# Gaggia Classic change in noise and steaming through group head



## rwcwilson (Sep 2, 2015)

Hi,

I bought a gaggia classic from this forum a few weeks ago and it was working fine until a week ago when half way through an extraction the machine made a loud noise and the pump became a lot quieter. The pump remained quiet the next time I used it but it was still working and I could extract coffee through the group and the steam wand was working fine. So i decided to descale the machine and following this the pump was a little bit louder but it wasn't back to how it was.

Having scoured this forum there are a number of users who have had the same problem, so I followed the advice of responses on those threads. I changed the solenoid (as the seller provided me with a spare one) but this didn't help, so I back flushed it a couple of times and descaled it again. The second descale helped and the pump sounded even louder (but still not back to the original volume), so having found that I was still able to extract coffee and steam I thought that maybe the pump was just a bit loud in the first place; e.g. following it being shipped to my house, as I noticed it is quite free-moving in the metal casing and therefore just though it could have been hitting the side or something.

However, today I used it again and after leaving it for 15 minutes to warm up, I flushed the group head and when I did so steam and water came out, and it did the same when I flushed at the end; the coffee didn't taste all that great either (but these are different beans so they may just not be nice







). So I'm a bit stuck really and disappointed that this machine has been a bit of a pain in the backside. Next steps? Is it going to need a strip down?? The seller did say that he had descaled the machine and the boiler so I'm a bit astounded that it has already having problems.

Cheers,

Rich


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## Jumbo Ratty (Jan 12, 2015)

When you back flushed it was it with just water or did you use the appropriate cleaning agent like Urnex Cafiza?


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## rwcwilson (Sep 2, 2015)

Thanks for your reply, I used Urnex Cafiza


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## Jumbo Ratty (Jan 12, 2015)

Oh well, its not that then, as a blocked solenoid would sound quiet compared to usual. But seeing as how youve done that I cant see that being the problem.

Have you removed the shower screen since descaling and backflushing?

Could be some detritus between the dispersion plate and the shower screen. its just a small philips screw holding it in.


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## rwcwilson (Sep 2, 2015)

Sorry I forgot to mention I took the shower screen and dispersion plate off, cleaned them and soaked them in trisodium phosphate (as recommended on a maintenance website). Put it back together and didn't make much difference. I did this before the second descale.

I should also note that the OPV tube that goes back into the reservoir vibrates pretty mad when I've turned on the pump, even without the portafilter in it. It did have a OPV mod done before I bought it to 10bar, so don't know if this is normal.


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## Jumbo Ratty (Jan 12, 2015)

Im afraid I have exhausted the sum of my knowledge regarding what could be wrong.

I hope you find the solution and its a simple fix


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## rwcwilson (Sep 2, 2015)

Thanks for trying


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## timmyjj21 (May 10, 2015)

Interesting symptoms. What did changing the solenoid involve? Was it just the black cube, or the whole metal valve assembly?

Things that come to mind with a classic:

1) load noise=failure. Sometimes if the pump has air in it, it makes a nasty rattle, but it resolves quickly.

2) Vibrating return hose could be a primary pump issue or could be OPV related, but the pulse makes me think pump first.

Opening the OPV is annoying if you don't have a pressure gauge to set it back again, so I would start with the pump.

http://ulkapumprepair.blogspot.co.uk/2008/10/original-website-page.html?m=1


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## rwcwilson (Sep 2, 2015)

I changed the whole valve, i.e. the black box and the metal valve (so the whole valve assembly). The original one was the pre-phillips solenoid and I changed it to the new one (which was the spare one).

Yeh so there may just have been air in the system from the delivery, but it did run fine for quite a while in this state, so I would have thought the air would have cleared after a couple of weeks use.

Would this also correspond with steam coming out of the group head? because I guess if the pump is failing then not enough water will be getting into the boiler. Would it therefore not be better to just buy a new pump? They don't appear to be horrendously expensive for a Classic, ~£15


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## timmyjj21 (May 10, 2015)

Ulka pumps are pretty cheap. If you were getting a new one I would consider an Invensys instead. I'm not confident it is the pump, so my personal preference would be to take it apart first to check. The valves can get jammed with tiny bits of grit or sediment. If you are not that way inclined, then its only a small investment for a new one. @gaggiamanualservice.com may have more insight.


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## El carajillo (Mar 16, 2013)

Is the tube bringing water from the tank to the pump pinched or kinked ?


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## rwcwilson (Sep 2, 2015)

timmyjj21 said:


> Ulka pumps are pretty cheap. If you were getting a new one I would consider an Invensys instead. I'm not confident it is the pump, so my personal preference would be to take it apart first to check. The valves can get jammed with tiny bits of grit or sediment. If you are not that way inclined, then its only a small investment for a new one. @gaggiamanualservice may have more insight.


I think I might take it apart at the weekend and have a look at everything before buying the pump



El carajillo said:


> Is the tube bringing water from the tank to the pump pinched or kinked ?


I took the top off and had a look and there weren't any kinks in the tube (there wasn't a kink leading down into the resevoir either). I turned it on and left it for a little while and it didn't steam this time though, however it did seem a bit hotter than normal, as the water was steaming a bit more than usual. Tbh I did leave it longer when I had it on earlier (it might have been much longer than 15 minutes on reflection), so maybe I just left it too long and the temperature regulator is a bit off. So still not really sure what is going on :S


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## Sharkie (Apr 29, 2013)

If you have steam coming out of the group head and the coffee is tasting off it sounds like the contact thermostat part number DM1168

You can get them on eBay for less than ten pound posted.

Had the same problem on my brother in law's baby twin recently and this was the problem


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## timmyjj21 (May 10, 2015)

@rwcwilson how did you go with your issue?


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## rwcwilson (Sep 2, 2015)

Hi Timmy,

I'm not sure whether its resolved or not. I just left it because by the weekend the over-steaming issue seemed to resolve (so maybe there was a kink in the tube??) and it is still making great coffee, so its difficult to say whether it's gone from abnormal to normal (i.e. the original sound was abnormal) or whether it is still a bit clogged. I'd need to compare it with a working machine to be able to tell but obviously I don't have access to one! So as long as its working as it is I won't take it apart but if anything goes on the blink again I'll strip it down and clean everything.


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