Jump to content

Gaggia Classic - Loss of Steam Pressure


Recommended Posts

Posted (edited)

Morning Folks,

Have recently given my ten year old Gaggia Classic a bit of a refurb.  Replaced the stock steam wand with a Rancillio and also swapped out the steam valve for a new one as it was constantly leaking.

Everything works fine during the brew but there is now an issue with the steam.  Just before the steam light comes on, there is a loud rattle from inside the machine which dies away just as the boiler gets to temperature and the light comes on.  Ok, so I ignore this and steam the milk, but there is not the pressure and volume of steam that I used to get, making the foaming of the milk harder.  

Initially, I though the noise was water leaking from the boiler from the joint with the new steam valve and rapidly boiling on the surface metal but this doesn't appear to be the case.  Without the lid on, I can see that the rattling is air and water being quickly dispensed via the expansion valve, down the clear plastic pipe back into the tank, presumably causing a drop in steam pressure.

Any ideas would be appreciated,

TIA

Matt

Edited by mirkl
Link to post
Share on other sites
Posted (edited)
40 minutes ago, Blue_Cafe said:

Stuck OPV?

Could be - its not been serviced since I bought the machine.  With the new steam valve I guess the OPV is working harder as pressure is not being lost through the dripping wand.  May have caused it to jam.

I'll have it out tonight and report back

Thanks

Edited by mirkl
Link to post
Share on other sites

Well that didn't go well!

Took the OPV out and soaked in in citric - didn't look to crusty.  Put the OPV back in and electrocute myself on the steam thermostat (I know!).  

Anyway, machine powers on, water pumps through the group head.  Flick the steam switch and wait.  Boiler heating up but no steam light and now a slight burning smell.  Turn everything off and let it cool down.  Turn it back on, no power to pump or boiler.

I'm guessing I blew the steam thermostat when it gave me the shock.  The thermal fuse then blew because the boiler overheated as I waited for the steam. 

So I think I need a new steam thermostat and a thermal fuse and also a lesson in electrical safety.  Would you agree?

TIA

  • Sad 1
Link to post
Share on other sites
1 hour ago, mirkl said:

now a slight burning smell. 

You should be able to track down what it was - the thermal fuse is on top of the boiler so easy to see / smell if it was that.  Good luck. 👍

As an aside ...one  of the nice things about a PID is you can see if it is at the right temp or not.  Lights can be off for a number of reasons.

Link to post
Share on other sites
  • 3 weeks later...

Just jumping on this thread as I have exactly the same problem of dropping steam pressure, also with a new steam valve and Rancillo wand with a similar age machine. Just wondering whether you managed to solve the original problem Mirkl/Matt, not the problem involving A+E....

Link to post
Share on other sites

DLM.  Having damaged the thermostat and fuse with my previous misadventures, I decided to completely strip the machine down for a full service, boiler and all.

On reassembly , everything was functioning as normal and I suspect that a thorough clean of the boiler and OPV may have removed any particles that were causing a loss of pressure.

I've learnt tonnes about the machine's workings by doing this which has given me the confidence to undertake just about any future repairs. Would recommend.

  • Like 1
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.

Guest
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.

    Advertising

    Coffee Forums Media Kit

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

     

    coffee-subscription-mini.png

    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)

    image.png



    Coffee Forums Logo
     

×
×
  • Create New...