I wonder if the nylon screw was set at the factory with a type of thread sealant that would then harden. When you adjusted it, you broke that seal and no longer held pressure correctly?
Adjusting the brass screw does not cause any problems of this sort--I have done this repeatedly as I've dialed in my preferences on pressure, and no ill effects. I have heard, from you and others, that the pressure gauge is wrong on the machine, but that it's consistent. i.e. if it reads 9 and is really 10, it will always read 9 and be 10. So this allows relative adjustment--I decide to back the pressure down then I can rely on the new reading being a certain level below the original reading, and can work towards the desired result, even if I don't know the actual pressure reading. Does that make sense? Someday I'd like to borrow a PF gauge and find out how good or bad mine is, but until then, I have to work in the relative world. tx, bmc "Faith will move mountains, but you'd better bring a shovel....." > From: Allen Worrall <[EMAIL PROTECTED]> > Reply-To: <[email protected]> > Date: Tue, 7 Oct 2008 08:33:26 -0800 > To: <[email protected]> > Subject: Re: Changing brew pressure > > > I recommend not messing with the screw behind the drip tray. Do some > research on the type of over pressure valve you have. If you have the "old" > one, and you mess with it, you may create problems. A few months ago I > posted some information about this, so hopefully you can find it. > > I replaced my "old" OPV with one I obtained from the UK, and I am very happy > with the result. The other thing that I have posted about in the past is the > fact that the pressure gauge on the front of my Brewtus II reads two bar > high. I went to considerable trouble, time and expense to determine this. I > found that the portafilter pressure gauge that was sent to me by WLL shortly > after I bought my machine was accurate, the gauge on the machine was not > accurate. > > My machine had tape over the hole behind the drip tray, with a posted note > saying not to mess with this. I ignored that after about 2 years, and found > that the OPV adjustment screw (white nylon) had a cotter pin in front of it, > further to discourage adjustment. I removed the cotter pin and made my > adjustments, and then started having all sorts of pressure problems. I > understand later versions of the Brewtus II had a different OPV with a brass > adjustment screw. However, before I obtained the excellent valve from the > UK, I sent to WLL for a new OPV and they sent me the "old" one with the > white nylon screw. > > Allen > Fairbanks, AK USA > > -------------------------------------------------- > From: "EspressoJB" <[EMAIL PROTECTED]> > Sent: Tuesday, October 07, 2008 7:37 AM > To: "Brewtus" <[email protected]> > Subject: Changing brew pressure > >> >> I search the archive and found lots about diagnosing brew pressure. I >> just need to know how to lower the brew pressure on my Brewtus II. It >> is brewing at 11 bar right now, and I would like to adjust it to 9 >> bar. If someone can just point me to a post, I'd appreciate it. >> >> I know that I am going to be turning the screw behind the drip tray, >> but do I do that while the pump is on? >> >> Thanks in advance. >> >> Demian >>> > > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Brewtus" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/brewtus?hl=en -~----------~----~----~----~------~----~------~--~---
