Soap tank overfilling

[MEP001]

This one has me stumped. Three compartment tank with water, soap, and wax. If I watch it long enough I can see the tank filling, even when no one is using a bay, and it's diluting the soap. Here's what I'm sure it's not:

It's not the Hydrominder. No drips before the valve, and I take the discharge hose off every day and watch for it leaking.

It's not a leak between compartments. It's three separate tanks welded together at the top and tack welded at the bottom.

It's not rinse backing up through a check valve. I only have cold water anyway, and there were so many breaks from the recent freeze to the line that fed the rinse solenoids that I took the whole 14 foot line out and capped it.

It's not spot free backing up through the pump. Three separate times I have turned on either one bay at a time or all bays at once on spot free and disconnected the tubing from the soap solenoid to check for backflow. The spot free solenoids don't leak by to other bays when on or at all when it's not running.

It's not the soap solenoids. I have them plumbed backwards so I don't have to have a check valve on the soap and wax lines. There's no sign of soap with rinse selected on any bay. If I unhook the soap tubing from the tank when it's on rinse, it doesn't draw air through the solenoid.

It's obviously not siphoning from the soap concentrate.

I'm sure I've eliminated every possibility, but every day I have to dump some soap in the tank to bring it back up to strength.

 

[Dan kamsickas]

When you see it slowly filling the tank, systematically shut off the ball valves under the tank to isolate which bay.

Does the system still have a weep system connected? It could have ball valves and/or solenoids leaking water through a questionable soap solenoid.

 

[PaulLovesJamie]

... I'm sure I've eliminated every possibility, but ...

I can relate to that, lol. For me it's air getting into the pumps.

Since its only the soap tank, I'd put a kit in the solenoid and hydrominder. Even though I know they're good, those are the 2 closest points of entry for water so I'd want a second level of confidence that those possibilities are eliminated.

 

[JGinther]

If I understood it right, you have removed the pressurized cold water rinse feed option and only have gravity rinse from a tank?

No weep system is installed since it wasn't mentioned?

Does the hydrominder chain slack up over time, or does the soap only lean down? Does the tank ever overflow to drain or does it stop mystery filling after a certain point/level is reached?

 

[MEP001]

Does the system still have a weep system connected? It could have ball valves and/or solenoids leaking water through a questionable soap solenoid.

Since its only the soap tank, I'd put a kit in the solenoid and hydrominder.

I'm certain it's not the soap solenoids. I've checked them all several times. I'm certain it's not the Hydrominder. I've checked it every day for two weeks.

 

[MEP001]

If I understood it right, you have removed the pressurized cold water rinse feed option and only have gravity rinse from a tank?

Right.

No weep system is installed since it wasn't mentioned?

Correct, I forgot to mention it, but it was on the same line as the rinse solenoids.

Does the hydrominder chain slack up over time, or does the soap only lean down?

The chain does grow slack.

Does the tank ever overflow to drain or does it stop mystery filling after a certain point/level is reached?

I haven't seen it overfill. I'll put something under the tank tonight so I'll catch it if it does.

 

[OurTown]

It's probably a ghost.

 

[MEP001]

It's probably a ghost.

They only mess with electrical.

 

[2Biz]

I had a soap solenoid that was allowing backflow from the gravity feed water tank into the soap tank. Drove me nuts till I figured it out. Every bay was affected the same, took forever for the first wash of the day to get soap to the pumps and bays...Turned out to be the furthest bay away in line so all bays were affected the same. But before I rebuilt the pump stand, you couldn't see the soap in the hoses up to the pump....Now I have clear LLDPE tube on all LP chemical lines where I can see if something is diluting. It would always backflow till the gravity tank and soap tank were the same level...Do you have clear soap hoses to the pump so you can see if the soap in the lines is getting diluted? That way you can positively rule out a soap solenoid!

 

[JGinther]

Thanks for typing all of that 2biz.

Wondering if it's possible the solenoid tests are disproving themselves by sealing under pump vacuum, but not under an idle situation... And maybe just a really really slow leak at that. (This seems not likely though, since the solenoids are backward). Otherwise, I can confirm it's not broken if that makes you feel better?

 

[MEP001]

I'm fixing to replumb it and planned on using natural tubing (It's mostly red now with some black 'cuz that's what I carry). If there is anything backing up, I can't tell. I've unhooked the tubing many times to check for any backflow and can't find anything, and there's no sign of soap on rinse so if it is a solenoid leaking it's an incredibly small amount. I've opened them all and they look fine, but I'm going to move them to a tree with new solenoids mounted on the wall next to the stand.

I can't tell that any bay takes longer than it should to get soap, but sometimes I notice a bay will have normal strong soap for a couple seconds before it gets weak.

Do you have clear soap hoses to the pump so you can see if the soap in the lines is getting diluted? That way you can positively rule out a soap solenoid!

My soap is clear, but I could drain the clear water tank, put some foam brush soap in the opening and let the tank fill back up. Might do that next time I'm there late at night (which is often).

 

[MEP001]

Wondering if it's possible the solenoid tests are disproving themselves by sealing under pump vacuum, but not under an idle situation...

I don't have to throttle the water to make the pumps draw soap, but maybe if I do that and there's a solenoid slightly leaking through I'll see soap with rinse selected on that bay.

 

[2Biz]

but sometimes I notice a bay will have normal strong soap for a couple seconds before it gets weak.

The tell-tell sign it's an upstream solenoid backfeeding from the gravity tank.

 

[MEP001]

The tell-tell sign it's an upstream solenoid backfeeding from the gravity tank.

I figured that was because it's weak in the tank already, but that bay at the time has soap in the lines that's from before the tank got diluted.

If it does turn out to be a solenoid I'll never figure it out, because I'm just going to replace them all. I haven't had a spare minute to even look at it the last couple days.

 

[MEP001]

Whatever this was, it has self-corrected. I haven't had any issues in the last five or six days.