Results 1 to 14 of 14

Thread: Isomac Tea Problem

  1. #1
    Junior Member
    Join Date
    Jul 2012
    Posts
    3

    Isomac Tea Problem

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

    First post, in need of help. I've search extensively but may not be searching for the right parameters.

    I've had my Isomac Tea for about 3 years. Worked really well until the last few days. I've been using bench-top filtered water. From what I have read bench-top filtered water is not as good as I had presumed.

    Problem is that it seems to lack water volume/flow on the group.

    When I pull the lever to the full up (horizontal) position with the blind group installed it takes a good 28 seconds before the guage goes from 2 bar to 10bar on the right hand guage. To clarify it goes nowhere for 25 seconds then from 2 bar to 10 bar quite quickly. When I close the lever the resultant pressure release is aurally much less than before.

    If I pull a shot with even coarsely ground coffee it dribbles out as if I had used too fine a grind and heavy tamping.

    I am very happy to provide further info if someone needs it to hopefully diagnose the problem.

  2. #2
    Senior Member
    Join Date
    Mar 2011
    Posts
    609
    Sounds like you might need a descale, or maybe something is lodged in the gigleur (eg scale) which is blocking her up.

    If you do a search for "scale e61" or "descale e61" you'll find lots of help as there are lots of threads outlining how to descale your machine.

    The other thing you'd want to do is check the gigleur for blockage. Remove the mushroom (the big nut ontop of the group head), but be careful as the spring will make it jump out at you once it's loose. If it has white crusty chunks on it it needs a descale so do that. Carefully take out the little mesh tube and put it somewhere where it wont get bent. Get a socket wrench that's the right size, and very carefully remove the little nut that's down inside the group (the gigleur). You might need some needle nose pliers to get it out once it's loose, again be careful. Get a pin and ensure the tiny hole in the nut is clear. When you put the gigleur back in, don't over tighten it as it might break (like mine did).

    Search as above and you'll find lots of help.

  3. #3
    Site Sponsor coffee_machinist's Avatar
    Join Date
    Jun 2011
    Posts
    683
    Graham, your problems in order of likelihood I think are as follows:

    1: Nackered pump or not drawing water from the tank correctly (replace tank filter or replace pump or both)

    2: Water loss from the heat exchanger through the group brew valve, if it drips.

    From the symptoms you describe I think it's unlikely to be scale buildup, but you could remove the top nut from the group (with the machine off and cold) and inspect, if you want to eliminate scale from the equation.

  4. #4
    Junior Member
    Join Date
    Jul 2012
    Posts
    3
    Thank-you Gentlemen for your prompt replies.

    I'll investigate all aspects mentioned however I have a little bit more info that may be relevant.

    I now realise that I made an erroneous assumption. Am I correct in my (new) belief that the water that comes out the E61 and into my coffee cup was in the water reservoir only moments before being heated by the HX and pumped through the group? While trouble shooting and looking at the return water tube flow I noticed that the filter on the bottom of the water supply tube was surprisingly contaminated. If my assumption is correct could it simply be a blocked filter?

    I'm not going to run it without a filter to test my theory, I'll get a new filter on Monday and report back. If that fails I'll start the more complex trouble shooting.

    Thanks and regards,
    Graham

  5. #5
    Junior Member
    Join Date
    Jul 2012
    Posts
    3
    Sorry about the delay in reporting back. Busy week.

    By replacing the clogged supply tube filter all the problems went away. I didn't notice it at the time but the pump was also making a very slightly funny noise which went away when I replaced the filter, I assume this was as caused by suction pressure on the back side of the pump.

    Thanks for the comments, luckily for me this one was only a $5 fix.

  6. #6
    Member
    Join Date
    Jun 2011
    Posts
    38
    hi all,

    sorry to drag up an old thread but this is happening to me so i figure it's better to continue this thread.

    I get dribble of coffee when i pull a shot now. Even with a course grind and light tamp.

    when i pull the leaver without the PF in for 30 sec i get around 200ml of water coming out of the grouphead. I get 250ml from the vibrating pump.
    pressure hits 9bar when pulling a shot with a blind filter in.
    Does this sound like the pump is functioning ok?

    I've descaled the machine 3 times and water is still 200ml for 30 seconds out of the grouphead .
    I've pulled the grouphead apart, cleaned the mushroom, checked the Gigleur for blockage and checked the Gigleur Screen.
    The mushroom had lots of scale so that was removed. (rubber ring seal on the mushroom looks a bit flattened, not sure what would happen if this seal was leaking)

    Dismantled the OPV but there was no blockage.
    When i wind in the OPV in and pull the leaver with a blind filter i get 14-15bar so i'm guessing the pump is ok????
    Can a damaged/dying pump give good pressure but crap volume?

    Strangely i don't have a Priming Valve.
    Could this be my problem? Can u damage the pump without one?

    One-way Valve was dismantled and checked. No problem here either.

    I don't have a in-line tank filter and ingress hose to pump is not blocked.

    May not be relevant but notice it's slow to build up pressure when pulling a shot. it can take up to 5-10sec before i get any pressure at all, then it hits 9bar quite quickly after that.
    A couple of times when i've pulled a shot with the blind filter...afterwards the pressure stays at 9bar. Even when i've taken out the PF. The pressue drops back to nothing again when i pull the leaver with no PF in.
    Sounds like some sort of blockage???


    any help would be great.

    thanks guys

  7. #7
    Senior Member
    Join Date
    Mar 2012
    Posts
    1,275
    Quote Originally Posted by Pawnii View Post
    hi all,

    sorry to drag up an old thread but this is happening to me so i figure it's better to continue this thread.

    I get dribble of coffee when i pull a shot now. Even with a course grind and light tamp.

    when i pull the leaver without the PF in for 30 sec i get around 200ml of water coming out of the grouphead. I get 250ml from the vibrating pump.
    pressure hits 9bar when pulling a shot with a blind filter in.
    Does this sound like the pump is functioning ok?

    I've descaled the machine 3 times and water is still 200ml for 30 seconds out of the grouphead .
    I've pulled the grouphead apart, cleaned the mushroom, checked the Gigleur for blockage and checked the Gigleur Screen.
    The mushroom had lots of scale so that was removed. (rubber ring seal on the mushroom looks a bit flattened, not sure what would happen if this seal was leaking)

    Dismantled the OPV but there was no blockage.
    When i wind in the OPV in and pull the leaver with a blind filter i get 14-15bar so i'm guessing the pump is ok????
    Can a damaged/dying pump give good pressure but crap volume?

    Strangely i don't have a Priming Valve.
    Could this be my problem? Can u damage the pump without one?

    One-way Valve was dismantled and checked. No problem here either.

    I don't have a in-line tank filter and ingress hose to pump is not blocked.

    May not be relevant but notice it's slow to build up pressure when pulling a shot. it can take up to 5-10sec before i get any pressure at all, then it hits 9bar quite quickly after that.
    A couple of times when i've pulled a shot with the blind filter...afterwards the pressure stays at 9bar. Even when i've taken out the PF. The pressue drops back to nothing again when i pull the leaver with no PF in.
    Sounds like some sort of blockage???


    any help would be great.

    thanks guys
    Can we assume you have replaced the filter on the pump feed line in the tank ?
    and the shower screen etc ?

    200ml in 30 sec seems to be ok

    slow pressure build is normal on these E61 groups..its the pre-infusion chamber filling.
    Retained high pressure after removing the PF is NOT normal.. initial thought is possibly a dud gauge or blocked gauge capilliary tube?

    Have you stripped & rebuilt the lower part of the group ?

  8. #8
    Member
    Join Date
    Jun 2011
    Posts
    38
    hi Blend52,

    yes i've tried all this without the filter on the pump feed line in the tank.
    I also removed the Shower screen to check it, all is good.

    Stripped and rebuilt the lower part of the group as well. it seems to seal and drain as normal.

  9. #9
    Member
    Join Date
    Jun 2011
    Posts
    38
    Update:

    Hi all. My problem hasn't gone away and is doing my head in.

    I took a chance and changed the vibrating pump. I now get good volume of water out of the grouphead when pulling through an empty PF. (about a cup & and a half over 30secs)
    ....but when i pull a shot of coffee it just dribbles out and afterwards the pressure stays up around 8bar. When i remove the PF and pull the lever the pressure drops back down to 2bar (normal).

    What could be doing this???

    please help!

  10. #10
    TC
    TC is offline
    .
    Join Date
    Oct 2004
    Location
    Melbourne
    Posts
    14,665
    Wet steam too? Solenoid issue?

  11. #11
    Member
    Join Date
    Jun 2011
    Posts
    38
    steam works perfectly.

  12. #12
    TC
    TC is offline
    .
    Join Date
    Oct 2004
    Location
    Melbourne
    Posts
    14,665
    Hi Pawnii,

    I agree that the numbers all sound pretty normal.

    A heads up though. Removing the scale from the mushroom doesn't descale the machine and in fact is not a good thing. The mushroom acts as a "window" into the machine for a technician.

    In my opinion, you need a descale and it needs to be done properly. There are instructions around and you will need to force a boiler fill to do the job right. I think it's a job for a technician. In addition, a competent one will be able to Scace your machine at the same time. It may be that you just have a batch of coffee which requires a bigger than normal adjustment of your grinder.

    Cheers

    Chris
    Last edited by TC; 7th July 2013 at 05:39 PM.

  13. #13
    Member
    Join Date
    Jun 2011
    Posts
    38
    Thanks Chris.

    I have descaled the HX machine properly. Lifting the water level probe and forcing it to over fill. I even waited 2hr between flushing 3 times with Caffetto Restore descaler.

    I have recently just changed beans so that could explain why it's struggling to pull but it doesn't explain why the pressure stays at 8bar after extraction.

  14. #14
    Junior Member
    Join Date
    Mar 2011
    Posts
    2

    Wink Thanks for the post

    Quote Originally Posted by GrahamH View Post
    Sorry about the delay in reporting back. Busy week.

    By replacing the clogged supply tube filter all the problems went away. I didn't notice it at the time but the pump was also making a very slightly funny noise which went away when I replaced the filter, I assume this was as caused by suction pressure on the back side of the pump.

    Thanks for the comments, luckily for me this one was only a $5 fix.
    I am very thankful for this post. I have been having the same problem with my Isomac Mondialle. After 3 years of good operation my pump wouldn't seem to hold pressure and only started to climb to 9bar after about 30 sec. So after doing much research, it was this thread that caused me to look at the water intake filter. I found a heap of stuff clogging it up and having pulled it all out my machine is now back to how it should be.


    Cheers



Similar Threads

  1. Isomac pressure problem
    By Fabio in forum Brewing Equipment - Pointy End ($1500-$3000)
    Replies: 2
    Last Post: 27th July 2012, 07:41 PM
  2. Isomac Tea II or older Isomac Mondiale?
    By bean_roasting in forum Brewing Equipment - Pointy End ($1500-$3000)
    Replies: 21
    Last Post: 3rd June 2010, 12:47 AM
  3. Isomac Tea II
    By drac in forum Brewing Equipment - Pointy End ($1500-$3000)
    Replies: 12
    Last Post: 10th March 2010, 07:05 PM
  4. Isomac giadia problem
    By morningshot in forum Brewing Equipment - Entry level (sub $500)
    Replies: 2
    Last Post: 13th February 2007, 02:34 AM

Tags for this Thread

Posting Permissions

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