, turned on only the solenoid valve, and was happy that I was getting about 4.4 GPM past the mesh strainer. There was water all over the floor and I tracked it down to the gravity tank inlet so that check valve is bad. I checked the other two and one of them is bad too but I don't remember before having the gravity tank level rise when someone was on rinse. Then I thought about how it may have worked before. The solenoid valve is a little undersized and the pump draws the extra water it needs from the gravity tank. If the check valve leaks a little, it will not back up into the gravity tank and may never need to be replaced. Are they the geniuses and I am dumb for re-engineering it?

 

[OurTown]

 

[OurTown]

 

[OurTown]

Also, would like a recommendation on whether to go with a poppet or piston style check valve.

 

[OurTown]

Will these work well with gravity pressure?

https://www.carwashsuperstore.com/smc-brass-3-4-fpt-x-fpt-piston-check-valve-with-viton-o-ring

 

[2Biz]

In my opinion, most Carwash Engineers missed the K.I.S.S. method during the engineering phase. It seems they were more focused on making it so difficult that no-one could figure out how to work on it except their trained service techs!! I re-engineered my 'ol Mark VII pumpstand and have absolutely no regrets.

Sorry, can't help with your flow issues or CV needed....My system is gravity fed hot/cold water...I contemplated a city pressure fed pump and gravity hot water during the redesign, but glad I kept gravity tanks for both Hot/Cold water. The only CV needed is to keep weep from backfeeding into the tanks, and its on the HP side of the pump...

BTW, I bought a dozen or so rebuildable 3/8" SS Rego's a few years ago...I believe they were in the $30 ea range...I just saw on CWSS they are now $108! Wow! Glad I bought at the time I did!

 

[OurTown]

This one specifically states it is used for tank and inlet applications and has zero cracking pressure:

https://www.kleen-ritecorp.com/p-3260-kleen-rite-944-431-brass-inline-check-valve-3-4in-f-x-f.aspx

 

[Greg Pack]

That setup might have been necessary to draw enough soap product through too if the soap was highly diluted.. I think a excessive water starvation might contribute to shortened seal life and premature head washout. I run my SS soap and wax tanks very strong and avoid throttling back my water supply unless absolutely necessary. So in my mind your design is an improvement.

 

[Randy]

The system we use is absolutely butt simple, no gravity tanks, no overflowing water tanks to deal with. I’ve got 2 hoses coming in 1 hot and 1 cold, they go into a high flow Generant regulator, this reduces the city water pressure down to about 15 psi or so and on into a DEMA 203C injector and into the pump. I’ve got 2 - ½” DEMA solenoid valves for the incoming water and 2 – ¼” KIP solenoid valves for soap and wax. It doesn’t get much simpler than that. Very seldom do I ever have any problems with the pumping equipment. No head wash out, seals last longer because your not starving the pump for water.