Chemical Tee Manifold advise

[DiamondWash]

I am helping another wash owner replacing all of this HP lines from the pump to the tee manifold in other words up in the attic, he wants to eliminate the "HP line Fluid Control Free Flow Check Valve" seen in this picture thinking it's restricting the pressure and giving him false readings on the gauge on the pump. It would make sense to have that there so LP functions don't backfeed, am I wrong on this reason?.

 

[MEP001]

It depends on how his high pressure pumps are plumbed, and how well he maintains them. I've seen big issues with tire cleaner/presoak backing up into the tank on a wash where the pumps weren't maintained and with no check valves on the inlet from the tank. If there are check valves inside there should be no issues unless the LP is higher than the city pressure, then it can back up into the rinse solenoid. The spot-free being even higher will be a bigger problem. I'm very tight on pump maintenance and have no issues with anything backing up into the lines - I occasionally run low pressure/spot free back and forth a few times for a couple minutes, then purge the bay hose with spot free and finally go to rinse, and there's not a burst of tire cleaner that's backed up into the HP line. I don't use a check valve on the HP line.

If he's concerned, maybe go up to a 1/2" check valve. I'd recommend the one with a Teflon seat - I've had the Buna-N rings come off.

I don't see a check valve on the spot free or tire cleaner lines unless it's a 1/4 x 1/4" male one.

Looks like a Coleman setup, or a copy of their style.

 

[DiamondWash]

No check valves in the equipment room once it leaves the pump it's on up to here in the attic. I took off the HP Line check valve which is a free flow style from Fluid Controls and what concerns me is this set screw which should be stainless could break and get lodged causing the check valve to not function.

 

[MEP001]

Yeah, that screw should be stainless. The ones I have appear to be. I have seen chemicals do that to stainless, mainly Stinger products. I filled one with brine to let sit overnight.

I used a 1/4" Fluid Controls valve on the spot free which runs at 450 PSI, and it broke the plastic tabs off so the rest of the check assembly got wedged in the nipple on the outlet side. That's another reason to go oversize.

 

[JGinther]

I prefer having the check valve in the equipment room - because then it isn't on the roof. I always tie the weep and the check valve referenced at a tee on the pumpstation. I never use tank checks because I prefer to waste energy and always use hot water. If my customers were smarter, I wouldn't do that... But they're not, so I do. Its also nice to not have tank checks because suction on soap and wax have nothing to do with the amount of crack pressure that a check valve has.

 

[MEP001]

The valve I filled with brine yesterday still looks completely clean this morning.

 

[DiamondWash]

Since I removed the check valve on the high pressure line at the tee he said there is more pressure at the gun then before, my question is would you leave the check valve off the HP line or just install a new check valve?. And yes the SPR has a silver 1/4"x1/4" CV and the Tire Cleaner has a brass 3/8" CV at this tee.

 

[MEP001]

I really don't like unnecessary check valves. I can't tell you how many washes I've been in where they had a problem somewhere, so their solution was to add a check valve. Tire cleaner coming back through the air line and weeping out the regulator? Don't bother adjusting the air pressure up where it should be, just add a check valve before the regulator and watch the lines blow when a check valve at the boom fails. Spot free tank contaminated? Don't bother checking the ones in the bay, just add one at the tank so the service cap on your Procon pump swells like a loaf of bread baking and it no longer works. Adding check valves when there's a problem doesn't solve the problem, it just masks it and adds yet another failure point.

If the wash has tanks for soap, wax, and hot water, with a city pressure rinse solenoid for cold, I either use one check valve with soap, wax and hot water behind it, or I use one just on hot water and turn the soap and wax solenoids around so they act as their own check valves. If you both decide a check valve on the high pressure line is necessary, I'd put it at the pump and not the boom, and I'd use at least one size larger than the pipe fittings.

 

[Greg Pack]

Why does he need a check valve on the HP line? I never run one on mine.

BTW, you can check your pressure at the nozzle by building a Tee to temporarily install at the end of your wand. Put a nozzle on one port and a pressure gauge at the other. Screw this in at the end of your wand. You can then adjust the pressure to your setting. For example, to get 1000 at the nozzle I have to set the pump so the pump gauge reads around 1300. I then mark the pump gauge with a sharpie so I know where it needs to be set to give me 1000 psi at the nozzle. This eliminates all guesswork and ensures consistent pressure in each bay.

 

[MEP001]

I do the same, you have different amounts of line loss for different lengths of hose to the bay as well as the gauges themselves not being very precise. Once I set the pressure at the bay with the gauge on the gun I mark the gauge in the room so I don't need to reassemble a gauge on a gun again if I have to change something.

 

[2Biz]

Why does he need a check valve on the HP line? I never run one on mine.

Shouldn't need one above the bay as long as you have a CV at the pump to keep weep and P.S. from back feeding.

 

[DiamondWash]

I decided to remove the check valve from the HP line on the other bays as well. Like Mep001 said one less failure point to maintain.

 

[Randy]

That would probably be a good idea. I've never put a check valve in the high pressure line. I don't know why you need one on the high pressure line.

 

[CleanMachine]

Do i need a check valve on air AND chemical on low pressure functions? (Foam brush, tire cleaner, tri-foam) Thinking of using John Guest 1/4 x 1/4 pushlock check valve on 1/4 inch lines. In equipment room? OR closer to 1/4-3/8 TEE above bay?
THANKS!

 

[DRsuds]

Would having a check valve on the high pressure at the T make the spot free and tire cleaner delivery faster? Since it wouldn’t have to fill the HP line before coming out of the gun?

 

[MEP001]

Would having a check valve on the high pressure at the T make the spot free and tire cleaner delivery faster? Since it wouldn’t have to fill the HP line before coming out of the gun?

If everything is working right, there's no need for a check valve on the high-pressure line. It should stay full of water and not allow anything back into it so it doesn't need to fill.

 

[Greg Pack]

There is some pressure/volume loss in those tiny orifice MXM check valves. I prefer the larger orifice in the FXF check valves.

 

[DRsuds]

If everything is working right, there's no need for a check valve on the high-pressure line. It should stay full of water and not allow anything back into it so it doesn't need to fill.

Even if I have weep guns? Wouldn't water escape from the gun?

 

[MEP001]

Even if I have weep guns? Wouldn't water escape from the gun?

Not unless your pumps are bad and your gravity tanks are a lot higher than the guns.