Announcement

Collapse
No announcement yet.

Bezzera BZ-40 pump pressure?

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Bezzera BZ-40 pump pressure?

    Hello coffee gurus! I just bought i bz40(1997) and the pump meter go's up to 7 or 8 bar when i open the water and when i brew it go's up to 9-10 bar what maybe the problem!???? I know there's a couple bz40 gurus please helllppppp!

  • #2
    Whats the problem?

    Comment


    • #3
      Originally posted by Jimmytheboot View Post
      Whats the problem?
      Hello jimmy!
      The bz 40 have a steam gauge and pump gauge! From what i see in videos on youtube the pump pressure is around 1,2 bar beFore brewing, when you start brewing its go up to 9bar! Mine is always at 7 to 8bar. It go to 9,10bar when brewing

      Comment


      • #4
        Is there a check valve or filter between the mains and the machine?

        The brew gauge reads the pressure at the pump outlet which would be mains pressure when not pumping

        Comment


        • #5
          Hello Evascroll,

          I know nothing about the BZ 40 and I haven’t used a plumbed in machine. However it is normal for pumps to be capable of pumping to 15 bars. As it is desirable for coffee to be brewed with the pressure somewhere between about 8-12 bar it is normal to have an over pressure valve to keep it down.

          If yours is brewing at 9-10 bars it is perfect. How is the coffee you make?

          Barry

          Comment


          • #6
            Originally posted by Barry_Duncan View Post
            However it is normal for pumps to be capable of pumping to 15 bars. As it is desirable for coffee to be brewed with the pressure somewhere between about 8-12 bar it is normal to have an over pressure valve to keep it down.
            Pumps usually have a pressure-flow relationship so that the higher the pressure, the lower the flow. The 15 bars is usually the pressure at zero flow, and there will be a flow rate at zero pressure.

            Rotary pumps add pressure onto the incoming water - and if your mains pressure is reading 7 bars it's probably a bit high and you might want to get a plumber to have a look at it (since the standard maximum for domestic mains pressure is 5 bars).

            What you see in the videos is probably running from a tank reservoir or an area with quite low mains pressure (although 1-2 bars is very low - that resembles tank water).

            (see http://www.pic.vic.gov.au/resources/...low_rates2.pdf)

            Comment


            • #7
              Originally posted by Jimmytheboot View Post
              Is there a check valve or filter between the mains and the machine?

              The brew gauge reads the pressure at the pump outlet which would be mains pressure when not pumping
              Hello jimmy! It have a filter before the machine! This are the test that i'm done! I check the water pressure in the house and wallaaa! 7 to 8 bar, sow that explaine why the machine have 7 to 8 bar at the pump gauge! (bad pump?) but wait when i start brewing it goes to 9 bar! Sow i did another test, i disconect the hose from the water and i put it in a bucket of water (the pump is desing to pump up to 250 psi) attached a pressure test on the other end off the pump and the magic number 1 came up! Sow my comclusion (8 bar from the water pressure of the house plus 1 bar from the pump= 9 bar at the pump pressure in the machine) faulty pump! I am not a mecanic but for logic i believe im rigth! If any 1 can give more light in the topic are welcome thanks

              Comment


              • #8
                Hello hildy! Thanks for the inf! About the water pressure regulation i wish is like that were i live(puerto rico) but that not the case in my hose i have to much water pressure and were my mother live (15 minute from me) it have almost no pressure at all! About the video that im seen i belive is the same machine (bezzera bz-40 but automatic) but i'm not sure! About the water tanks. (is the video that kosmo koffe post) i have to ask him in any case i order a new procon pump just in case! Thanks if you find something more i'm glad to hear

                Comment


                • #9
                  Originally posted by Evascroll View Post
                  Hello jimmy! It have a filter before the machine! This are the test that i'm done! I check the water pressure in the house and wallaaa! 7 to 8 bar, sow that explaine why the machine have 7 to 8 bar at the pump gauge! (bad pump?) but wait when i start brewing it goes to 9 bar! Sow i did another test, i disconect the hose from the water and i put it in a bucket of water (the pump is desing to pump up to 250 psi) attached a pressure test on the other end off the pump and the magic number 1 came up! Sow my comclusion (8 bar from the water pressure of the house plus 1 bar from the pump= 9 bar at the pump pressure in the machine) faulty pump! I am not a mecanic but for logic i believe im rigth! If any 1 can give more light in the topic are welcome thanks
                  Its not certain anything is wrong with the pump, the gauge is reading your house water pressure which is really high.

                  When its pumping from the bucket it reads 1 bar or is that the reading with the pump off?

                  Comment


                  • #10
                    evascroll, you need to buy a regulator and place it in the plumbing line to your coffee machine; that will bring it down to the recommended 3-5 bars of mains pressure.

                    Comment


                    • #11
                      It doesn't sound like there is anything wrong with your pump.

                      The output pressure on a rotary pump will be different when pulling from a tank or from mains and will need to be adjusted to account for the input pressure. As far as the pump goes the only reading you need to concern yourself with is what the pressure is when the pump is turned on, and that should be 9 bars.

                      With 7-8 bars of line pressure I would strongly suggest installing a pressure reduction valve between the espresso machine and the water mains. Adjust the reduction valve until the pressure going into the espresso machine is 3.5 bars. Then adjust the pump so that it puts out 9 bars when turned on. Then enjoy your coffee!


                      Java "It's all relative!" phile
                      Toys! I must have new toys!!!

                      Comment


                      • #12
                        Originally posted by Evascroll View Post
                        Hello jimmy! It have a filter before the machine! This are the test that i'm done! I check the water pressure in the house and wallaaa! 7 to 8 bar, sow that explaine why the machine have 7 to 8 bar at the pump gauge! (bad pump?) but wait when i start brewing it goes to 9 bar! Sow i did another test, i disconect the hose from the water and i put it in a bucket of water (the pump is desing to pump up to 250 psi) attached a pressure test on the other end off the pump and the magic number 1 came up! Sow my comclusion (8 bar from the water pressure of the house plus 1 bar from the pump= 9 bar at the pump pressure in the machine) faulty pump! I am not a mecanic but for logic i believe im rigth! If any 1 can give more light in the topic are welcome thanks
                        That's not how it works. The pump is probably fine; it will be adding some pressure to it, and then the OPV will be releasing all pressure above 9 bars.

                        Comment


                        • #13
                          Originally posted by Hildy View Post
                          That's not how it works. The pump is probably fine; it will be adding some pressure to it, and then the OPV will be releasing all pressure above 9 bars.
                          Given that the bz40 is a commercial machine with a rotary pump I would be very surprised if it has an OPV.


                          Java "Pressure me up Scotty!" phile
                          Toys! I must have new toys!!!

                          Comment


                          • #14
                            Many of the rotary pump machines we sell also incorporate an OPV. They are usually set to 12 Bar and act as a fail safe should the pump bypass fail for any reason.

                            Comment


                            • #15
                              Originally posted by Talk_Coffee View Post
                              Many of the rotary pump machines we sell also incorporate an OPV. They are usually set to 12 Bar and act as a fail safe should the pump bypass fail for any reason.
                              On plumbed in commercial machines? Interesting, hadn't seen that before.


                              Java "Always learning" phile
                              Toys! I must have new toys!!!

                              Comment

                              Working...
                              X