I've been a lurker here at HB for quite a while, but haven't managed to ever find a question that wasn't already answered! So, an initial belated thanks for all the great info here, including the initial reviews, and tons of posts after.

I've been a very happy owner of a Bezzera Strega for about one and a half years. On Monday, just as I was pulling a shot right after lunch, I had my first trouble with the Strega.

I was doing my "normal" pre-heat-in-a-hurry where I let it heat up some, and then pull hot water through the group via the lever-then-vibe pump, which worked fine.

Then, I went to pull the shot, and the vibe pump didn't start when the lever hit the microswitch. Also, I realized that the heating element was no longer engaging.

Now, if I let it cool down and turn it back on, it's the same deal: no heat, no vibe pump.

I've opened it up and looked at a couple of things:

- The heating element in the boiler looks fine: measures 10.2 ohms on a multimeter.
- What I think is the pressure-stat seems to be OK: if I buzz the two sides of it when it is cold, the circuit is completed. Just to be sure I'm looking at the right part: it's the cylinder-ish thingie right below the main on-off switch with the screw to adjust the p-stat setting on top.
- The microswitch in the lever to engage the vibe pump seems to be working - I can measure it open normally with the multimeter, and then closed if I pull the lever all the way down.

So, now I'm a bit perplexed, and trying to figure out one thing that could cause BOTH the heat not to go on, and the pump not to engage. I've started to try to match up the electrical diagram to the parts in the machine, but it's slow going so far.

Anyway, any ideas on what I should look at next?

Thanks!

Morgan

How about the empty tank circuit? That will knock out the entire machine. It's the two screws in the tank and the connectors to those. Make sure they seat right, or try jumping a wire between them and see if the machine turns on. If you are using distilled water (shame on you if you are), this circuit will be prone to malfunction. But it is fiddly, and just slapping the tank a few times will sometimes turn it on or off.

another_jim wrote:How about the empty tank circuit?

+1
You should notice when the machine is on there are 2 lights lit on the front. If the bottom one isn't lit up it's probably a good idea to check the empty tank circuit first. There's also a jumper position inside the machine, that you can use to bypass the sensor as a test - if I remember correctly.

Great idea! Unfortunately, I just jumpered past the empty tank sensor, and I see the same thing. Details: I disconnected the two connectors that go to the two screws on top of the boiler, and shorted them together (on the dangling connectors).

When I turn the machine on, I get the same thing. On the lights: the on light comes on and stays on, but the heating light below it flashes briefly and then stays off.

Drat, I really thought that sounded so promising! Any other thoughts? I wonder about the vibe pump, and then also the box labeled RL3 in the wiring diagram - it seems to have lots of connections and if it went bad, maybe it could cause this trouble?

Oh, forgot to say: definitely not using distilled water.

If I go completely silent, I apologize in advance: I'm going to be gone for two weeks.

Morgan

mojo3344 wrote:When I turn the machine on, I get the same thing. On the lights: the on light comes on and stays on, but the heating light below it flashes briefly and then stays off.Morgan

Which is exactly what the tank Strega will do if you run low on water or turn it on with the reservoir out. It would certainly seem like something in that circuit is tripping the "no water" safety feature.

Great idea! Unfortunately, I just jumpered past the empty tank sensor, and I see the same thing.

The low water level in the reservoir is a capacitive sense circuit. There is one wire (I colored it red in the pic below) which is attached to a male spade terminal on one side of the reservoir. It connects to the RL3 control box as I have shown. To bypass this safety feature, detach it from the reservoir and ground it.



This artificially tells the RL3 that all is well. If your machine does not power up after doing this, then either the relay in the control box is faulty or the transformer (also in the control box) is faulty.

erics wrote:The low water level in the reservoir is a capacitive sense circuit. There is one wire (I colored it red in the pic below) which is attached to a male spade terminal on one side of the reservoir. It connects to the RL3 control box as I have shown. To bypass this safety feature, detach it from the reservoir and ground it.

Hmmm, I'm missing something - I'm not figuring out which is the male spade terminal.

I see three spots where there are electrical connections into the boiler - the heating element on one side, and then this on the top:



And then, this taken from the side with the connections on the bottom of the boiler:



What I did initially was on the top one, thinking it was the level sense - disconnect, then jumper. I'm not seeing a single male spade connector going into the boiler, what should I be looking for?

Morgan

Whoops, you said side of the reservoir, not the side of the boiler. Must learn to read more carefully, especially when asking for help....

Morgan

Ha! Looks like that did it! After grounding that reservoir sensor wire, I power it up, and I get both heat and vibe pump.

When I powered it up, it took a loooong drink of water from the reservoir, maybe 25+ seconds. Possibly because it thought the reservoir was empty/not there for a some time? I hope the heating element in the boiler isn't affected.....

So, a bad capacitive sensor on the reservoir then? What's the fix? Replace the sensor?

Thank you!

Morgan

Did you check the other reservoir wire that supplies the ground? Might be loose or bad a connection.