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Thread: Silvia Water Temperature - advice needed

  1. #1
    Member SamR's Avatar
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    Silvia Water Temperature - advice needed

    Gene Cafe Coffee Roaster $850 - Free Beans Free Freight
    Ive found recently that a shot can be drunk immediately after pouring and is only warm - not as hot as I remember it being. So I tested the water temperature today with a thermometer ....I first dispensed water from the group directly into a cup and placed the thermometer in so as to warm the cup through and to get the reading on the thermometer up so it didnt have as far to sweep around the dial as the water cooled. I then dispensed the water and did the actual test with the cup already warm and the thermometer reading higher - the temperature didnt go any higher than 80 degrees. I repeated the test several times, even using the milk jug, to allow for any thermal differences between metal and ceramic. The reading still wouldnt go past 80 degrees. I also tried the hot water from the wand and it reached a little under 80 degrees.

    I was under the impression that the water temperature should be about 90-92 degrees. Is this right? If so, any suggestions on what might be wrong and how it can be remedied?

    Appreciate any advice.

  2. #2
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    Re: Silvia Water Temperature - advice needed

    Hi SamR,

    The water in the cup will be cooler than at the group head due to cooling as it drops through the air into the cup. That will account for some of it.

    You should notice the water temperature go up a bit just as the boiler element turns off though (and the boiler is at the top of its swing).

    charlie

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    Re: Silvia Water Temperature - advice needed

    Hi SamR, i had a bit of a play with my thermometer the other day, on my 1grp commercial Brugnetti i was getting 86 from the ghead, i am able to run a lot more water than you but as its a commercial machine. used the same method as you

    but i get 93ish from hot water, but again its a HX machine with a 7l boiler

    by "repeating" a few times did you do it at different parts of the cycle?
    eg light just on, light just off etc

    cant offer any help in adjusting your Silvia but



  4. #4
    Member SamR's Avatar
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    Re: Silvia Water Temperature - advice needed

    Thanks - yes I tried it at different points of the cycle. Even without a thermometer reading I know, just from a "seat of the pants" perspective, that its running cooler. I wonder if the thermostats just need replacing?

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    Re: Silvia Water Temperature - advice needed

    Hi SamR,

    Yep - 92 deg is the oft quoted ideal temperature for the water as it hits the coffee.

    Firstly - one of the best things Ive done to my Silvia is the gronk - you get so much more info on what the temperature is doing.

    Id also check your thermometer for accuracy before going too far (in boiling water / ice).

    As Charlie mentioned, the measurement of water temperature in cups etc has been notoriously inaccurate - the traditional best compromise was to use a cut-down styrofoam style disposable cup with the thermometer punched through the side (so a low volume and fits the group seal).

    A much better way would be a thermocouple under the water distrubutor or shower screen.

    You were worried about the reaction time of the thermometer - in free flow the pump pushes ~90ml in 10 seconds, ie. nearly a third of the boiler, which will drop the temp quickly which doesnt give you much time to get an accurate temp. *The bottom of the cycle on my Silvia is 90 deg per gronk - run water at that point and its downhill double-plus quick.

  6. #6
    Mal Dimal's Avatar
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    Re: Silvia Water Temperature - advice needed

    The only accurate method to use for this, is via a Scace Device at the premises of one of our many site sponsors who have them.

    Alternatively, you can prepare a shot in the normal way, and just prior to locking the Group Handle(GH) in place, site the tip of a bead t/couple at about half radius on top of the puck and then lock in. The key thing to remember with Dual Purpose Single Boiler machines, they are designed to deliver brew water at the nominal flow rate of 120ml/Minute maximum when pulling a double espresso.

    Allowing water to free-flow without resistance significantly upsets the capability of the machine to deliver water within the ideal range of temperature.

    That is why the Scace Device is designed the way it is, to try and replicate exactly what is occurring when you pull a shot. Without access to a Scace Device, your only option is to actually pull a shot with a t/couple bead in place as described. Using any other method just doesnt mean much at all Im afraid.... :-?

    Mal.

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    Re: Silvia Water Temperature - advice needed

    My understanding is that the Scace or "thermocouple on a puck" is needed to look at the temp profile during a shot - SamRs problem sounded a little less subtle?

    Just testing a cup vs shower screen (with a thermocouple)...
    - From top of cycle: 85 in cup vs ~100 deg held for 5 sec (then falling at 1 deg/sec)
    - From bottom of cycle: 77 in cup vs ~90 deg held for for 4 sec then same fall off.

    So your 80 in a cup sounds ballparkishly OK ???

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    Mal Dimal's Avatar
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    Re: Silvia Water Temperature - advice needed

    Quote Originally Posted by 4B66626E630F0 link=1252543620/5#5 date=1252572151
    The only accurate method to use for this, is via a Scace Device at the premises of one of our many site sponsors who have them.
    Quote Originally Posted by 7C6C6E7D6A760F0 link=1252543620/6#6 date=1252588310
    So your 80 in a cup sounds ballparkishly OK ???
    Hence my use of the word "accurate" above..... ;)

    What ever temperature the water is at once it leaves the Group has no bearing whatsoever on whether this equates to the water being within the ideal temperature range when it hits the top of the puck. All other methods are just guesswork.... :-?

    Mal.



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