Noisy solenoid

MediumRoastSteam

The Elizabeth has started to make a very loud noise when brewing coffee. I’m 99% sure it’s to do with the group solenoid, as it starts when brewing and stops when I stop the process. It’s not the auto fill solenoid or the other two as the noise doesn’t happen when drawing water or the steam boiler fills.

I tried backflushing yesterday, and today again. Sadly it’s not going away. Machine is still under warranty, but if it’s a simple maintenance procedure, I’d rather to it myself.

@DavecUK - any suggestions?

DavecUK

You most likely have a bit of dirt stuck in the solenoid seal…I had the same on one of my Minimas (the blue one) it was a tiny speck of swarf. I made a post about it on CFUK some time ago now. Open the vent solenoid and have a look, you will most likely see something under the seat that seals…It might be very small. It then starts to chatter because it doesn’t completely seal.

MediumRoastSteam

Thanks @DavecUK . On the Elizabeth, what’s he best way to gain access to the core of the solenoid?

Remove covers;

Remove water tank assembly;

And then… ?

ST30B

MediumRoastSteam Cheers for your reply. I was mainly interested in those who have both niche Zero and now the duo, but good that you’ve had the same mignon as myself.

Workflow of the eureka is now annoying me as a single doser but equally is the noise level. I’ve heard the Zero first hand and the sound is much more pleasant. (Open plan kitchen, so important) I know the duo is louder but still a better sound than other grinders IMO.

DavecUK

Remove top, sides and water tank carrier

A = Vent tube

B = solenoid coil (should move Nucleus, with spring and seal) up a tube

C= Might be bayonet fitting, or could be a nut you have to undo

Remove vent tube, then remove B, undo nut on left…slides off (remember which wires connected to what, or leave them on if you can). Then you will see if C is a nut, or part of a bayonet type tool less fitting. After removal of that tube, depending on the type of solenoid, you should be able to remove the nucleus. Check seat and sealing pad for debris and remove.

If it’s not a type with a nucleus, you may have to go for more disassembly. Take lots of photos to be able to ask for more guidance, if it’s not like I think. There are different ways this can be done.

MediumRoastSteam

DavecUK - many many thanks!

I’m more worried of the prospect of not being able to make a coffee more than anything else! 🤣🤣🤣🤣🤣

Looks like I’ll be busy this week!

MediumRoastSteam

And it’s fixed. The culprit… a tiny spec of impurity as per the image below.

And some photos so to help anyone in the future. At the end, I plugged the hose back and secured with a cable tie (I clipped it afterwards)

JahLaza

MediumRoastSteam and @DavecUK thanks for sharing this and the photos - probably down the line at some stage for me!

MediumRoastSteam

Quick update on this. Machine working absolutely perfectly. Had two coffees, one in the morning, and one in the afternoon. I even backlashed it a couple of times just to be 100% sure. No crazy noises, nothing. Just perfect. Amazing how such a small particle of impurity can cause such a problem.

DavecUK

MediumRoastSteam Amazing how such a small particle of impurity can cause such a problem.

It’s because these solenoids are more highly balanced than people realise. The spring has to be strong enough to open against some pressure if the machine chokes…. This means if that nucleus doesn’t come back all the way and allow it to fully seal, you get the 50Hzchatter, as it tries to close and then is forced open again.