I am having a small problem with my La San Marco - Sprint-E, 2 group machine. The Auto Re-fill has stopped working. When the tank level gets low, I hear the pump come on, but nothing happens. Instead, I have to press the manual re-fill lever until the green water level light stops flashing.

I have checked all the obvious valves etc. but can't seem to find the location of the problem - probably a solenoid operated valve.

Any ideas or pointers are most welcomed

Hi

There is a probe in the boiler that is connected to your circuit board; it is insulated in a teflon sleeve from anything connecting to ground(earth). When the water in your boiler rises and touches it, the board knows that there is sufficient water in the boiler, when the water level drops below that probe and the probe is not grounded a relay/'s close a circuit/'s to your pump and inlet solenoid valve thereby pumping more water in your boiler until the probe is grounded again.

Your pump is turning on so it means that the sensor part is working, you just need to determine if your solenoid is getting power when the pump turns on, if it does it means that it is either a faulty coil, scaled up internals or the pipe going to the boiler from your solenoid is blocked.

Ok. I took the solenoid apart (don't know why I had trouble finding it before?), cleaned it - no scale but kind of a brown coffee looking stain inside the stem - and replaced it. Still no go. There is power to to the solenoid.

So it's time to replace the solenoid. The solenoid is a Sirai L121D04 za34a for 220/50hz-240/60hz. I found several in the UK and Europe but none in the US. Does someone here know of a US source or an acceptable substitute? I believe the ZA34A is a special heat tolerant version of the Sirai L120

So it's time to replace the solenoid.

Not necessarily.

Why not follow the excellent advice given above?

. . . if it does it means that it is either a faulty coil, scaled up internals or the pipe going to the boiler from your solenoid is blocked.

Are you sure it is the boiler fill solenoid you "took apart" ? Post some pics of the machine's internals. In any event, I would say go here for some parts - http://www.espressoparts.com/ - but it sounds to me that the line from the fill solenoid to the boiler may, in fact, be clogged with scale.

Well, I am fairly certain it was the refill solenoid, it is plumbed in parallel with the manual refill valve. The machine is closed up right now or I would post a photo. l also am pretty sure water is getting to the solenoid, cold water was available at the valve core when I had the operating mechanism removed. The internals of the valve and connecting brass fittings were all clear as well. In any case, scale is unlikely since the machine is fairly new and has always been plumbed to softened, filtered water.

Some of the parts on the espresso parts.com web site look close. I'll give them a all next week.

Thanks

I forgot I had this photo I took to ID the solenoid. It does not provide much context, But, if someone knows the machine it should be fairly obvious if this is the right solenoid.

Note: a) the picture was taken from the right hand side (as you face the machine) b) the white material is insulation.

Looks right to me . . . what threw me off was your comment about " trouble finding it" and the "brown coffee stain".

Shut the water off to the machine, disconnect the pump electrically, and gently remove the terminal connection at the water level probe. This action would normally start the pump and open the fill solenoid. With the pump electrically disconnected, all should be pretty quiet around the machine and you should hear a "click" when you break that probe connection. I know you said you had voltage at the coil but a faulty coil would result in no "click".

Thanks for the suggestion on testing. At this point I have eliminated the electrical supply, cold-water and tank refill lines.

So, it is either the coil (most likely) or the valve guide (less likely, since the plunger seems to be clean and move freely). But, in either case I probably wouldn't hear the click of the valve stem being drawn upward. So, since this is not an "ack, NO COFFEE" situation, I will probably just replace the coil (if it is possible to find a coil matched to my valve guide) and see what happens. That is pretty easy to do and then I will know more.

For those interested in the outcome... It was the coil. I ordered a replacement solenoid set from Michaelo Espresso and they happened to have an old Sirai on hand. I just swapped the coils and the machine once again refills without my help.

BTW, for LSM owners, Michaelo Espresso is a great resource.