Results 1 to 11 of 11

Thread: Gaggia classic with heavy scale

  1. #1
    Junior Member
    Join Date
    Mar 2006
    Posts
    5

    Gaggia classic with heavy scale

    Gene Cafe Coffee Roaster $850 - Free Beans Free Freight
    Hi,

    My 5yr old gaggia classic recently clogged up. Cleaning solutions had no effect so I disamantled it and found lots of scale and crap clogged the solenoid leading to the group head. Upon reassembly everything works ok again BUT ....

    The Water flows properly again but when I looked at the boiler (aluminium I believe) I found it had heavy deposits of scale and was quite extensively pitted and eroded. Further I find that any water flow leaves very small amounts of scale in the cup. Ive run cleaner solutions through the reassembled machine again and again but it still seems to have scale residue.

    The water tastes ok, and perhaps the ground coffee will contain the scale so it does not get into the cup but I am concerned whether this is normal ... or is it time to get a new boiler and does anyone know what a boiler actually costs?

    thanks in advance for any advise,

    Hugh

  2. #2
    Senior Member robusto's Avatar
    Join Date
    Feb 2005
    Posts
    2,648

    Re: Gaggia classic with heavy scale

    I have read many reports that Gaggias with their aluminium boilers do corrode. And one retailer has abandoned them for that reason.

    Perhaps you should remove the boiler again, dismantle the element, then scrub the boiler, and soak it and the element in a bath of citric acid until they gleam.

    If the pitting is very deep, i.e., almost through the wall, will the boiler safely hold steam under pressure? Worth considering.

    Robusto


  3. #3
    Junior Member
    Join Date
    Mar 2006
    Posts
    5

    Re: Gaggia classic with heavy scale


    Thanks Robusto (for the amazingly quick response too!),

    Good suggestion ...

    > dismantle the element
    Do you mean remove the heating elements from the sides of the boiler? I wasnt sure that was possible so I left them on whilst I scrubbed it out with a bottle cleaner.

    > soak it and the element in a bath of citric acid until they gleam.
    Is citric acid something you can get from the local hardware (Bunnings)?

    thanks,

    Hugh

  4. #4
    Junior Member
    Join Date
    Mar 2006
    Posts
    5

    Re: Gaggia classic with heavy scale

    aside - I dont think the pitting is so extensive that it will not hold pressure but frankly I was quite amazed at how badly the corrosion was. Though the gaggia has been good to me I think Id avoid it again for this reason alone.

    Hugh

  5. #5
    .
    Join Date
    Aug 2004
    Posts
    2,312

    Re: Gaggia classic with heavy scale

    There are a couple of points to consider with

    a) scale, and
    b) aluminium corrosion.

    In a boiler, scale builds to form a HARD build up that does not escape. the build up is so hard that you would have to chip away at with a cold chisel to remove and in so doing, could do more damage in trying to remove it than the scale build up ever could. The HARD scale build up that we see in just about everything DOES NOT cause any harm, despite what is commonly and cyclicly regurgitated around on the net....as already stated above it simply coats the inside of boilers and passages with HARD build up and as far as we can ascertain, remains inert.

    In large boilers we dont necessarily bother trying to remove it unless it is causing some kind of real mechanical obstruction to flow (ie blocking something) or to some other part of the mechanicals that we need to get at.

    The other garbage that we see in aluminium boilers and that DOES also block things up but perhaps more effectively than scale because it is NOT *HARD but seems to form a sludgy paste, *is simply aluminium corrosion (aluminium oxide?). It manifests as a cheesy white substance and is indeed the reason why many professional espresso machine traders dont service the above brand.

    Lastly you also get "sludge" from unfiltered water. The three of them mixed together can form a rather interesting lot of garbage in your boilers.

    Having said (written) all the above, it is not uncommon to find small pieces of "grit?" in the water after descaling operations have been conducted.

    If the stuff gets through the shower plate (top filter) in the group then the particles must be incredibly small which probably means....the stuff you are seeing probably didnt come through the group at all and is therefore just stuff that is being dislodged externally (to the group) from the area where the group handle slots into the group (called the "group ring")...in which case a thorough mechanical cleaning (brushing with a stiff brush???) of the group ring area may be in order...or.......a great deal of flushing.

    So there is more to this than meets the eye.

    The above are but a quick & random kind of pick of my thoughts and they are of course open to discussion but I will repeat...anything that actually gets through a shower plate has to be minute or it would effectively block up the shower plate...you could try removing the shower, then flowing some water through the group to see if you still get the same stuff through..........In 99% of cases, substances that clients say are coming through the group actually do not and originate externally to the flow from the group.

    I personally, like domestic machines with brass boilers....they might get a build up of scale inside, but they dont get that cheesy aluminium corrosion in them, and they are FAR LESS prone to blockage over longer periods of time.

    There are others ways of looking at this for example.........a $500.00 * coffee mahcine that has lasted 5 years is technically "written off" in terms of what it has returned to you for the original investment...so you could, if your fiscal partner approves, hpop into a new machine of slightly different construction and you can then stop worrying about what long term ingestion of aluminium corrosion does to the insides of the human body!

    regardz,
    FC.



    *

  6. #6
    Senior Member robusto's Avatar
    Join Date
    Feb 2005
    Posts
    2,648

    Re: Gaggia classic with heavy scale

    Good post, Freshcoffee. *My understanding of the negative effect of scale build up is that in the most brutally severe cases, the scale effectively takes up most of the space inside the boiler. But that is very severe indeed.

    But the most common problem is that the scale (calcium and lime) on the element begins to act as an insulater ---obstructing the transfer of heat from the element to the surrounding water. *

    If you have an electric jug, peer into it and you will see the rusty-coloured deposit on the element and the base of the jug. *That will give you a good indication of how prevalent hard water is in your water supply.

    Citric acid is used in cooking --- very readily available in supermarkets, often in a shaker container like salt.

    I suggested removal of the element simply to faciliate the scrubbing (with a kitchen steel scouring pad).

    Robusto

  7. #7
    Junior Member
    Join Date
    Mar 2006
    Posts
    5

    Re: Gaggia classic with heavy scale

    You guys rock :)

    Yes there was a lot of sludge/paste which I agree is probably the Al. corrosion. I could scratch away at the boiler walls.

    The small metallic particles coming through are very very small and I see them accumulating at the bottom of a white cup ... a bit like I am prospecting.

    However that said Ill try and clean it out again and then print this out and use it as an excuse to get that Silvio :)

    thanks again guys for a very informative response,

    best regards,

    Hugh


  8. #8
    Senior Member robusto's Avatar
    Join Date
    Feb 2005
    Posts
    2,648

    Re: Gaggia classic with heavy scale

    If you are happy with the machine, Hugh, irrespective of its age, continue using it. A good clean and a few cents of citric acid is a far cheaper solution to an upgrade.


    Robusto

  9. #9
    Junior Member
    Join Date
    Mar 2006
    Posts
    5

    Re: Gaggia classic with heavy scale

    Quote Originally Posted by robusto link=1143062467/0#1 date=1143063385
    ... in a bath of citric acid until they gleam.
    Hi Robusto,

    Have you any suggestions on where to buy citric acid? Perhaps a brand name? Ive tried Coles, the chemist, the health food store in the cleaning product sections. Im on Northern Beaches in Sydney so the store have a good range of products. Admittedly I havent tried Bunnings yet but knowing the extent of the product range at Bunning being able to quote a brand name will help lots when I ask the staff.

    thanks,

    Hugh

  10. #10
    Senior Member robusto's Avatar
    Join Date
    Feb 2005
    Posts
    2,648

    Re: Gaggia classic with heavy scale

    Not sure Bunnings is the right place to buy citric acid -- its more of a supermarket range, like baking soda and other cooking ingredients.

    I use McKenzies Citric Acid, it comes in a 75 gram container with a rotating cap with various size holes, like a salt or pepper shaker. But any brand will do.

    Its made by Ward McKenzie in Altona Victoria. They have a web site.

    Hope that helps,


    Robusto

  11. #11
    Senior Member
    Join Date
    Aug 2005
    Posts
    1,530

    Re: Gaggia classic with heavy scale

    Behmor Brazen - $249 - Free Freight
    Citric acid is always kept near the baking goods section of a supermarket. When you see stuff like food colouring, 100s and 1000s, cake mixes and icing, youre in the right place.



Similar Threads

  1. scale deposits in my water- Gaggia coffee deluxe
    By kierent in forum Brewing Equipment - Entry level (sub $500)
    Replies: 4
    Last Post: 2nd May 2012, 12:41 PM
  2. Replies: 6
    Last Post: 15th March 2012, 09:20 PM
  3. Gaggia Classic portafilter and GAGGIA PROTEO ROMANZA
    By cazby in forum Brewing Equipment - Midrange ($500-$1500)
    Replies: 0
    Last Post: 24th October 2011, 06:50 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •