Jump to content

Recommended Posts

Hi all.


I put up a video here with a problem with my Gaggia Classic a few days ago, and the consensus seemed to be that the solenoid valve had gotten blocked with scale debris. The machine is 2011 but new to me, bought second-hand recently. I have been trying to get myself set up over the last month or so, getting a second-hand Baratza Vario from a forum member, tamper, scales, airtight container etc. Also got a brass shower screen holder and gasket as the originals did not look too good.


The issue occurred, I think, after I put the machine on its side, to fit the new parts. (Really frustrating as I thought I was finally good to go, have yet to pull a single shot of freshly ground coffee on the machine!) After some helpful advice here I read up what I could on descaling and the issue in general, ran some descaler through a couple of times and used the method of intermittently switching on and off the steam switch.


I think I’m really beginning to doubt myself now as I have a fundamental question which might be obvious but I can’t figure out: Is there even supposed to be any water flow through the group head, when the steam switch is on?


From memory, the guy who sold me the machine, when showing me the ropes, switched on both the steam and and ON switch, before pulling an espresso. However, most online tutorials seem to have the steam switch off for such purposes. (I don’t drink milk, so steam function only really neeeded for visitors).


I have uploaded a short video showing how the water flows now, both with the steam switch on and off (in the former case, not at all), and I would appreciate any pointers or advice:


I think I will have to open the machine up and try to disassemble the solenoid valve, but as I said, I am doubting myself now. I should add that there is no water coming out though the pressure release tube, so that must indicate a problem is still there, no?


Really appreciate any help, I have posted a new thread as my main question is the one above, cheers! :time-out:

Link to post
Share on other sites

A while since I had my GC but, from memory, you press the central “steam” button only when you want the boiler to heat up to steam temperature. For just pulling a shot, you leave steam off and flick the brew button to pump water through the puck.


The steam knob at the side releases water or steam through the wand according to the pressure / temp inside the boiler: ie if you have flicked the steam switch and left it to heat to steam temp (the “heating” light has turned off = up to temp) the opening the steam valve will allow steam through.


If you are at normal brewing temperature (ie you haven’t flicked the steam switch) then opening the steam valve will only allow water through.


I was following your last thread, but that video looks like the machine is behaving normally to me.

Link to post
Share on other sites

That looks normal to me. So now leave the steam switch alone when brewing the coffee.


you won’t get any water coming out the down pipe as you haven’t got a portafilter in place full of coffee creating pressure.

if you were to put the blind basket in and then let the machine run until you heard the pump change noise and start to sound dull then switch the coffee switch off (far right switch) I would imagine you would then get the expulsion of back pressure water out of the down pipe.


the water coming out the dispersion plate flow rate looked fine to me btw

Link to post
Share on other sites

Just to check you understand the fundamentals of how this machine heats:


1) turn on the power with the portafilter attached. When the heating light goes out you are up to temperature.

2) flick the brew button with the steam wand knob closed to pump water through the puck and brew espresso.

3) if you want to steam milk, then flick the steam button and wait for the machine to heat up to the higher steam temp. When the heating light goes out, do not touch any of the switches, just turn the steam knob to release steam through the wand.

4) flick the steam to “off” and wait for machine to Coll back down to brewing temperature. You can expedite this by flicking the brew button to pump water through the brewhead. Initially steam will come out then water later once cools below boiling.

Link to post
Share on other sites

The procedure having all 3 switches down (ON) is for priming the system IF you have an air lock. From the video you do not.


To brew coffee, the L/H switch should be down =(ON) but no flow = this is in the maintaining heating mode.


When you are ready to brew coffee, the R/H switch should be down, this will operate the pump and water / coffee should come from P/F.

If it does not, it is most likely the solenoid valve is blocked or partially blocked which will require a strip down.

If the S/valve is blocked it will not matter how many times you D/scale the S/valve will need dismantling and cleaning.

Link to post
Share on other sites

Really really really appreciate the replies (especially since it is all good news, I feel slightly silly but mainly delighted I’m finally ready to get down to business!)


You guys are the best - thanks a million!

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • About
    Coffee Forums UK is the UK's premier coffee forum Started in June 2008 by Glenn Watson, we now have more than 24000 mainly UK based members, and welcome more than 3000 members and visitors from around the world each day! With strategic investment and digital expertise from the Jackson Lockhart team (Tait Pollack and Adam Bateman), we are taking Coffee Forums UK to the next level, and are delighted to share the journey with you.

    New Members:
    We are often referred to as the friendliest forum on the web and we look forward to welcoming you onboard. Please read our Terms of Use. We stick by them, existing members please familiarise yourselves with them.


    Coffee Forums Media Kit

    Click Here To Buy Advertising Space 
    £100 p/m when paid yearly, up-to: 690000 banner impressions per month!



    Become a friend of CFUK
    Buy Us A Monthly Coffee (massive thank you!) 


    Donate / Sponsor

    Click Here To Donate (big thank you!)

    Get Your Supporter Badge Today (per year)


    Coffee Forums Logo

  • Create New...