Backflushing the Rancilio Silvia

Backflushing is something to do occasional. Not everyday on a domestic espresso machine. The process is pretty generic and can be adapted to other espresso machines.


This post is about backflushing. Please note two things about that:

  1. Backflushing is only possible in a three-way valve espresso machine.
  2. Rancilio Silvia IS a three-way valve espresso machine, and can be backflushed. BUT Rancilio does NOT recommend to backflush the Rancilio Silvia. I guess the reason is, that backflushing can damage the machine, if done in the wrong way. Rancilio don’t want to extend their varanty to damage caused by improper handling of the machine. So following the advise here is on your own responsibility.

If you don’t clean, your espresso machine, you will gradual discover, that you can’t control the taste of the coffee: different coffees will taste the same, and they will all be more bitter than desired. Furthermore the espresso machines valves won’t work as precise as necessary. The coffee brewing process causes residues of coffee, oils and coffee beans to fasten on surfaces in contact with the coffee. This includes parts inside the machine, where the remains from the brewing process is sucked back when turning off the pump, when ending a brew.  There is nothing you can do to prevent that from happen.

Backflushing – step-by-step


There are a few things you need to have in place before you start a proper cleaning process.

You need the following for backflushing:

  1. A blind filter. It has the same size and form as the normal coffee filter, you use; but without holes.
  2. Espresso machine cleaning detergent. As seen below, I use Puly Cafe Polvere.


The espresso detergent is quite aggressive on oils (to attack coffee oil residues). So make sure it only is exposed to the necessary parts of the machine.

  1. Take off the cover of the drip tray, so you can see the drip tray below.
  2. Fill the blind filter with one tablespoon espresso machine cleaning detergent, or the amount recommended for the special detergent you use. 
  3. Attach the portafilter, with the blind filter and detergent, on the espresso machine, as normal.
  4. Turn on the pump, as normal, when brewing a cup of espresso coffee.
  5. You hear the pump start, and after 1 – 2 seconds it changes sound. Wait 3 – 5 seconds and turn off the pump. NOT LONGER THAN THAT!
  6. You should see excess water, with detergent shortly flush down into the drip tray through the security pipe.
  7. The excess water will be brown or black if you haven’t back flushed the machine for a long time.
  8. Wait 5 – 10 minutes for letting the detergent work inside the machine.
  9. Repeat 2 times, waiting 5 – 10 minutes in between.
  10. When you take off the portafilter, it will contain some brown water.

Portafilter wiggle

After  that, you need to clean the fitting between the portafilter and machine.

  1. Put a new spoonful of detergent in the blind filter and set the portafilter in place, but don’t fasten it in the tightest position. Hold it with your hand.
  2. Engage the pump again, as before; but wiggle the portofilter back and forward, while the water flows over the edge of the filter. Be careful if the water is hot!!! The water will splash.
  3. Stop the pump and take off the portafilter.

And now the rinsing

  1. Take the drip tray out and rinse it.
  2. Rinse the portafilter and blind filter.
  3. Attach the empty rinsed blind filter and portafilter to the machine.
  4. As before:  Engage the pump. You hear the pump start, and after 1 – 2 seconds it changes sound. Wait 3 – 5 seconds and turn off the pump.
  5. Repeat 2 times
  6. If the excess water is still dirty, do the whole back slushing process again.

That is the basic backflushing. For completing the cleaning, you also have to rinse the filter and portafilter inside:

Cleaning the portafilter and the filter

  1. Put one tablespoon espresso machine cleaning detergent in a small bowl with water. The bowl should be just big enough  to contain the portafilter and the filter. Adjust the amount of detergent according to advise given for your specific detergent.
  2. Let the portafilter and the filter stay in the water and detergent for 1 hour, or the night over.
  3. Take the portafilter and filter out, and rinse them properly with tap water.

The Rancilio Silvia as new

To be sure that every residues of detergent is gone: brew one cup of espresso with some old beans and throw it out.

If you haven’t been through this cleaning process before, you will experience that your espresso is better and less bitter.

How often?

We use the machine twice every morning for a double espresso, and 6 – 10 times every weekend. My experience is that after a month it’s time to give the Rancilio Silvia a cleaning.

Descaling the Rancilio Silvio


Descaling is an important part of the maintenance of the Rancilio Silvia.

Calcium/scale buildup  is perhaps the one thing that causes most problems on the machinery as heat valve leakage and pump failures.

Usage of a water softener filter doesn’t mean that you don’t have descale the espresso machine from time to time.

Descaling process

It is straight forward:

  1. Buy a normal descaling product for coffee machines
  2. Take the water container out of the Rancilio Silvia, clean it and fill it three quarter with warm water from the hot water tap. The warm water makes it easer for the descaling product to dissolve in the water.
  3. Put the descaling product in the water and stir
  4. If you use a water softener filter: take it off, while descaling
  5. Place the water tank in the espresso machine and lay the two water tubes in place
  6. Attach the empty portafilter to the machine
  7. Open the steamer tap
  8. Put a suitable bowl below the portafilter and the steamer tap
  9. Turn on the espresso pump by pressing the espresso button (top-left)
  10. Let the machine run until one third of the water in the water tank has run through down in the bowl. (both through the portafilter and the steamer tap).
  11. Wait 20 minutes and repeat. Let another third of the water run through
  12. Wait another 20 minutes and repeat
  13. Wait 20 minutes.

And now the cleaning up:

  1. Take out the water tank and wash it. Fill it with water and place it back in the Rancilio Silvia
  2. If you have a water softener filter: regenerate the filter and put it in place.
  3. Take off the portafilter and clean it. Place it back on the machine
  4. Put again a bowl below the portafilter and the steamer tap. Keep the steamer tap open
  5. Press the espresso button(top-left) again and let the machine pump all water in the water tank through for rinsing out any residues of the descaling product.
  6. Take off the portafilter and clean it.

Now the machine should be ready to use again. If you are afraid of any residues left: make one espresso and throw it out; and enjoy the next cup!

Water softener for the Rancilio Silvia

Recently I mounted a water softener in the Rancilio Silvia.

Calcium/scale buildup in the espresso machine is perhaps the one thing that causes most problems on the machinery as heat valve leakage and pump failures. Using a water softener also prevents going throug the descaling precedure. Depending on the quality of your tap water it might give a better tasting espresso. Even if you use a water softener, you occasional have to do a proper descaling af the machine.

How to place the water softener filter

Click on picts for larger versions.

rancilio-water-filter The water softener is a simple filter, which shall be placed in the water tank fitted to the one of the rubber tubes.
rancilio-water-filter There are two rubber tubes in the water tank. One for intake of water to the machine, and one for return water.

The intake tube is the tube with the V cuts at the end.

rancilio-water-filter-03_0 The water softener filter shall be fitted to the tube with the V cuts.
rancilio-water-filter-04_0 The filter placed in the water tank with intake end standing on the bottom of the tank. My experience is that after some time the water softener will lat down on the bottom of the tank.


Regeneration of the water softener filter

The filter works as a water softener in a dishwasher machine. From time to time you have to regenerate it with salt. It’s a quite simple operation:

  1. To regenerate the water softener filter it have to be remove from the water tank.
  2. Pour solution of 3 teaspoons of fine salt to 8oz of water through the large end of the filter so that it pours out through the small end.
  3. Allow to rest for 5 minutes then rinse out with tap water. When the water stops coming out salty, the filter has been recharged and ready to be re-installed in the Rancilio Silvia.

It shall be done regularly. How often depends on the water in your area. I do it approx once every month.

Better espresso

Apart from protecting the machine, I experienced that the espresso coffee gets a slightly smother taste. This effect will depend on the quality of the tap water.

A smother taste lets the finer nuances in the coffee beans come through.

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