Could it be so simple as a pressure stat set to low, or defective?

Mmmm Marble

Mmmmmmmmm Granite! Will be installed late this week, early next....

Waiting on parts from EPNW. Will assemble towards end of week and hopefully all will be well.

"Cannonfodder". My problem may be anything at this point, or nothing once I get all the bits assembled correctly, but if it gets to the point that I need to set or check the pressurestat, how do I do it?

Regards John

SUCCESS!

After completing the rebuild of the steam and hot water valves, installing identical parts in each; and after installing a new O-ring in the vacuum "thingy" on top of the sight glass; and after installing a new double pressure gauge......I am drinking espresso!

One item of note and that is it took about 20-30 minutes for everything to heat up so that I got a reading on the top gauge.

Everything seems to work (picture of pressure gauge attached). I fiddled with the pressurestat, by turning the adjusting screw this way and that about a full turn till I got it settled down so that it now cycles the heating element on/off before pressure moves into the red zone. In the process tested the pressure relief valve (Whew, it works!). Also the boiler seems to autofill correctly after I deplete it by drawing off hot water.

Steamed some milk in record time. This machine has a reputation for fast work and it really cooks.

I must say that the hot water valve delivers about as much steam as water however! Really blasts away. Is this to be expected?


Thanks to all who advised and assisted. I've included a good photo of the manual lever at the request of "jesawdy". You were very helpful.

Regards
John

Great news! I think that's a pretty slick looking machine.

What do you think the problem was or do you think it was a series of issues?

Did you end replacing the gauge? What do you have the boiler pressure set to?

chezJohn wrote:I must say that the hot water valve delivers about as much steam as water however! Really blasts away. Is this to be expected?

That's typical for a machine that uses a downtube into the superheated boiler water.... The steam pressure is pushing the water out and it will flash boil as it comes out. Anything more than a few ounces and it will be lots of steam. If you are at a particularly high boiler pressure, it may be even more so. It is great for heating cups, etc... but I would be hesitant to use it for Cafe Americanos, etc., unless you pull the water first, and then pull your shot on top of the water (my preferred method anyhow). This gives the water a chance to cool a bit and warm the cup, otherwise, you get a crazy hot drink.

How's the espresso?

jesawdy wrote:What do you think the problem was or do you think it was a series of issues?

I think there were several problems/issues:
1. The vacuum advance was leaking thus not allowing the boiler to pressurize correctly.

2. I don't think I allowed sufficient time for the machine to completely heat up in my first test. As evidence, today, when I allowed unlimited time, I observed, using MY NEW PRESSURE GAUGE, that it took about 20-30 minutes for the boiler pressure to register above 0 BAR. When pressure finally rose to approx 1.0-1.5 BAR I was able to draw steam and hot water! There may never have been a problem with valve components or assembly because I just didn't wait long enough!

3. The Sirai pressurestat may have been stuck as was earlier suggested. I have been making repeated adjustments to it to allow maintenance of boiler pressure between 1.0 - 1.5 BAR (as observed on the pressure gauge, which has pretty gross indicators).

The espresso is pretty good, but I have a lot to learn and experiment with regarding tamp/pressure/grind with this machine.
My first 3-5 pulls were flowing a bit too quickly.... about 15 seconds for double shot. Modest crema, a bit blonde, underextracted...

As an experiment, I have to switch the location of a "group head water pressure reducer". Presently it is in the right inlet port on the GH, (viewed from the rear) but it may go into the left port. I spoke with the guys at EPNW and I think I may have misunderstood their instructions.......It COULD alter the timing/flow by altering the flow into the GH. I'll switch it tomorrow and see what happens. (it's just a small little disk with a hole in the center that slip/fits into the inlet)

NEW CONCERN:
After my initial excitement and self-congratulation, aided by understanding praise from loving spouse, I left the machine idling while having dinner. Much to my surprise (really?) the boiler pressure rose into the red zone (above 1.5 BAR) and the safety steam valve did it's job. I turned off the power and allowed the boiler to cool, then I applied the screwdriver to the adjustment screw on top of the Sirai (old gray model) to lessen the pressure (turned in the "-" direction) and observed that the heat cycled on and off regularly about every 1-2.5 minutes. Left the machine alone to do some reading and the steam pressure valve popped off again about 30 minutes later! Anyway, I went through about 4 iterations of this process, tweaking the adjustment screw each time, and have concluded that the membrane in the pressurestat must be shot.

Would you concur?

... split from Used La Pavoni Pub/S by Moderator....

jesawdy wrote:Are you considering repairing or replacing that pressurestat (I hope)?

Yes,

The pressurestat has to get fixed. I think its time to quit thumping on it when it fails to work and repair it. I'm always hopeful that it will magically regain its integrity. Remember the definition of insanity? "doing the same thing over and over and expecting a different result." That's been me. I think its time. Thanks for the encouragement.

chezjohn

For the record. Re: Grouphead design: This is the closest diagram to my machine's grouphead. It is 99% accurate to what I have: (also actual photo of mine)






chezjohn

Oooh... that's too slick. Item 11 is a magnet that is manually moved via the lever to operate the 3-way solenoid valve. Neato. Microswitch mounted above lever arm to activate pump.

hello john,

great to read that you have got everything sorted. most excellent work, patience and persistence! wanted to let you know that enthusiast ed needham has the same machine and has a page on it at his web site here: http://www.homeroaster.com/setup2.html

he makes a "mod" here: http://www.homeroaster.com/supermod.html

his site's home page is here: http://www.homeroaster.com/intro1.html

look forward to an update on how she is doing after getting p-stat squared away.

best wishes, hope you are enjoying some excellent extractions.

ideor