How much PSI?

[Indiana Wash]

OK, I have had my car wash for 7 years and replaced or worked on about every part. Now, for the first time, I have a bad unloader. How do I know how much psi I have my pump running at? How do I set the unloader? How do I make sure nothing is set so high it is going to strip paint? Thank you.

 

[MEP001]

How do I know how much psi I have my pump running at?

I'm guessing you don't have gauges on them? That's the only way I know of to tell the pressure.

How do I set the unloader?

Unloaders either have a big plastic handle or a spring with a nut on top. You would tighten the handle or nut to increase the pressure. If you don't have either of those, you probably don't have an unloader.

How do I make sure nothing is set so high it is going to strip paint?

As a rule, car wash pressure won't "strip paint" unless it's already about to come off. Car washes are usually set anywhere from 800 to 1600 PSI. I wouldn't ever go higher than that, more for risk of injury than paint damage.

 

[2Biz]

Mep pretty much covered it, but if you'd post a picture or tell us which regulator/unloader you use, it would be much easier to give you a precise answer. Here's the unloader I use:

https://www.kleen-ritecorp.com/p-1961-giant-adjustable-unloader-1400-psi-13-gpm-yellow-springs.aspx

My Unloaders have multiple 1/4" NPT ports on them for pressure gages. It your regulator/unloader doesn't have the added ports, you can put a "Tee" between the regulator and HP hose to mount your pressure gage. Make sure you use an oil filled gage. It helps dampen the spike of the higher pressure and will make it last longer.

 

[PaulLovesJamie]

as MEP001 said:

I'm guessing you don't have gauges on them? That's the only way I know of to tell the pressure.

iirc, the very first change I made after buying my wash was to add gauges to the high pressure side of the pump.
Also, remember that the pressure in the bay will be lower than at the pump head, so you want to decide what pressure you want at the bay and measure it there.
To measure pressure in the bays, I put a spare gauge on a brass T with a spray tip. Screw it into gun/wand and run the bay to see what pressure the customer actually sees. Also NB that longer runs to further bays will lose more pressure than the nearer bays, so not all pumps will have the exact same pressure...

 

[2Biz]

Measuring at the unloader, I run 1200 psi for 3 bays and 1500 to the furthest bay (3 bays from the ER), my outside bay. There is no real noticeable difference (That I can tell with the 300 psi difference) unless its because of the added 15 feet or so. If you want to get it exact, set it like Paul suggests. But you still need gages for reference in the ER to see if the regulators are working correctly or not. That is once you get your baseline...

 

[MEP001]

On a short run the pressure difference at the gun will be minimal. The longest bay is nearly 100' of hose so I have the pump running at 1500 PSI to keep 1200 at the gun.

 

[tdlconceptsllc]

You don't need to do all that extra work like putting a pressure gauge in the bay at the end of the wand???? Guys its so simple it will hurt your mind lol. Have someone SQUEEZE the trigger gun in the bay while a technician is in the equipment room looking at the pump station and the pressure gauge set the Unloader with a adjustable wrench +or- while someone is squeezing the trigger, If you are by yourself use tape to wrap around the trigger gun. Everyone I know does this method. Will save you so much time 2mins or less.
1,200psi is a plenty. Hope this helps.



https://www.facebook.com/pages/Southern-Pride-Carwash/231647943556095

 

[Randy]

You don't need to do all that extra work like putting a pressure gauge in the bay at the end of the wand???? Guys its so simple it will hurt your mind lol. Have someone SQUEEZE the trigger gun in the bay while a technician is in the equipment room looking at the pump station and the pressure gauge set the Unloader with a adjustable wrench +or- while someone is squeezing the trigger, If you are by yourself use tape to wrap around the trigger gun. Everyone I know does this method. Will save you so much time 2mins or less.
1,200psi is a plenty. Hope this helps. That's the way I'd do it. Only p...h" doesn't have any gauges on his pump stand.

 

[MEP001]

I use the Hamel stainless channel mat clamps and Giant weep guns, and it's a perfect fit to rest the trigger of the gun on top of the mat clamp to hold the gun open.

If you're adjusting the pressure with the trigger pulled, DON'T tighten the adjustment any more than what will let the pressure increase. I can't tell you how many times someone has tied off the gun in the bay and went inside and kept cranking on the regulator trying to get the pressure higher, then went out and released the trigger. The reduced flow will cause the pressure to spike and blow the line or damage the pump, or worse cause a customer to be injured by the pressure.

 

[PaulLovesJamie]

You don't need to do all that extra work like putting a pressure gauge in the bay at the end of the wand???? Guys its so simple it will hurt your mind lol. Have someone SQUEEZE the trigger gun
...

I've been called dense many times (mostly by females!) but I am in fact sharp enough figure out how to pull the trigger to read a pump stand pressure gauge, as I suspect most of us are.

 

[PaulLovesJamie]

In case the OP (or anyone else) cares, I'll try to clarify my post because I think it is important, I think most of you guys are looking at this backwards.

From a customer perspective, what are the 3 most important characteristics of a SSSCW? For the sake of argument lets say reliability cleanliness pressure and soap. OK maybe its 2 things, maybe its 4 or 5, but I think most of us would agree that "pressure" is on the short list. If so, then precisely why would you not want to know exactly what pressure your customer experiences? IMO we only have gauges in the ER because its impractical to install them on the gun/wand! From a business perspective I dont care what the pressure is at the pump stand, I consider pressure to be part of the product I'm delivering to the customer and therefore I measure it at that point - where I do in fact deliver the product to the customer, ie in the bay. I do have gauges at my pumps, and I do glance at them daily; but to me they are an operational indicator, nothing more.

You may laugh, but I have seriously thought about mounting a pressure gauge on my booms, both for me to monitor and also for marketing & differentiation purposes. 10 years or so ago I even looked for a gauge with an unbreakable faceplate. (Didnt find one, maybe I should look again!) I cant even count how many customers comment on the good pressure as compared to my competitors.

If you dont care too much exactly what pressure your customer is experiencing, or about variation among your bays, or how your experience differs compared to your competitors, then by all means dont waste the time to check the pressure in the bay! If thats the case, then you & I simply disagree.

I'll also point out that screwing together a street T with a pressure gauge and a spray tip takes all of 4 or 5 minutes, then its done forever. Screwing it into a gun/wand to test a bay's pressure takes another 3 or 4 minutes, I do that after I work on a pump. Maybe I check one bay a year - 5 minutes is not "all that extra work," especially for what I do consider to be among the most important features my customers care about.

Btw, to get the same pressure in each bay at my wash, there is a difference of a couple hundred psi of pressure between a few of my pumps. Yes, a couple hundred. Perhaps your pressures are identical and this is all a humorous diversion... but if you dont measure it you are speculating, you dont really know.

 

[Greg Pack]

I use the "Tee on the end of a wand" method to get a reading. That way I can say with a great deal of confidence to a customer that the pressure is the same at the nozzle tip in each bay, regardless of distance form the pump room. While making this adjustment, I mark the pressure gauges in the equipment room with a fine tip sharpie. In the future I use this mark on my pressure gauge to monitor/adjust the pressure.

 

[MEP001]

I use the "Tee on the end of a wand" method to get a reading. That way I can say with a great deal of confidence to a customer that the pressure is the same at the nozzle tip in each bay, regardless of distance form the pump room. While making this adjustment, I mark the pressure gauges in the equipment room with a fine tip sharpie. In the future I use this mark on my pressure gauge to monitor/adjust the pressure.

I do basically the same thing, except the two end bays with the longest hoses are running 200 PSI higher to help speed the changeover time. I put a quick-connect right below the swivel saver on every bay, and at one time I had a gun with a gauge on it for checking the pressures, though I dismantled it for the parts some time ago.