Foam brush function

[Sudsz]

Hi folks! I am a newbie here, working on and old car wash, so go easy on me... haha. I am working with a D/H system, and the issue is with the foam brush operation.
I power it up
turn to foam brush
Air only comes out of the brush
Psi gauge reads ~5psi
Motor does not kick on
Force in manual and it kicks on (may. cycle on off a couple times or once)
Psi goes up to ~55 then stops the. pump

Faulty Psi switch???

Thanks in advance for any help!

 

[MEP001]

It sounds like things are mostly working like they should. The switch could be failing (It should kick on when the liquid pressure drops to about 35 PSI). You may have the air pressure too high and it's forcing its way back through the liquid line and not letting the switch activate. D/H used steel fittings on the hose that runs through the boom and it will rust closed inside. Someone probably cranked the air pressure way up to try and get flow. See if you can get the flare fittings on both ends loose and run a drill bit through it to get it clear, then you can turn the air pressure down to about 20 PSI where it should be.

You might eventually want to change it to a Flojet pump which will eliminate everything but the liquid tank.

 

[Sudsz]

It sounds like things are mostly working like they should. The switch could be failing (It should kick on when the liquid pressure drops to about 35 PSI). You may have the air pressure too high and it's forcing its way back through the liquid line and not letting the switch activate. D/H used steel fittings on the hose that runs through the boom and it will rust closed inside. Someone probably cranked the air pressure way up to try and get flow. See if you can get the flare fittings on both ends loose and run a drill bit through it to get it clear, then you can turn the air pressure down to about 20 PSI where it should be.

You might eventually want to change it to a Flojet pump which will eliminate everything but the liquid tank.

Awesome thanks! I will give that a shot!

 

[Sudsz]

It sounds like things are mostly working like they should. The switch could be failing (It should kick on when the liquid pressure drops to about 35 PSI). You may have the air pressure too high and it's forcing its way back through the liquid line and not letting the switch activate. D/H used steel fittings on the hose that runs through the boom and it will rust closed inside. Someone probably cranked the air pressure way up to try and get flow. See if you can get the flare fittings on both ends loose and run a drill bit through it to get it clear, then you can turn the air pressure down to about 20 PSI where it should be.

You might eventually want to change it to a Flojet pump which will eliminate everything but the liquid tank.

Made some adjustments and got the foam pressure switch to operate on it's own. However when the timer runs out, it still continues to operate.

 

[Randy]

I haven't seen one of those setups for years. You've got a bad pressure switch. The best thing you can do is to replace the pressure switch with a IDX MX-8 multiplexer https://www.kleen-ritecorp.com/p-24000-idx-mx8-controller.aspx or build a bank of relays to stop and start the pump. Or install a Flojet pump.

 

[MEP001]

Made some adjustments and got the foam pressure switch to operate on it's own. However when the timer runs out, it still continues to operate.

There is a check valve between the bladder tank and the reservoir that's probably bad. IMO you'd still be better off replacing the whole mess with a Flojet pump. It's a good idea to have something in place to stop air flow to the pump so you don't waste a bucket of soap overnight if a solenoid sticks, but it's not 100% necessary.