Strange things, strange strange things in an Aurora. your opinions pls

[Paul]

Hi all,

I am rebuilding a 1985 Aurora (Brugnetti) 1gr HX machine. Got most of the way thru the teardown tonight and I came across two things I am puzzled about. I would love your opinions on the following:

1. pstat
The machine has a new sirai. This is mounted under the boiler and its input is below the waterline. I have never seen this before. Does it do the membrane any harm?

2. autofill solenoid
The AF solenoid water feed is off a tee after the pump. I can't see how the autofill can work like this because there is no circuit to trigger the pump when the solenoid is open. I plan to re-route the plumbing so that the solenoid feed comes from a tee before the pump.

I bought this machine cheaply on the basis of a burnt out level controller. It is my first foray into pump machine overhall (though I have done a few commercial levers). I would love to hear any thoughts on the above.

cheers
Paul

[cannonfodder]

To my knowledge, the Pstat is normally above the water line. The level sensor may have been replaced and cut too short or moved up to high in the boiler. It is just a stainless steel rod with a wire on the top. You can lower it in the housing or replace it in the event someone cut it to short. On my Faema and Isomac, the Pstat line is on top of the boiler, however on my Faema (lever machine) it is on the bottom of the boiler and hence submerged.

The autofill solenoid relies on line pressure to fill the boiler. If you are feeding it off of bottled water, you would have to engage the pump to force water into the boiler, otherwise when the solenoid opens, the boiler pressure will push water OUT of the boiler like a hot water tap, which is very bad.

When I rebuilt the Faema, the autofill solenoid was missing. I capped the boiler fitting, ran a new line from where the solenoid use to hook up and mounted a brew pressure gauge off of that line. I hooked up a 240V yellow light to the solenoid line on the level box so if I don't notice the water level in the sight glass going low for some reason when the water drops below the sensor and the level box trips the solenoid line the panel mounted light illuminates. Like a 'check engine' idiot light on a dashboard. That also eliminates the autofill kicking on during a shot, right before a shot or during steaming.

You can run the machine without the level box, you just have to manually fill the boiler, which is what I do even with a working level box. Unless this is an automatic machine, then you do have to replace the brain box.

See my Faema Rebuild Project thread for more information. I documented the entire rebuild with photos.

[another_jim]

The Pstats on home lever machines all sense from the bottom of the boiler and are none the worse for wear. In general, if one looks at pipe fitting ratings, the ones for liquid are higher than the ones for steam, so if the membrane holds for steam, it's probably good for liquid too. However, these units may be slightly different models than the ones that sit in the steam.

[naked_barista]

Paul,
Welcome to the Brugnetti world! I've had my MC-1 for 15 years, and it's still going strong. Get it fixed and you've got yourself a fine machine there.

Larry