Question about Bosch Thd2021gb Filtrino Fast Cup Hot Filtered Water Dispenser

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Descaling instructions bosh filtrino fast cup

Descaling instructions

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It took me ages to get his to work - seems that on the THD2023GB (Black) Filtrino, you push and hold the temp. set button for 10 seconds to get he descale programme running.

Posted on Dec 22, 2012

  • Anonymous Feb 09, 2018

    Thanks! Yes, for my black Filtrino it is the TEMP. SET button that has to be pushed and held for 10 seconds to get this to work, *not* the on/off button as the Filtrino user manual says!


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From the manual, although I cannot get it to work.

-Turn the appliance off with the on/off
-Press and hold the start/stop button.
-Turn the appliance back on with the on/
off switch.
-Release the start/stop button as soon
as the DESCALE symbol lights up.

Running the descaling programme
-Remove the water tank, pour out any
remaining water, and reinsert it.
-Prepare the descaling solution according
to the manufacturer's instructions
and pour it into the water tank up to the
calc mark. A descaling agent approved
especially for this machine is available
from Bosch Customer Service (Article
No. 310967) or from specialty retailers.
-Place a container holding at least 500 ml
under the water outlet. The container
must fit the cup stand exactly and must
remain in place. Set the cup stand to the
lowest position.
-Press and hold the start/stop button for
at least 10 seconds to start the descaling
-The descaling programme will now
run automatically. The N icon flashes
while the programme is running. (The
programme runs for approx. 10 minutes).
The descaling solution is pumped
through the appliance in multiple phases
and then runs into the container until
the water tank is almost empty. A small
amount of solution is always left in the
-When the most recently selected
temperature icon lights up, the descaling
program has finished.
-Rinse the water tank thoroughly and fill
up to the max mark with fresh water.
-Now select and draw warm water three
times to rinse out the appliance. Do not
drink this water!

Posted on Nov 03, 2012

  • Gene Haynes Nov 03, 2012

    If you can't drink the water, use white vinegar instead of the descaler. Bosch descaler:


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  • 5,353 Answers

Use white vinegar, and not CLR.
Vinegar is a food source that will not harm you, or harm kitchen drain, and also excellent descaler that will not harm metal.
You can even soak shower heads in white vinegar for several days.

Now the exact technique: I would fill affected area, and let sit for a while, pour out, then repeat with more white vinegar.

If you need further help, I’m available over the phone at

Posted on Sep 30, 2012

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