This Premier S 2 group machine worked fine for 6 years after I took it apart and rebuilt it. Yesterday, it started pouring too much water out of the 2 steam wands and blowing water out of the safety release valve. The water gauge glass pipe is almost 3/4 full; it use to hover around 1/2 full. From doing some online research I suspect it is the Sirai valve. Any other possibilities?

To me, it sounds like boiler overfilling. Have you checked the connection to the water sensor at both ends? Also, the grounding of the boiler.

Also check both fill valves. Solenoid and manual fill valves can begin to leak with age. Manual fill valves are generally serviceable where as solenoid valves are often not.

Thank you both Ministry and Nunas for your suggestions.

I am not an expert and basically broke down and rebuilt the two group Nuova Simonelli with the help of my iPhone documenting where every piece of machinery came from and had to return to after cleaning. Fortunately, the only repair I had at that time was a water pump rebuild that I sent out to repair. Consequently, I don't really know what and where the fill valves are. I think the 2 Parker valves by the group heads are probably OK. I don't have water leaking through the group heads.

Both steam valves were leaking for a few days before the major breakdown occurred. I took them off the boiler to see if any valves were involved with them. It seemed to be all clear pipes to the boiler. So the problem has to do with the boiler getting either too full or too hot.

There is a wired needle that relates to the fill level of the boiler. I pushed that in a bit and then pulled it out a bit and don't know if I screwed up the best setting for it. Nunas, is that one of the water sensors you mentioned? Where might the other sensor be?

I can look down on what I think is the Sirai valve and that looks fairly old and crappy. I think that is the solenoid fill valve that MinistryofEspresso was talking about. I don't know where a manual fill valve might be.

I've got to find my pictures and paperwork from 6 years ago before I can get started taking the machine apart.

Thanks again for your help.

There is a wired needle that relates to the fill level of the boiler. I pushed that in a bit and then pulled it out a bit and don't know if I screwed up the best setting for it. Nunas, is that one of the water sensors you mentioned? Where might the other sensor be?

Yes, that's it. On most machines they are fitted into a pressure-tight sleeve; this allows setting the height of the water in the boiler. The single wire should go to your 'controller' (usually a black box with a bunch of pin connections. The circuit must be completed through the ground (frame). So, there must be a ground wire on the controller and the boiler must be grounded. The setting is not particularly critical. If it is too high you'll get wet steam. For there to be actual water pouring out the steam wand, then this circuit would have to be not working. That could be the sensor probe, the wire from there to the controller or the fill valve (solenoid). Since you've moved the sensor and are getting water, I think I'd be inclined to push the sensor farther into the boiler and see what happens (probably no change...but you never know ).

To test the fill circuit, remove the wire from the sensor. You should be able to make the solenoid valve click on and off by grounding and ungrounding the end of the wire. With the wire grounded, the controller should think the boiler is full and it should shut off the solenoid (and probably the pump too). With the wire not grounded and not connected to the sensor, the controller should call for water endlessly (pump on and solenoid open).

Nunas,
Thanks for getting back to me.

I tested the sensor with a ground wire to the fill sensor wire (disconnected from the needle) The solenoid turns on when I connect the wire to ground and the water stops running through my steam wands.

When the wire is off the pin and not grounded the steam wands are pouring water.

When the needle is connected to the wire all is OK until the boiler gets to a brewing temperature and then the steam wands pour water and soon the safety valve pours water.

Any other tests that you can suggest?

Thanks

I'm thinking that it is my auto fill control (pictured with the pins at bottom) that is causing hot water to pour out of my steam wands.
The auto fill is attached by the 8 pin receptor in my machine (on left). If it is not that $180 device, it may have something to do with the box to the right of the blue pin mount. I don't know what that box does but it looks water related.
The boiler is to the right of the box.

I'm hoping that someone can point me in the right direction.

Finally figured it out. Nunas and Ministry of Espresso got me in the ballpark of what caused water to pour out of my steam wands. My hesitancy was in buying an $180 non-returnable water level regulator for a machine that I had bought and rebuilt for less than $400. (That included buying the tools to do it.) I finally bought a Gicar solenoid for $90. It was a pug'n'play fix. All I had to do was siphon a couple of glasses of water out of my boiler to open up some space for the new water regulator to operate correctly.

In the mean time, I pumped coffee thru my trusty Pavoni lever and my old Gaggia Baby for my daily shots. I was impressed at how good they both tasted. You don't need the best espresso machine to make damn good espresso. Roasting and grinding my beans with decent gear are certainly important for success with the final pour.

Thanks for the help.