No water in ss

[Jimmy Buffett]

I have 3 ss bays with a JC pump bench. All 3 bays are shutting down at the same time and then for no reason start back working again. I have had this happen before when there was no water in the holding tank but that is not the case now. It seems like they are starving for water but what would affect all three bays at the same time if the tank has water in it?
Thx

 

[Washmee]

Faulty water level sensor in the holding tank?

 

[Jimmy Buffett]

I run my reject water into this tank. If the autos are busy and the ss is not sometimes the tank overflows and the float valve will get wrapped around something and the tank will run dry. When my employee called today I was sure that was the problem but the tank has plenty of water in it. I just got to the wash and of course I can't make it happen so I can't even see the problem. It happened twice this morning though.

 

[MEP001]

You've probably got air from a low pressure system backing up through a pump and into the hot water lines. Easiest way to tell if a check valve is bad is to run all three bays on soap until the valves get hot, then turn them all to rinse. The bad one will get cold.

 

[cwguy.com]

Change your float valve to that yellow one (really helpful.... but I love them.... whatever their name is). Or drill another hole in the tank?

 

[JGinther]

Any chance the water stream from the fill valve or the reject is false tripping the level switch? Otherwise its the switch, relay to the plc, or the wiring in between.

 

[cwguy.com]

If the tank has water and the hp pump is cutting on there is not a problem with the switch, plc or wiring..... or the pump would not cut on. There has to be something else going on like mep1 suggested. Air would cause the results described. Checking every lp function in every bay while running the hp pump in a bay could also replicate the problem.

But you could easily test your theory if you wanted.... but I would think that problem would be more intermittent? Or even constant?

 

[Jimmy Buffett]

You've probably got air from a low pressure system backing up through a pump and into the hot water lines. Easiest way to tell if a check valve is bad is to run all three bays on soap until the valves get hot, then turn them all to rinse. The bad one will get cold.

Well I know this is going to sound stupid because it is stupid, but how do I identify the check valves?
I keep the chain pretty long on the float valve because I like to use as much of the waste water as possible. I have very good auto business but my ss is mediocre at best so it is not unusual for the tank to overflow. Is it possible that that level is suddenly not high enough after all these years? It always covers the outlets but does it need more than that?
Thanks

 

[DiamondWash]

Jimmy,

I had the same issue before and it turned out to be the low level switch in the holding tank, caused hell with the customers and on the equipment on off on off on off replaced it and no more problem.

 

[JGinther]

The coleman racks actually have nothing in common between each of the pumps except the low level switch and the tank itself. Maybe CWGuy didn't understand what I meant, but I would check to make sure that the water stream filling into the tank isn't flowing by the switch rapidly and making the switch false trip. I would just wire around the switch temporarily and see.

 

[MEP001]

Well I know this is going to sound stupid because it is stupid, but how do I identify the check valves?

On the standard Coleman equipment, they're on the manifold at the back of the tank screwed into the tank outlets. The rinse solenoids will tee into the same manifold after the check valve.

 

[Jimmy Buffett]

I can't make it do it again. I think I will shorten the chain by a couple of inches today and then go from there. Behind my pump bench there is not much room for a fat boy like me! Thanks

 

[cwguy.com]

Check valves like to stick intermittently so that might still be your issue.

Also mep1 is referring to under the pumping station not behind.