Announcement

Collapse
No announcement yet.

La Pavoni Pub OPV and the Pullman Gauge

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

  • DiBort
    replied
    Re: La Pavoni Pub OPV and the Pullman Gauge

    Originally posted by 282F2529460 link=1254118690/0#0 date=1254118690
    but my problem now is that if the machine is on for a while, and I press the brew switch, it takes a long time before water comes out of the head. This is without the handle engaged, in case you were wondering. I notice at this stage that the water in the reservoir dips down quite a bit.

    This leads me to believe that the HX pressure at idle gets pretty high, and pushes all (or at least quite a bit) of water back out the OPV.

    I also fitted one of these: http://www.1st-line.net/cgi-bin/category.cgi?item=3530023&type=store - - An air release valve for the ULKA vibra pump, which to my knowledge comes with this machine, but was removed from my machine before I got it.

    On the top of your group head is a filter and a jet(restricter) have you check that this are not block, sometimes if the restricter is block will not allow the water to come.

    Another thing that you can try is by setting the OPV at 12 bars and see how it reacts. Put the second hose and measure the amount of water return so you can have a better idea if is that or not

    Good luck

    Renzo
    Di Bartoli Home Barista Centre

    Leave a comment:


  • nico
    replied
    Re: La Pavoni Pub OPV and the Pullman Gauge

    Thanks for the reply. I also doubt that there is an issue with the HX. I read up that the air release valve lets out air/water at low pressure, and shuts off at 7-8 bar. The only issue is that I am sure there is a non return valve between the HX and the air release valve. I will strip it tonight, and see.

    I suppose it could be an unrelated three way valve issue that just happened to show its head the day after I made some adjustments. Anyway, I will see if I can have a look tonight, and figure this out.

    Leave a comment:


  • gregpullman
    replied
    Re: La Pavoni Pub OPV and the Pullman Gauge

    Originally posted by 7E79737F100 link=1254118690/0#0 date=1254118690
    Now, I suppose the water could be escaping through either of these devices, and I should probably fire up the beast naked, and wait and see where the water exits.
    Thatd be the thing to do. Pull off the panels, put the drain hoses into something else and let it idle for a while so you can see whats going on. The HX system should hardly be under any pressure at all with the pump deactivated but should remain full of water so the thermosyphon can run. If its not holding water it has to be going somewhere. I doubt itd be a cracked HX and water seeping back into the boiler- itd be worse under higher pressure which is the opposite to what youre experiencing.

    Leave a comment:


  • nico
    started a topic La Pavoni Pub OPV and the Pullman Gauge

    La Pavoni Pub OPV and the Pullman Gauge

    Hi all.

    So I got Gregs pressure gauge, and initial tests showed 15 Bar at the group. When I stripped the covers off, I realised that the OPV screwhead was damaged/stripped, and I could not busge it. Off I went to Euro Espresso to get a new one. Now, the weird thing is, the guys there told me this was not the place top be adjusting the pressure.

    So, in goes the new OPV, testing at 15 Bar. I gradually adjusted it out until I got to 9 bar. Shots came out a bit better, but my problem now is that if the machine is on for a while, and I press the brew switch, it takes a long time before water comes out of the head. This is without the handle engaged, in case you were wondering. I notice at this stage that the water in the reservoir dips down quite a bit.

    This leads me to believe that the HX pressure at idle gets pretty high, and pushes all (or at least quite a bit) of water back out the OPV.

    I also fitted one of these: http://www.1st-line.net/cgi-bin/category.cgi?item=3530023&type=store - - An air release valve for the ULKA vibra pump, which to my knowledge comes with this machine, but was removed from my machine before I got it.

    Now, I suppose the water could be escaping through either of these devices, and I should probably fire up the beast naked, and wait and see where the water exits. If its the air release valve, I will turf it immediately, but if its the OPV, should I crank up the pressure till the water no longer escapes (too much/at all), or leave it at 9 bar??

    I am scared too much water escapes, and the sudden cool water hitting the HX all at once causes some kind of damage.

    Heeeelllp, I guess.
Working...
X