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  • hotshod
    replied
    Originally posted by coffee_machinist View Post
    Would have been nice to get a mention for the time spent on the phone the other day helping you narrow down the problem to the restrictor. Could well have saved you a lot of time and money chasing the problem elsewhere. Just sayin'....
    That was very poor form on my behalf, Rick "Coffee_Machinist" did in fact spend 10-15 minutes with me on the phone and directed me as to where I could find the damaged restrictor and spoke a lot of common sense about isolating the problem with my machine.
    I did send Rick a lengthy text message thanking him for his time and advice, plus outlining the results I achieved, and after 2 months of frustration I was very grateful.

    Post #17 Definitely should have made reference to the advice I received from Rick .....

    I would also suggest other CS members take a quick tour thru Ricks' website and check out his work with PIDs and other tasty restorations.

    The Coffee Machinist

    Greg

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  • coffee_machinist
    replied
    Would have been nice to get a mention for the time spent on the phone the other day helping you narrow down the problem to the restrictor. Could well have saved you a lot of time and money chasing the problem elsewhere. Just sayin'....

    Leave a comment:


  • TOK
    replied
    Hi there.

    the factory spec for that orifice is in fact 3mm, and I expect the material has over time and perhaps through the effect of heat expanded, resulting in a reduced orifice size. Good to know that by your own experimentation, you have ended up back at the factory spec.

    For what its worth I dont think it was a waste of money to have replaced the pressurestat. Once they start doing what you explained in your first post, it becomes more frequent until you......replace the thermostat.
    Last edited by TOK; 29 October 2014, 12:33 AM.

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  • hotshod
    replied
    Problem Solved

    The initial problem I had with my BFC Semi-Auto was that it was running cool. Over a period from 1-4hrs idling the temp at the inspection port was anything from 73*- 86*and hardly ever hitting 90 at the top of the pour and then taking 15-20min to recover. This was despite adjusting pressurestat to hit 1.5, then replacing pressurestat and running high numbers and still no joy.
    This was not how a Heat-Exchanger machine should run...!!!


    Solved .......(All temps are measured via the inspection port.)
    By removing teflon restrictor plate/washer from brew/thermosyphon line. This told me the machine was capable of running hot,very hot,so I re installed restrictor about 4 times over a period of days while testing temps, each time I increased the hole size until I achieved a near perfect result.
    Restrictor diameter was 2.2mm at the end it was 3mm.
    The machine can now idle for 1-3 hrs and temp will be 90.5* to 92*.
    A 60 ml flush will deliver 93-94* at inspection port, pressurestat is wound down to kick in at .95 and out at 1.12+ and consequently the extraction process has vastly improved.
    This result makes me very pleased even though I wasted money on a new pressurestat.

    Happy to answer an questions after a 2 month journey to my problem.

    Cheers
    Greg

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  • hotshod
    replied
    Originally posted by TOK View Post

    With regard to an effective boiler level:

    There are two probes on these models. The probe in the central position sets the LOW water level in the boiler, and the probe at the side sets the HIGH water level. I find I get good performance from my machine by positioning the probe for the HIGH water level above the nylon insulater about say 10-15 mm....
    Hi TOK

    I just thought I should point out to anyone else who is considering raising the water level within the boiler that on my particular machine the probes that set high and low levels were the opposite to what you described. With high level centrally mounted in the boiler and low level mounted beside it to the outer.

    I guess this could well be different on any make or model, so it's best to remove both probes just to be sure which one is actually the high level probe.

    Greg

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  • hotshod
    replied
    Originally posted by TOK View Post
    I find I get good performance from my machine by positioning the probe for the HIGH water level above the nylon insulator about say 10-15 mm.

    If I were checking this on my own machine, I would start by removing and cleaning the probe first to make sure it is making a good connection, and then refitting it to the position noted above.


    EDIT: I always pull the plug out of the wall before I do anything with my machine...
    Edit, re plug out of the wall .... well noted and done !!!!

    As for the water level the probe was all the way in, so I have done as you suggested removed and inspected, and it was as clean as a whistle and reset at 15mm above white nylon sleeve insulator.

    This is one aspect of the machine I have never played with, so I hope you approve of my logic as to why it may influence brew temp.
    On my last descale I checked water level via anti-vac hole.... it was 7.3cm below the top of the boiler. ( I thought that to be a lot of space for steam )

    I shall now run it for 1-2 hrs and then check results.

    BTW,... I'm fortunate to also have a VBM single boiler , while a bit tedious to use, but has been set up to run in a very narrow temp band, so it also delivers excellent extraction, and can provide a genuine comparison.

    Cheers
    Greg

    Leave a comment:


  • TOK
    replied
    Originally posted by hotshod View Post
    Thanks TOK for your lengthy and detailed response.

    Unfortunately I think you might be confusing my BFC Semi-Auto machine with the Unico Splendor though I'm sure their internals would be very similar.
    Quote.....
    "Your machine can be internally re-spec'd to run at a higher brew temperature by a knowledgeable service tech, if you wish. " end quote.
    Could you elaborate just how I could re-spec this machine to get the higher brew temp?

    I do have another quick question that may help resolve this problem.....
    This machine runs a vertical boiler. What level should the water be, when measured from the top of the boiler?
    ( I'm thinking increasing this level could add to brew temp, rightly or wrongly...!! )
    Dunno how that happened.....Must've been having a brain spasm !

    I am loathe to change a machine away from its standard spec (whatever that is) if it is working fine, and without being able to check the temp reading of this machine on a side by side test with another of known performance (or latest spec). Taking a temp reading without checking it with something else with the same instrument, at the same place in the temperature cycle, doesn't tell me much. And of course you say it was running at at a higher temperature previously, and the reason why hasn't been diagnosed. That would be the better way.

    With regard to an effective boiler level:

    There are two probes on these models. The probe in the central position sets the LOW water level in the boiler, and the probe at the side sets the HIGH water level. I find I get good performance from my machine by positioning the probe for the HIGH water level above the nylon insulater about say 10-15 mm.

    If I were checking this on my own machine, I would start by removing and cleaning the probe first to make sure it is making a good connection, and then refitting it to the position noted above.

    Then I say again, if the machine is making good coffee, put the thermocouple away....

    EDIT: I always pull the plug out of the wall before I do anything with my machine...
    Last edited by TOK; 14 October 2014, 01:38 PM.

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  • hotshod
    replied
    Thanks TOK for your lengthy and detailed response.

    Unfortunately I think you might be confusing my BFC Semi-Auto machine with the Unico Splendor though I'm sure their internals would be very similar.
    Quote.....
    "Your machine can be internally re-spec'd to run at a higher brew temperature by a knowledgeable service tech, if you wish. " end quote.
    Could you elaborate just how I could re-spec this machine to get the higher brew temp?

    I do have another quick question that may help resolve this problem.....
    This machine runs a vertical boiler. What level should the water be, when measured from the top of the boiler?
    ( I'm thinking increasing this level could add to brew temp, rightly or wrongly...!! )

    Cheers


    Greg
    Attached Files

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  • noidle22
    replied
    Are you sure your pressure gauge is accurate? If it's not reading correctly then your adjustments would not be having the changes you expect.
    Might be a silly idea but worth a try.

    Leave a comment:


  • TOK
    replied
    A philosophical discussion, because without having it on the bench in front of me, the discussion can only be based on the information you have given in this thread.

    Firstly. A great machine,. I have a Splendor Maxi (V2) on my own kitchen bench.

    If your machine was running at 93-94 degrees, then it must be assumed it is a V1 Splendor. Can you please let us have the first 4 digits of the serial number?

    The V1 Splendor has shorter steam and hot water pipes that only move in a radial direction, and with a kind of ornate pattern punched into the drip tray.

    The V2 (Maxi) Splendor has the longer ball jointed steam and hot water pipes that move in any direction and a drip tray with less ornate holes punched.

    The performance of the V2 is significantly uprated from that of the V1......stronger steam delilvery, better thermal stability.

    The V1 was an Italian spec machine and consequently ran at a higher brew temperature and required a hefty (similar to any other Italian spec machine of any brand) cooling flush.

    The V2 is thermally adjusted internally to run at a more appropriate brewing temperature for the types of beans used in the Australian market. It runs at a lower brew temperature than the V1.

    Your machine can be internally re-spec'd to run at a higher brew temperature by a knowledgeable service tech, if you wish. However that doesnt answer the question as to why you are seeing a different temperature range to previous...

    Before doing anything like that, I would first consider the sentiment expressed in post #2 above very seriously:

    "...If you were satisfied with how it made coffee before and have only become concerned because of the temperature check, then put the thermocouple away and enjoy the machine....."

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  • Dimal
    replied
    Think it's time to take your beloved machine to someone who knows them inside out mate...

    Coffee_Machinist springs to mind...

    Mal.

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  • hotshod
    replied
    No joy after a couple of weeks fiddling with this machine.

    The only way I know of to raise the brew temperature at the group head is to wind up the new pressurestat. So currently I have the pressurestat cutting in at 1.3 and out at 1.5 and this will idle at 88* and deliver about 93* at the height of the pour, .... but then take about 10min + to recover.

    SO ..... are there any tricks you can used to add extra temp, other than cranking the pressurestat...?????

    Greg

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  • hotshod
    replied
    Originally posted by Robbks View Post
    You are able to achieve the correct boiler pressure ~1.1bar (a quick search shows that's close to the factory settings)

    how long of an ON time are we talking when these temps were measured? 30-40 minutes?

    If so, then the thermosyphon system may not be operating correctly (too slow??) and not heating the group properly so you're bleeding off too much heat in the brew water.
    *Yes I can easily run at 1.1 but that does not create enough temp.

    * Time wise it seems to make no difference 1 hour warm up or continually run for 4 hrs.

    *Just not sure about thermosyphon system of a Hx machine

    As for my thermocouple I regularly calibrate to local conditions .... so I know temp showing is very accurate.

    Your thoughts greatly appreciated.

    Greg

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  • hotshod
    replied
    I have replaced the pressurestat ....... But temp is still down, not to the same degree but still low.

    To counter this I have increased pressurestat to cut in 1.1 and out at 1.3 ..... most of the time this is delivering about 89.5 to 91* measured at the inspection port after a 60min + warm up. Every now and then the group head will get quite hot with water dancing off the screen for 8-10 sec ( at these times I don't have a thermocouple in place so temp is unknown).This would happen once every 3-4 days after long idle period,2hrs+.

    So whilst machine is running better it is a mystery as to why I can't hit my old temp of 93-94*.

    Any ideas ?????

    Greg

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  • TC
    replied
    Hello Greg,

    I'm with TOK and Mal. Pressurestat.

    Re temp, if you want an accurate indication of what your machine is doing, ditch the meat thermometer and use a Scace device. We have one and can do the work/testing.
    Last edited by TC; 14 September 2014, 08:33 AM.

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