Page 1 of 6 1 2 3 ... LastLast
Results 1 to 50 of 279
Like Tree1Likes

Thread: Upgraditis: 2-group Grimac Commercial

  1. #1
    Senior Member
    Join Date
    Feb 2005
    Posts
    2,574

    Upgraditis: 2-group Grimac Commercial

    If *the upgradeitis bug bites, let it bite deep. Go all the way. *
    Hence, my new used Grimac Eclisse 2-group commercial machine has finally arrived.

    Getting it to its temporary home on the kitchen bench has taken two weeks of stress -- beginning with bidding on that evil, evil auction site. *It was supposed to be a pickup only -- no shipping -- from Sydneys nothern shores, to Melbourne. But if I could arrange a courier, that would be OK.

    Then came two days trying to find an interstate courier. Finaly settled on one, but under no circumstances would they pick up a machine which wasnt securely packaged.

    Negotiations with the seller to find a big box, but that proved fruitless as the machine was too big and heavy for her to package.

    It weighs 70 Kg, *is 510 mm wide by *530 deep by 440 high.

    One company was very happy to collect it, package it in a liquid styrofoam which expands around the machine shape when dry, then courier it to my home. For $260.

    But I found another company *whod do it for $100 with ordinary packing.... * Great. Except that the trucking company it uses lost my yet-unseen new toy which when new costs around $4000.

    For 7 whole days it has been lost, and I just about gave up hope until it unexpectedly arrived today. *I will never be dealing with this trucking company again.

    With the help of my wife and daughter, we lifted it up steps, dragged it along the carpet and unpacked it.

    It was nicely packed with foam bits and pieces everywhere, now making one hell of a mess on the floor.

    [img]NOTEBOOK//Desktop//grimac pix//packing mess.JPG[/img]

    We then lifted it onto the bench.

    First appearences.

    Looks good, stainless steel *everywhere expect for the plastic left and right covers.

    [img]C://Documents and Settings//Owner.NOTEBOOK//Desktop//grimac pix//IMG_1334.JPG[/img]

    Very easy access to the internals by removing a couple of screws here and there and lifting off steel cover plates.

    It is somewhat dirty under the drip tray. Under the bad evening light it even looked like rust, but a quick wipe and it was merely coffee grounds on pristine steel body parts.

    It has a copper boiler, 5 litres I believe. *With a rotary pump. Cant wait to hear that humming.

    A good clean up is in order, then will come the plumbing to mains supply and for waste water, *and a 15 amp dedicated power circuit.

    For now, time for a coffee break from my faithful Silvia.

    --Robusto





  2. #2
    Senior Member
    Join Date
    Mar 2006
    Posts
    167

    Re: Upgraditis: 2-group Grimac Commercial

    Congrats!

    Can you send me the details of the company that was willing to pack it for you, im considering a machine up that way too. :)

  3. #3
    Senior Member
    Join Date
    Jul 2006
    Posts
    3,495

    Re: Upgraditis: 2-group Grimac Commercial

    Hey Robusto....

    wheres the picture?....

    Im waiting to drool over my keyboard.....

  4. #4
    Senior Member
    Join Date
    Jul 2006
    Posts
    3,495

    Re: Upgraditis: 2-group Grimac Commercial

    Ah.... much better than the photo of the packing!

    Yep looks good.... welcome to the commercial coffee machine club...

    If you have any queries Im sure those with similar machines can help you out.

    Now to fire her up and start the checkout - or are you going to do a strip and rebuild?

  5. #5
    Senior Member
    Join Date
    Feb 2005
    Posts
    2,574

    Re: Upgraditis: 2-group Grimac Commercial

    Thanks, Java B. I will certainly need help with pressurestats etc.

    At this stage, I will clean it, give it a close inspection. Get some new group seals as a matter of course. I dont know whether it will require a rebuild -- but you never know. It is a volumetric, so hopefully all the electronics work.

    What surprised me was the uncluttered interior, with plenty of space to swing a spanner.

    Takeaim: I have sent you a PM with names.

    --Robusto

  6. #6
    Senior Member ozscott's Avatar
    Join Date
    Jun 2006
    Location
    BRISBANE
    Posts
    1,917

    Re: Upgraditis: 2-group Grimac Commercial

    Looks great Robusto...I have a possible commercial two group on the horizon from a mate of a mate so your wetting my appetite for new toys!!

  7. #7
    Senior Member
    Join Date
    Feb 2005
    Posts
    2,574

    Re: Upgraditis: 2-group Grimac Commercial

    The biggest problem with this toy is its considerable size. Am/was planning to install it where Silvia sits next to the kitchen sink, but may prove to be a very tight squeeze. Alternatively, the breakfast bar bench on the other side, but that will require a major, major plumbing operation.

    Or, dont plumb it, run it off a 20 litre water container. But will the pump sel-prime and suck up water from over a metre below?

    Decisions. Questions.

    And why do I feel pangs of guilt, having just made an espresso for me and lovely latte for my wife from Miss Silvia who doesnt know shes about to be two-timed.

    --Robusto

    --Robusto

  8. #8
    Senior Member
    Join Date
    Jul 2006
    Posts
    3,495

    Re: Upgraditis: 2-group Grimac Commercial

    Robusto

    I think you will find it is a 10 litre boiler.....

    Yep, commercial machines have lots of room inside and are easy to work on.

    At the risk of telling you how to suck eggs ::)

    The main switch on most commercials is 2 stage. The first activates the electronics including the auto fill circuit for the boiler...... make sure that the water level in the boiler is correct before switching to the second stage - which activates the heaters.... Not enough water to cover the heaters.... and one set of burnt out heaters.... :(

    Also make sure that the auto fill does in fact switch off at the correct level - too much scale on the level probe and it just keeps filling (until the relief valve vents water over everything) :(!!!

    Re plumbing in Vs running from a reservoir.. It depends on the type of pump. My La Cimbali needs positive pressure - about 3.5 Bar - on the supply - no reservoir for me! Some pumps (procon for example) are happy to draw water from a reservoir..... this is more likely with a single group than your double - but it depends on the pump. And plumbed in is just sooooooooo much more convenient :)

    Let us know how you go.

  9. #9
    Senior Member
    Join Date
    Feb 2005
    Posts
    2,574

    Re: Upgraditis: 2-group Grimac Commercial

    Thanks again, Javab, I appreciate your most valuable input and will call upon your knowledge more as if you dont tire of what I am sure will be endless questions.

    So far, Ive noticed that the glass water level tube is broken. Ive removed it and will probably also need rubber seals for where it is a sliding fit into large nuts.

    There appears to be --suprise suprise --scale on the copper tubes from the boiler to the glass indicator, so the boiler will be no better.

    Im tossing up whether I shoudl outlay $150 or so -- is that what a professional service costs? -- or just plod on myself. A descale was always going to be top of the list anyway.

    I am pretty good at fixing things, most things.

    So far, impressed with the build, very soild, very good thick copper pumbing throughout, no silicon tubes and circlips.

    Fairly sure the boiler is 5 litres, though I know some Grimacs-- the slightly wider ones like the Ten, and Victoria -- come with 10 litre boilers. (Its roughly 160 ml diameter by 240 ml long)

    Chris (2muchcoffee) will be pleased to know there were no cockroaches nesting away inside!


    --Robusto


  10. #10
    Sleep is overrated Thundergod's Avatar
    Join Date
    Jul 2006
    Location
    Sydney
    Posts
    10,494

    Re: Upgraditis: 2-group Grimac Commercial

    Im so glad it arrived.
    You must have been beside yourself.

    Good luck on the way forward.

  11. #11
    Senior Member
    Join Date
    Jul 2006
    Posts
    3,495

    Re: Upgraditis: 2-group Grimac Commercial

    robusto...

    Only too pleased to help you get her up and running .... so fire away when you need to.

    Yeah, you have the compact.... I assumed it was the larger version which is 10L ..... yours has the 5L boiler.

    You can descale the boiler yourself, but dont try to do it in situ (by pouring citric acid down the safety valve opening..... you will need to strip it down and descale whilst the boiler is open so you can make sure you have removed all the bits (you tend to get more scale build up around the openings and the corners of the boiler etc.....)

    And dont forget to do the heat exchangers at the same time.... they are also normally full of scale.

    Check the water deficit from the groups.... if too low you will either have blocked group filters or blocked group injectors (I replaced both of these on mine as a precaution) .....

    To test the pump have both groups running and check the delivery pressure on the gauge.... it should be steady at about 9 bars..... if it fluctuates quite a bit.... the pump is probably on the way out......

    Commercial cleaning is probably going to cost quite a bit more than $150.... but if you do the strip down and rebuild..... and just get them to do the descale..... you might come in well under that. I did it all myself- and including replacement bits - it probably cost about $80 all up- group seals, boiler seal, heat exchanger seals, group filters and injectors. :) Thank heavens for CoffeeParts ;)

  12. #12
    Mal Dimal's Avatar
    Join Date
    Oct 2004
    Location
    Warwick, QLD
    Posts
    15,386

    Re: Upgraditis: 2-group Grimac Commercial

    Good pickup there Robusto,

    That is one serious espresso machine, and looks very presentable too. Will be very interesting to track your refurb job as time goes along.... lots of piccies please ;D,

    Mal.

  13. #13
    Senior Member
    Join Date
    Feb 2005
    Posts
    2,574

    Re: Upgraditis: 2-group Grimac Commercial

    Thanks Thundergod, JavaB and Mal. Its reassuring to know that I have the moral and technical support of my fellow coffeesnobs in this project.


    I will definitely descale myself. I have been quoted a ridiculous $400 -500 for a professional job, plus parts. So JavaB, Ill take your advice and unbolt the numerous pipes from the boiler, remove it and descale.

    Im now off to get some parts.

    The chrome and stainless steel panels have come up very well. Even the copper boiler and piping looks good, but copper being what it is will oxidise to a dull finish again.

    [img]C://Documents and Settings//Owner.NOTEBOOK//Desktop//rear view.JPG[/img]


    --Robusto




  14. #14
    Senior Member
    Join Date
    Jul 2006
    Posts
    3,495

    Re: Upgraditis: 2-group Grimac Commercial

    robusto,

    Once you have replaced the water level tube I would fire her up (connected to mains water at least for the test) and check out the functions.....

    You really want to get a handle on the magnitude of work required before investing too many of your hard earned dollars - and time (thats the reason I like to see a used commercial machine working before purchase).

    The most important (read expensive!!) things to check are:

    The pump runs and produces a stable 9 bar pressure..... (you can generally test that by doing the boiler fill)

    Once the boiler fills, switch on the heaters and the boiler should produce about 1 bar of steam pressure (generally somewhere between 1 and 1.5 bar depending on the pressurestat setting).

    The on board "computer" functions correctly (you can get both groups to dispense water and the hot water outlet operates- if controlled by the computer rather than a tap).

    The brew pressure and steam pressure gauges both operate.

    If they all check out OK then thats the expensive bits out of the way. ;) ;D

    Then see how much water flows from each group during 30 seconds (without the PF) - should be about 400ml. If significantly less (and the pressure remains at 9 Bars....) then the group filter and or group jet is blocked- and will probably need to be replaced.

    If you have got this far without slashing your wrists.... smile :) :) its descale time!

  15. #15
    Senior Member
    Join Date
    Apr 2005
    Posts
    1,176

    Re: Upgraditis: 2-group Grimac Commercial

    Good one Robusto. A 5l boiler sounds nice and compact for home use. As someone who has just about come out of descale/clean rebuild process (I didnt type nightmare), Id thoroughly suggest a major rebuild.

    Heres a few points. For descaling, citric acid is pretty safe, but really works best in hot water. Be careful with other commercial descaling solutions like CLR, as they are sometimes hard to completely remove without leaving a tell-tale smell. Even after citric acid use, the copper will be porous and exposed and will need to be re-passivated. This is done by kepping the machine running and up to pressure for some days and periodically flushing the boiler contents.

    To get the compression fittings off without damaging the pipes or boiler (copper is a soft metal) give the spanner a tap with a hammer. The fittings often make a cracking sound before coming loose. Conversely, when putting the compression fittings back togather, dont over-tighten. The metal-metal seal works pretty well.

    Make sure you descale all the pipes as you usually find scale all the way back to the pump.

    When you rebuild the machine, carefully check each fitting for leaks. Also be aware that a couple of heating/cooling cycles may loosen some fittings, so be prepared to check a second time to be sure.

    JavaB gave some good advice on the check list once fired up. I love the way commercials can isolate the element. That way you can check most things wiuthout worrying about the element. However, before rebuilding the boiler with the element, try taking the element to a coffee tech place so they can test it with a high voltage leakage beastie. A standard multi-meter often wont spot an element prone to tripping an earth leakage detector.

    If youre going to all the trouble of pulling the thing down, then you may as well be sure that its all working when you put it back together.

    Good luck with the restoration.

    Cheers,

    Mark.

    PS Miss Silvia knew her time had to come...

  16. #16
    Senior Member
    Join Date
    Jul 2006
    Posts
    3,495

    Re: Upgraditis: 2-group Grimac Commercial

    Quote Originally Posted by Sparky link=1173088713/0#14 date=1173145012
    Good one Robusto. A 5l boiler sounds nice and compact for home use. As someone who has just about come out of descale/clean rebuild process (I didnt type nightmare), Id thoroughly suggest a major rebuild.
    And a 5l boiler will be a lot easier to clean than my 17l tank engine boiler was ;)...... a rebuild is definitely worth it in the end. :) :) :)

  17. #17
    Senior Member
    Join Date
    Apr 2005
    Posts
    1,176

    Re: Upgraditis: 2-group Grimac Commercial

    It looks like a sweet machine. Grimac uses the E61-type group, but the auto-dosing variant wont have any pre-infusion.

    The one concern with Grimac machies is that Coffeeparts doesnt stock parts, which is a bummer in terms of convenience.

    Maybe we should start a new club for people with 2 gr commercials?... 8-)

  18. #18
    Senior Member
    Join Date
    Jul 2006
    Posts
    3,495

    Re: Upgraditis: 2-group Grimac Commercial

    Quote Originally Posted by Sparky link=1173088713/15#16 date=1173153845
    The one concern with Grimac machies is that Coffeeparts doesnt stock parts, which is a bummer in terms of convenience.
    As I said in my post in the Coffee Machines list - try to get a second hand commercial for which CoffeeParts has spares.... their range, service and price are all great..... as is their technical assistance.

    Maybe we should start a new club for people with 2 gr commercials?... 8-)
    Yep, there are a few of us around now.....

  19. #19
    Senior Member
    Join Date
    Feb 2005
    Posts
    2,574

    Re: Upgraditis: 2-group Grimac Commercial

    Thanks again everyone: Heres an update.

    Grinders, in fairfield, Melbourne, contrary to rumours does stock, service and carry parts for all Grimacs. Thats where I went.

    I bought replacement group seals (only $2 each) and a new glass tube showing min/max plus a couple of grommets for where it slides into compressions nuts.

    All up, $48. Not bad so far.

    I descaled the boiler and heat exchangers with hot water and citric acid, forced through the heat exchangers and groups with a little sprayer. The water came out yellowish, which was a good sign the operation was working -- I hope that is what it means.

    Flushed clean water through boiler and heat exhangers.

    I removed and throughly cleaned and descaled some pipes, but not all.

    Reassembed everything, one small leak where Id forgotten to tighten a nut.

    This is where things go sour.

    Boiler pressure shows 1.1 bars. But there is no movement for the heat exhanger pointer, which remains at 2.2 bars.

    The left group volumetric buttons when pressed make all the right pump noises, but no water emerges.

    At first, water did come out of the right group, but now, nothing.

    Any suggestions? Is there any bleeding of the exchangers to be done?

    I havent removed the old group seals or removed and cleaned the shower screens yet.

    Could they be the problem? Perhaps lose scale in the works?

    Advice greatly appreciated.

    --Robustp

  20. #20
    Senior Member
    Join Date
    Feb 2005
    Posts
    2,574

    Re: Upgraditis: 2-group Grimac Commercial

    Cancel that!!

    Ive realised that one thing I havent, quite rightly, touched, is the electricals. I just went back and made sure all the ribbon cables and connectors were pushed well into one of black boxes". Well, they were lose. Perhaps that happened accidently when I was bolting and unbolting things to the boiler and groups.

    In any case....both groups are now producing water.

    So Ill keep flushing water through to get rid of all the scale and citric acid residue.

    Tomorrow, when things are cool, Ill attack the group seals.

    --Robusto

  21. #21
    Senior Member
    Join Date
    Jul 2006
    Posts
    3,495

    Re: Upgraditis: 2-group Grimac Commercial

    Robusto

    Ah, sounds like good progress being made.... and all is more or less working (certainly the expensive bits appear to be OK :) :) :) :)).

    Not too sure of your descaling regime though...... You really need to strip the boiler down or you can end up with bits of scale which come off - dislodged by the citric acid - but not totally dissolved.... and these float about until they find some nice place to come to rest..... and that nice place will generally block up some important valve, pipe, jet etc..... :(

    You might be lucky..... I hope you are. :-/

  22. #22
    Senior Member
    Join Date
    Jul 2006
    Posts
    3,495

    Re: Upgraditis: 2-group Grimac Commercial

    Quote Originally Posted by robusto link=1173088713/15#18 date=1173163257


    Boiler pressure shows 1.1 bars. But there is no movement for the heat exhanger pointer, which remains at 2.2 bars.
    Just a tip here....

    I had a similar problem..... it was scale in the pipe to the gauge and in the little "pin hole" in the coupling at the back of the gauge....

    Descaled the pipe and cleaned out the pin hole with of all things - a pin ::)(very carefully as there is a diaphragm at the end of the hole which can be easily damaged)..... cleaned away the powdered scale which I had dislodged..... reassembled.... and hey presto.... 5.1 Bar at rest (supply pressure) which rapidy increases to 9 Bar when the pump kicks in - all is good. :) ;D ;D

  23. #23
    Senior Member
    Join Date
    Feb 2005
    Posts
    2,574

    Re: Upgraditis: 2-group Grimac Commercial

    Thanks JavaB, when things cool down tomorrow the gauge will be looked at.

    My descaling wasnt the best, as you say.

    What I did was remove two pipes to the bottom of the boiler, and two at the top..

    First I flushed water through to dislode any loose material -- dont know how long this machine has been in storage.

    Then I put back the bottom pipes, and filled the tank with hot water and citric acid -- but did not run the mix throughthe system.

    I let it sit, and then removed the bottom pipes again *so the mixture with all its yellow crud could go through those holes only.

    Similar routine for the heat exchangers. *

    But now that I know the machine works, Ill descale again in-situ.

    At the moment it is not plumbed in --- its getting filtered water from a huge steel *kitchen pot. *So itll be easy to put citric acid into that.

    --Robusto

  24. #24
    Senior Member
    Join Date
    Feb 2005
    Posts
    2,574

    Re: Upgraditis: 2-group Grimac Commercial

    Another update.

    I spent 15 hours on the machine, and was so tired sleep was difficult.

    The inoperative pressure gauge. Unfortunately the problem is deeper than clearing the pump inlet with a pin.

    On dismantling it, it works similar to a dial thermometer with an expanding bimetal coil which in turn moves clockwork-like cogs.

    A tiny little arm connecting the coil to the rest of the works is broken. Im going to attempt to solder it, but dont like my chances. Even if I succeed, the calibration will probably be out.

    Could be that a new guage is in order.

    --Robusto


  25. #25
    Senior Member
    Join Date
    Jul 2006
    Posts
    3,495

    Re: Upgraditis: 2-group Grimac Commercial

    Robusto

    Now thats dedication! :o :o

    It takes quite a bit of time to undo the years of little (or poor) maintenance which most of these machines have had. Its a tribute to their makers that they have "soldiered on" for so long and still made great coffee.

    Its a pity about the gauge - I was more fortunate - but careful soldering should work. Not a lot of stress on that bit (unlike the person doing the restoration ;)).

    Many see these machines as a sledge hammer to crack a walnut.... but the taste of the walnut is just soooooooo good..... and the satisfaction that comes with knowing you restored it yourself - priceless!! :) ;D

    Not too much longer now.

  26. #26
    Senior Member
    Join Date
    Apr 2005
    Posts
    1,176

    Re: Upgraditis: 2-group Grimac Commercial

    I am impressed... pulling a pressure gauge apart is pretty serious business.

    New gauges should run about $70-$100 depending on who you get it from.

  27. #27
    Senior Member
    Join Date
    Feb 2005
    Posts
    2,574

    Re: Upgraditis: 2-group Grimac Commercial

    Pulling the gauge apart was a very simple operation -- two grub screws hold the cylindrical case to the internals.

    I think the skills of a clock maker would better serve the repair, however.

    Holding something the size of a 10 mm pin with 2 mm eyelets at each end and trying to position it is no easy task.

    In any case, after hours of fiddling around, I made a new part from a paper clip, hammering the ends to flatten them, and forming eyelets out of them. (it looks like a dumbell, but all flat)

    However, that hasnt solved the problem. The springy bimetal tube which expands according to pressure, pulls back too much so that the gauge pointer does not reset to zero.

    The RPM brand rotary pump is self-priming, and for now Ive now droped the intale hose into a 10-litre bottled water container which Ive filled with Brita filtered water.

    The pressurestat cycling on and off is quite a loud click. Probably accentuated by the covers being off the machine.


    But the main thing is that everything (except the pressure gauge) works, and there are no leaks.

    The group seals will have to wait. Too tired today. They do seal and Im warming her up for an espresso.

    --Robusto

  28. #28
    Sleep is overrated Thundergod's Avatar
    Join Date
    Jul 2006
    Location
    Sydney
    Posts
    10,494

    Re: Upgraditis: 2-group Grimac Commercial

    Quote Originally Posted by robusto link=1173088713/15#26 date=1173230327
    However, *that hasnt solved the problem. *The springy * bimetal tube which expands according to pressure, pulls back too much so that the gauge pointer does not reset to zero.
    Is it possible to rotate the face?

  29. #29
    Senior Member
    Join Date
    Jul 2006
    Posts
    3,495

    Re: Upgraditis: 2-group Grimac Commercial

    Quote Originally Posted by Thundergod link=1173088713/15#27 date=1173231290
    Quote Originally Posted by robusto link=1173088713/15#26 date=1173230327
    However, that hasnt solved the problem. The springy bimetal tube which expands according to pressure, pulls back too much so that the gauge pointer does not reset to zero.
    Is it possible to rotate the face?
    Generally the needle on most gauges is a press fit to the shaft and can be (carefully) rotated to set the zero.

    Also make sure you dont suffer from the same problem Mark has where - because there is no pressure on the water in the heat exchanger (normally at mains supply pressure)- the water in it will boil (being heated to 125C or thereabouts......) Mark has had this boiling water / steam flow back via the pump and into his reservoir... (not good for the pump either I would imagine :()

    Will also make for some interesting cooling flushes as the heat exchanger (normally full of water) will be dry!! :-/ :-/

  30. #30
    Senior Member
    Join Date
    Feb 2005
    Posts
    2,574

    Re: Upgraditis: 2-group Grimac Commercial

    Gulp. Thats an ugly thought. The Grinders technician said it was OK to run water from a tank. But on the other hand, I know some machines do want a head of mains pressure.

    I dont want my cooling flush to be the steaming part of coffee making!

    -Robusto

  31. #31
    Super Moderator Javaphile's Avatar
    Join Date
    Dec 2004
    Location
    Earth!
    Posts
    14,064

    Re: Upgraditis: 2-group Grimac Commercial

    Im not sure Im understanding all this talk of back pressure from the HX. Unless the brew solenoid has broken nothing from the HX will flow back into the system.

    The brew solenoid is between the water supply/pump and the HX. The HX is open to the atmosphere via the grouphead and the 3-way pressure relief valve. As the water in the HX boils away it will simply vent out of one of these two openings, not back into the water pipe and into the pump.

    Such is the case on the Cimbalis anyways. Is there something different about this machines design that would allow this to happen?


    Java "Confuzzled" phile

  32. #32
    Senior Member
    Join Date
    Apr 2005
    Posts
    1,176

    Re: Upgraditis: 2-group Grimac Commercial


    There is no brew solenoid in most of the commercials Ive seen (Bezzera, Faema, La Pavoni and a few others). The water to the groups is controlled by opening the 3-way valve to allow water from the HX to flow to the group.

    The 3-way valve will usually withstand a back pressure of between 12 and 15 bar before opening, so can act as an expansion valve for the HX. This only occurs if there is a check valve in the system (or a brew solenoid in your case), otherwise the pressure will force water back through the system towards the pump.

    These check valves are very small and simple and are not easy to spot, but they usually have an arrow indicating the flow direction.

    Any flow of hot water back to the pump is best avoided as it usually causes the pump much consternation (as I have found out).

  33. #33
    Senior Member
    Join Date
    Jul 2006
    Posts
    3,495

    Re: Upgraditis: 2-group Grimac Commercial

    All.

    The La Cimbali M20 I have also has NO brew solenoid - only the three way valve.

    Hence why the HX is pressurised (according to the diagram I have)

  34. #34
    Senior Member
    Join Date
    Feb 2005
    Posts
    2,574

    Re: Upgraditis: 2-group Grimac Commercial

    Took your advice, JavaB and "recalibrated" the pump pressure side of the gauge by removing the pointer and resetting it at zero. Funny, I tried to do that last night but couldt budge it. Today it came out readily.

    Unfortunately, it now doesnt budge. May need more calibrating. More on the gauge further down.

    Im still familiarising myself with the myriad of plumbing. Ive worked where the two heat exchangers are. How they are fed, and how the boiler is fed. How the volumetric plumbing circuit works (cold water between pump and heat exchanger). Why am I surprised by that? Cos I always imagined it measuring what goes in the cup, not the amount of water that flowed to the exchanger to achieve that!

    I havent dismantled the groups, but each appears to have only a three-way valve. Perhaps I should investigate further.

    I cant find specs for the Grimac Eclisse, but for the TEN compact, which is similar, the specs are for 0 - 4 bar water intake, so using my 10-litre container should not be a problem.

    There also appears to be some sort of pre-infusion.

    When I press the dose button, I hear the 3-way valve kick in for a second, and then it clicks shut, pauses, then away it goes again. That would be handy.

    Had a devil of a time working out why no water was pumping today after I replaced the pressure gauge.

    Hours of checks -- it turned out to be that because Id removed the line to the pressure gauge, the pipe needed bleeding of air.

    Its handy to learn and know these things to avoid future trial and hour groping in the dark.

    --Robusto

  35. #35
    Super Moderator Javaphile's Avatar
    Join Date
    Dec 2004
    Location
    Earth!
    Posts
    14,064

    Re: Upgraditis: 2-group Grimac Commercial

    Im afraid my description may have caused some confusion with its poor wording. The brew solenoid I refer to is, on machies equipped with one, the 3-way valve/solenoid with the pressure relief valve also being incorporated into the 3-way. :)


    Java "Hopes he cleared it up" phile

  36. #36
    Senior Member
    Join Date
    Feb 2005
    Posts
    2,574

    Re: Upgraditis: 2-group Grimac Commercial

    That clears it up, Javaphile.

    More pix.

    The machine may be a pretty site, but the massive 20 ml *power lead (with provision for 3-phase), the water supply hose, and the drain hose, arent. *

    I hope my wife doesnt want access to the cupboard underneath.

    This pic shows the temporary installation, with water supply alongside.



  37. #37
    Senior Member
    Join Date
    Apr 2005
    Posts
    1,176

    Re: Upgraditis: 2-group Grimac Commercial

    Robusto, pre-infusion sounds good, but youll need mains pressure to make it work well.

    I like the industrial look.

    Cheers,

    Mark.

  38. #38
    Senior Member
    Join Date
    Jun 2006
    Posts
    754

    Re: Upgraditis: 2-group Grimac Commercial

    When you guys plumb in the machine to a mains, do you get a plumber in or just do it your self and dig a hole in your kitchen bench? haha and how would you know how much pressure is in the mains so you know if you need a restrictor?

  39. #39
    Senior Member
    Join Date
    Feb 2005
    Posts
    2,574

    Re: Upgraditis: 2-group Grimac Commercial

    A plumber? Whats that?

    It doesnt take a tradesman with call out fees and hourly rate to use a hole saw on the bench top, and to use a spanner to install a T-junction where the cold water tap attaches to the wall.

    Flexible hoses are soooo easy.

    I would recommend isolating the machines intake via an inline tap or valve.

    The pressure reducer could be but probably wont be a problem. Im sure there are ways to convert how long it takes to fill a 10 litre bucket
    into pressure.

    --Robusto

  40. #40
    Senior Member
    Join Date
    Jul 2006
    Posts
    3,495

    Re: Upgraditis: 2-group Grimac Commercial

    Quote Originally Posted by robusto link=1173088713/30#38 date=1173256234

    The pressure reducer could be but probably wont be a problem. Im sure there are ways to convert how long it takes to fill a 10 litre bucket
    into pressure.

    --Robusto
    Nah....

    If you get your brew gauge working.... connect your machine.... slowly crack open the tap and watch the gauge climb.... mine got to 5Bar.... so sweet - no pressure regulator required!

    The plumbing in the machine can withstand 9 Bar... so no problem with a static measurement (just dont run the machine until you have checked the pressure is within the allowed range).

  41. #41
    Senior Member
    Join Date
    Feb 2005
    Posts
    2,574

    Re: Upgraditis: 2-group Grimac Commercial

    This raises an interesting question. Im reading on Alt.coffee that the pump pressure regulator has to be adjusted if there is no supplementary mains pressure -- i.e, supply is from a tank as I am using.

    Is that so, JavaB?

    Since my pressure gauge doesnt work, is there a way of calculating whether the brew pressure is 9 bar?
    Some sort of water deficit measurement?

    Im thinking something like the Ulka vibe pumps where if 250 mls bypasses the brew head and back into the tank that equates to 9 bars.

    Also...cooling flushes. how do you tell when enough water has been drawn? And is it drawn with portafilter in place, or without?

    --RObusto


  42. #42
    Senior Member
    Join Date
    Jul 2006
    Posts
    3,495

    Re: Upgraditis: 2-group Grimac Commercial

    robusto,

    The delivered pressure will drop a little without mains supply - but not much - as the regulator is on the output side of the pump.

    There is no easy way to measure the pressure as unlike the ulka where there are graphs for delivery volume Vs delivery pressure..... with a rotary pump once the regulated pressure is reached the output is shunted back to the input and the pump will maintain constant (well near constant) pressure from nil flow to about 2 liters per minute for my pump.....

    The actual delivery volume varies from pump to pump but the pressure will remain the same until you exceed that delivery volume.

    So you really need a gauge.

    Re cooling flushes - Mine needs about 200 ml if rested for >5 minutes. Basically I flush until there is no more hissing steamy water coming out..... leave it for a minute (whilst dosing).... then give a quick flush of about 50 ml.... lock and extract.

    The actual volume varies with the design of the group... but flushing until you have got rid of the steamy water is pretty universal.

  43. #43
    Senior Member
    Join Date
    Feb 2005
    Posts
    2,574

    Re: Upgraditis: 2-group Grimac Commercial

    Thanks JavaB. Hours go by before I make an espresso, so looks like Ill be going through much cooling water.

    Ive done a quick calculation of power consumption, and on this pretty warm day, the pressurestat cycles every 2 minutes, heating for 15 seconds.

    Were I to leave the machine around the clock, that equates to about 90 cents of electricity a day.

    Havent noted how long it takes to reach operating pressure from cold, and whether it is best to leave it off, and power it up say, 3 times daily.

    The element is 3300 watts.

    -Robusto

  44. #44
    Senior Member
    Join Date
    Jul 2006
    Posts
    3,495

    Re: Upgraditis: 2-group Grimac Commercial

    Robusto,

    Well my element is 4000W and it is on for about 10% of the time.

    It takes about 20 minutes to get a full head of steam from cold..... but about an hour for the temperatures to really stabilize.. (which is how long they turn them on before opening in a cafe).

    So for the first 20 minutes its flat out heating - which equates to over 3 hours of 10% use - times 3 times a day = 9 hours plus the extra half an hour each time at 10%..... 10.5 hours all up.

    Mine is on 24/7.... yeah it costs a bit more.... but I can walk up whenever I want and have a coffee.. (within about 1 minute from arriving on scene).... and my wife works shift..... and wants a coffee at weird hours.....

    and its just so convenient that way!

    EDIT: and I forgot... there is always hot water on tap... so the tea drinkers can have a cuppa when ever they want.... my son makes himself instant noodles etc.... it is even used to fill small saucepans.. all of which is a good idea- if you only use the boiler for steam- the only thing which leaves is pure water (the salts are left behind) .... by using the hot water tap you flush the boiler each time ;)

  45. #45
    Senior Member
    Join Date
    Feb 2005
    Posts
    2,574

    Re: Upgraditis: 2-group Grimac Commercial

    Yep, 10 per cent is what my calculation runs out to: 2.5 hours over a 24-hour period. The convenience factor is quite an important one.

    I would imagine there would be less stresses on the machine is it keeps a constant temperature and pressure, rather than go from stone cold to hot and back again.

    --Robusto

  46. #46
    Senior Member
    Join Date
    Jul 2006
    Posts
    3,495

    Re: Upgraditis: 2-group Grimac Commercial

    Quote Originally Posted by robusto link=1173088713/30#44 date=1173260953
    I would imagine there would be less stresses on the machine is it keeps a constant temperature and pressure, rather than go from stone cold to hot and back again.

    --Robusto
    Definitely true... the machine is all up to constant temperature, and just ticking over rather than full cycling several times a day - and they were designed to be left on - normally at least 12 hours a day.

    Im really pleased using mine that way, and no complaints from other members of the household ("She who must be obeyed" was a little worried at first - but now is one of the biggest users - and totally happy to leave it on.)...

  47. #47
    Senior Member
    Join Date
    Feb 2005
    Posts
    2,574

    Re: Upgraditis: 2-group Grimac Commercial

    Off to watch Extras now....

    But tomorrow Ill post descriptions of some extractions and lattes I made tonight. (Silvia, where are you girl....?)

    Ill hope to take some pix too.

    --RObusto

  48. #48
    Senior Member
    Join Date
    Apr 2005
    Posts
    1,176

    Re: Upgraditis: 2-group Grimac Commercial


    Robusto, if the pump was set up to work with a plumbed machine it will brew at too low a pressure on a tank (like 4-6 bar), as the bypass valve is set to open at a relative pressure difference between the input and output. So with a plumbed pressure of between 3 and 5 bar, the make-up difference is 4-6 bar, and hence the setting. For a tank the inlet pressure will be close to zero and the total pressure of the pump plus inlet will be just the pump setting.

    As JavaB said ther is no easy way to dial this in without a gauge.

    Anyway good luck with the brewing and may the red crema be with you.

    Cheers,

    Mark.

  49. #49
    Senior Member
    Join Date
    Feb 2005
    Posts
    2,574

    Re: Upgraditis: 2-group Grimac Commercial

    Thanks, Sparky.

    A gauge is obviously necessary -- Ive been quoted $200 for one. Ouch. Trying to source one cheaper, seing how for other machine types they are around the $80 mark.

    --Robusto

  50. #50
    Senior Member
    Join Date
    Jul 2006
    Posts
    3,495

    Re: Upgraditis: 2-group Grimac Commercial

    Ouch in deed Robusto....

    You cant get "an almost identical" one from CoffeeParts? Give Pedro a ring with the size and he might be able to help......

    The other option doesnt bare thinking about :( :(

Page 1 of 6 1 2 3 ... LastLast

Similar Threads

  1. Grimac 2 Group machine
    By Journeyman in forum Brewing Equipment - Midrange ($500-$1500)
    Replies: 6
    Last Post: 3rd March 2013, 09:05 PM
  2. Replies: 2
    Last Post: 4th December 2012, 11:27 PM
  3. Whats the Size of Group Seals for ExpoBar Megacrem 2 Group Commercial?
    By whitie8000@hotmail in forum Brewing Equipment - Extreme Machines ($3000+)
    Replies: 15
    Last Post: 22nd June 2011, 03:16 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
  •