Water pressure and the effect(s) it may have on rotary pump

[dk]

Water pressure and the effect(s) it may have on rotary pump of a direct connect machine. I am a brand new owner of a Vetrano and I have not measured my water pressure and I am wondering if this may be necessary to do as well as install a water pressure regulator if it is necessary.

Are there any detrimental effects to the machine, pump, espresso etc. of water pressure that is too high or too low?

[cannonfodder]

Without a consistent input pressure, you will not get a consistent output pressure. I had problems with too much line pressure. My machine was set at 9 bar drawing from a static tank. When I hooked it up to a supply line at 70psi, my brew pressure shot off the gauge (12+ bar). I installed a heavy regulator to step my pressure down. I ended up at 25psi on the regulator. I readjusted the pump to 9.5 bar with a blind basket and I get 9bar at brew.

Others are better versed in the virtues of water, but if you have a water system that experiences pressure swings, you may want to put an accumulator tank. As long as you are taking the time to put in all the parts, you might as well toss in a carbon filter and softener if you have overly hard water.

[kaioslider]

Hi dk,

Someone over at coffeegeek's forums is having a problem with the Vetrano leaking, and he's on his second machine. I suspect it's the line pressure, as far as I can tell, he has no regulator and is on town water. Is static water pressure is 4 bars, mine is just under 2 bars, so I thought this was confirmation of what I suspected, but another Vetrano poster says he as his static at 4 bars too with no issues, but has a regulator. My other guess is that there is a bouncing in the water pressure, non steady pressure, which may account for the difference between the two. I got a regulator valve, my biggest concern was that as other building occupants use water, my water pressure bounces. I figure my regulator is set at about 25 psi. For $25 I'd say add it to prevent any damage to a $1400 machine. The cg post is in the Espresso Grinders and Machines, but up to this point it hasn't been very productive.

Dan

[HB]

For $25 I'd say add it to prevent any damage to a $1400 machine.

My concern about very high static pressure is that the boiler refill solenoid would fail to close during an auto-refill, potentially in the middle of the night. The Elektra A3 labeling was most explicit about its requirements:


They are clearly stated in the Owner's Manual too

Max pressure of 4 bar (static) and maximum of 1.5 bar when the pump is running. Those seem like reasonable recommendations for the Vetrano too. The evaluation model I have is hooked to a pressure regulator set to ~2 bar. If your water pressure is very low or varies widely (e.g., due to being on well water), an accumulator would help. I got one for the FloJet and it worked wonderfully at EspressoFest supplying two rotary pump espresso machines.

[kaioslider]

I should also have mentioned that the poster I was referring to said this problem after he shut the machine off. It's one thing to have solenoids and switches, but if they need power..........

[HB]

A "normally closed" solenoid only needs power to open, otherwise a spring holds it closed. I have read reports of some machines' grouphead solenoids dripping above 60 PSI, though the Cimbali Junior never complained about it (I had only one pressure regulator at the time and Junior lost). Either way, it seems prudent (and not costly) to install a pressure regulator.

[dk]

Thanks for the input I will be installing a pressure regulator just to be on the safe side.

[edwa]

I had problems with too much line pressure. My machine was set at 9 bar drawing from a static tank. When I hooked it up to a supply line at 70psi, my brew pressure shot off the gauge (12+ bar). I installed a heavy regulator to step my pressure down. I ended up at 25psi on the regulator. I readjusted the pump to 9.5 bar with a blind basket and I get 9bar at brew.

Is the heavy regulator you installed different than the one Chriscoffee sells? If so can it be found easily from a plumbing supply firm?

If I understand you correctly, once you install the regulator you need to readjust/recalibrate the pressurestat to fit your water supply. Regardless, of how the machine was set-up by the technicians? Is it enough to use the blind basket or do you need a pf with gauge?

[edwa]

From How do you descale a non-reservoir machine, ie. Vetrano?

It's easy. I added a tee and two stopcocks. The tee leads to a jug of descaler. To descale, I turn off the mains water stopcock and open the second stopcock leading to the jug. When the pump calls for water, it will draw from the jug.

Soooo, in times of desperation - like when the missus is in another remodel project and the water is turned off I can still have my Java by using a jug of water in place of the jug of descaler?

I thought going direct connect would be very simple; just tap into a supply, filter, and regulate the pressure to max out at no more than 30-35 psi. But, unless I misunderstand other posts the incoming pressure becomes another factor to balance in the equilibrium of grind, distribution, tamp, dose, temp, brew pressure, bean freshness, and water quality?

If so, is this true for both vibe and rotary pumps or just rotary?

[erics]

The pressure measured at the inlet to the espresso machine affects the pressure developed by the pump. The pressure developed by the pump is brew pressure, typically anywhere from 8.0 bar to 9.0 bar with 9.0 bar being a "favorite". One bar is about 14.5 psi (14.5038 psi) and the inlet pressure will affect the outlet pressure on a one for one basis. This pressure and any variance it may have has no influence on the pressurestat setting or vice versa.

Normal water pressure in a home is, say, 60 psi. However this can vary between 45 and 75 psi depending upon what other fixtures are in use AND whether or not your neighbors decided to hold a car wash fund raiser. This is why a pressure regulator set to maintain, say, 35 psi (or whatever the espresso machine mfg recommends) is a necessity. It is also a good idea, as you say, to install a filtration system and you might also need a water softening system in areas of hard water. Call your local water authority gurus and compare their numbers to the numbers found in this document and you can easily make an informed decision.

http://www.big-rick.com/coffee/waterfaq.html

The majority of all water pressure regulators have a port for attaching a pressure gage which measures the controlled pressure and the acid test for ANY water pressure regulator is how well it performs when other fixtures are operated simultaneously. Start pulling a shot and ask someone to flush a toilet. You MIGHT see a small blip (1 or 2 psi) that quickly returns to setpoint but that will have no effect on your product.

Eric S.

[SLC]

I went through a few water pressure regulators attached to Andreja to no avail. My problem was that my water pressure regulator next to the main water shut off valve for the home was not functioning properly.

I replaced it and then the water pressure regulator attached to Andreja worked fine.

An $8 pressure gauge from Home Depot helped me diagnose the problem. Just attach it to the water heater and see your home pressure and how much it is fluctuating. It should not fluctuate and should be around 40psi. If not then the regulator attached to your coffee machine cannot function properly.

Mark

[HB]

My problem was that my water pressure regulator next to the main water shut off valve for the home was not functioning properly.

Same thing happen to me and some of my neighbors. The house's static water pressure would creep up to mains pressure (110 PSI) due to the regulator's seal failing. I could have bought a rebuild kit, but decided after 15 years, it was worth replacing with a heavier-duty regulator. The symptom is a "whoosh" from the faucets after the water's been off for a few minutes followed by a normal flow rate.

Ironically I first noticed the problem while trying to regulate the pressure on a Cimbali Junior (rotary). The pressure would creep up just a half bar over 30 seconds of a deadhead pressure check, but not an extraction. The slow flow rate of an extraction was enough to hide the seal blow-by of the house's pressure regulator.


From Testing Brew Pressure

[cannonfodder]

Is the heavy regulator you installed different than the one Chriscoffee sells? If so can it be found easily from a plumbing supply firm?

If I understand you correctly, once you install the regulator you need to readjust/recalibrate the pressurestat to fit your water supply. Regardless, of how the machine was set-up by the technicians? Is it enough to use the blind basket or do you need a pf with gauge?

Sorry, did not see your post. I had the one Chris sells, plastic body and adjustments, it did not hold the pressure.

The one I got was from my local mega plumbing store (not a big box hardware store, a real plumbing supply shop) and is heavy brass construction. It is designed for pressures higher than my mains can put out. Add a pressure gauge and adjust it.

I know I have been asked the same question before. Let me search the forums for the old post. I had the manufacturer's web page, model number, photos etc...

[cannonfodder]

Found it...

Look at this thread, Pressure regulator output is 70psi regardless of setting

Photos, links, etc...

[edwa]

Thanks for the link to the other thread. It reaffirmed some research I've done in the meantime. Here's some of my discoveries:

The pressure regulator sold by Espressoparts is for 1/2" pipe and is for 30 psi.,

The pressure regulator that Chriscoffee sells has a maximum output of 25 psi (as told to me by phone),

A similar looking one made of plastic or brass available at Grainger Industrial Supply has a larger psi range BUT they shut off if the pressure drops to 40psi or below. I've ended up with something similar to the brass coned shape pictured on the other thread,

Jim at 1st line said that 25 psi was too low for the Briccoletta and the preferred range should be 30+ to 55 psi maximum.

My house pressure is 80 psi and the pathway to the Bric passes through an Everpure H-300 filter. The Everpure tech told me that it would reduce the flow but they measure it at a different rate than psi. So, I got a 1/4" compression fitting attached a 1/4" poly tubing and then a couple of adapters to a pressure gauge that fits a hose faucet. From which, I learned there was maybe 1 psi pressure drop (I'm hoping that this will turn up on a search of this site in case someone else with an Everpure is looking for more info).

I've been talking to my plumber who did my kitchen remodel (has also installed quite a few commercial espresso machines) and he has been urging that I put a check valve inline. He said if a fire truck ever hooks up to the hydrant 2 doors down that it'll pull line pressure and the check valve will prevent dirty water (espresso waste?) from flowing backwards into the line. It's hard for me to imagine but I trust the guy and have seen it recommended somewhere else.

Unless someone has a caution to this, I figure better safe than sorry.

[HB]

I've been talking to my plumber who did my kitchen remodel (has also installed quite a few commercial espresso machines) and he has been urging that I put a check valve inline. He said if a fire truck ever hooks up to the hydrant 2 doors down that it'll pull line pressure and the check valve will prevent dirty water (espresso waste?) from flowing backwards into the line.

Sounds like a smart plumber who knows the plumbing code. In contrast, an incompetent do-it-yourself plumber managed to introduce sewage into our fresh water system, which forced a city-wide boil water order due to e-coli contamination while they tracked it down. Our municipality requires backflow protection. A check valve or a NC solenoid would work.

[dorkboy]

Ok, I am quickly going to tell you whats going on, and you tell me what I should/shouldnt do.

New Vetrano, 6 stage water filter with 1/4" complete tubing. I have a pressure gauge hooked up and when NO water is running, its at 71psi. WITH water running it reads 22psi.

On the vetrano gauge, with the machine NOT running it reads 4.75 bar. I have adjusted the rotary pump to give me just under 9 bar with the pump running.



There it is, what you guys think?

Since I want this machine to last me "forever", what do you recommend?


Thanks,

Scott.

[cannonfodder]

71 psi is a bit high but that big drop from 71 to 22psi when the water is flowing. The ¼ inch tubing may be a little small. I ran ½ inch for my Faema. I run it at 3 bar mains pressure for preinfusion. When the pump engages I do get a line pressure drop but nothing as drastic as your drop.

You will lose pressure going through all of those filters, that combined with the ¼ tube may be strangling you water flow. Your pressure regulator may not be able to hold your mains pressure either. I had to replace my regulator when I went to the larger line, detailed in the link a couple of posts up.

Check your machines spec plate (where the voltage, amps, SN are located) and see if it lists a maximum line pressure.

[dorkboy]

there is just a SN # nothing else. I checked that.

My pressure before the filters is 74psi!!! I am shocked that there was such a little drop. I was expecting more.


Sorry there are 2 water psi drops. one when I turn on the filtered water pressure, which I mentioned. The one I forgot is when the tap is turned on, it drops to 52psi.

[edwa]

A couple of questions.

You don't mention it, but is there a pressure regulator on the line? If yes, it might be faulty. My first one was bad, it wouldn't allow more than 20 psi to pass through it. By the way, I was told to expect only 3-5 years of life out of my regulator. There is an inner spring that is compressed while you turn the outer screw to allow greater water flow and over time this weakens and then fails.

A stupid question, BUT, have you checked your filters for debris that might have collected during your plumbing addition. How old is/are the filter(s)?

Have you considered using a static tank on the line after the filters?

I have seen on my own system that the pressure drops on the pull of a shot somewhere around 10 psi. I'm also using 1/4" but copper up until the T- off for the line to be used for descaling solution. I'm not familiar with a 6 stage filter but have you contacted the manufacturer to find out what should be expected from the unit?

If you hire a plumber, make sure they have experience with espresso machines. It will help in troubleshooting. Ask a local cafe owner/manager.

What does Chris @ Chriscoffee say? He's got to be one of your best sources for info.

Lastly, you don't say how your Vetrano is performing at the "just under 9 bar". Choking? Straining labored noise?