Olympia Cremina Lever Espresso Machine
 
Olympia Cremina is a hand made lever espresso machine. The first version was
the 67 model. A pressure gauge was added in 1996 and after some improvements the
Olympia Cremina 2002 model was born. The Cremina is a machine which is built to last. It is very
easy to clean and adjust, and also very easy to service. Only highly passionate
coffee lovers buy such machines as the Olympia Cremina, and that's the reason
there is a "cult" following this machine.
Although the price of a new Olympia Cremina is 2000$ plus, you can easily find a use
Cremina, at ebay or other auctions sites for less than half the price.
Buying a used Olympia Cremina
The Olympia Cremina is made of highly durable materials and that's the reason
you can expect a long life time with cautionate use and egular maintenance.
Before buying a used machine you must be absolutely sure, that the boiler is in
excellent condition, without heavy corrosion.
The pressurestat which regulates
the pressure inside the boiler must also be in excellent condition. Another
important part of this machine is the group holder assembly, which is one of the
most expensive parts of the machine. Ask the seller questions about these parts.
Does the machine work? Which is the boiler pressure when it stabilises? Is there
any corrosion? Does it leak? Does he include the single and double portafilter?
Insist on these parts, and also insist on pictures of different views of the
machine.
As a final step before you buy, check the S/H costs, as this Olympia Cremina machine
weighs approximately 10kg. If you live in Europe and you want a US 110V machine,
you will have to buy a new 220V heater element and indicator lamp, from the
Olympia Express company. If you are have trouble finding spare parts for
this machine contact Olympia express using this email olyex(AT)olympia-express.ch
Cleaning and Basic Service
Open the machine cover by unscrewing the top nut, and removing the top cover.
Inspect the boiler condition. Is the any corrosion? Is it covered with asbestos
(older 70' models)? Are the wire connections in good condition? Put the cover
back, fill with water and switch the machine on. Ensure that the group lever
faces down. Does the machine heat? Do you observe any leaks? Any hissing sounds?
If you observe leaks then rest assure you'll have some gasket replacement work
to do. If everything is OK, swith it off, open the steam valve to eliminate the
boiler pressure, and then remove the cover. If you want to do a major service
you'll have to remove the boiler cap and clean it thoroughly. This way you'll be
sure for the boiler condition, and you will also insure that the boiler water
will be clean and healthy...
If the gaskets are more than three years old, which is very likely, you will
have to replace the group gaskets with new ones. The whole procedure is
described analytically in this thread
http://www.home-barista.com/forums/viewtopic.php?t=464 in the Home-Barista
forum. Gasket replacement for used Olympia Cremina machines is highly advisable. When you
replace the gaskets don't forget to grease them with food-safe grease. New gaskets
sets can be bought by the Olympia Express company, and also by first-line dot com if
you live in the U.S.
After you have replaced any faulty gaskets and o-rings, descale the machine
thoroughly using a quality commercial descaler, following the procedures written
on the descaler package. If you are more experienced you can also use citric or
tartaric acid (50gr per lt). After descaling fill the boiler with fresh water,
switch it on,
and let it heat up again. If everything goes OK, the boiler pressure will be
approximately 1 bar, and there will be no leak. Switch it off, plug it off,
remove boiler pressure by opening the steam valve, and remove all the water
inside the boiler by turning the machine upside down on your sink (be careful!).
Clean surfaces with a moist cloth, wipe off, apply some polishing cream for
stainless steel, and polish the metal parts. Wipe with a dry cloth to improve
the final metal look. It's time to take a break, you deserve it!
Adjusting the Olympia Cremina Boiler Pressure
Inside the Olympia Cremina case there is a pressurestat. A special mechanism
which regulates the boiler pressure by activating or deactivating the boiler
heating element. The boiler water temperature is directly dependent on boiler
steam pressure so by regulating the pressure the temperature gets also
regulated. The following table shows the relevance between bar pressure and
temperature.
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There is small nut on
the pressurestat which adjusts the pressure setting. By turning it
clockwise the nut goes downwards and so the pressure setting gets
reduced. By turning it anticlockwise the setting gets increased. I've
found that boiler pressure of 0.8-0.9 bar gives the best results. The
standard setting according to the company is 0.9 bar. Turn on
the machine and wait till it stabilizes. Then open the steam valve to
eliminate false steam pressure. The boiler will activate again. Close
the steam valve and wait till it stabilizes again. When it stabilizes
notice the pressure. A pressure reading of 0.8-0.9 bar is fine. If it's
higher, for example 1.1 bar reduce the pressure setting by turning the pressurestat nut clockwise (downwards). Wait till it stabilizes. If the
new pressure reading is 1.0 then turn the nut again a bit.
Espresso Machine Boiler Pressure correlation with
Temperature
Steam
pressure |
Boiling point
|
Specific volume (steam) |
Density (steam) |
Steam
pressure |
Boiling point
|
Specific volume (steam) |
Density (steam) |
|
bar |
°C |
m3/kg |
kg/m3 |
bar |
°C |
m3/kg |
kg/m3 |
|
0 |
99.63 |
1.694 |
0.590 |
1 |
120.23 |
0.885 |
1.129 |
|
0.1 |
102.32 |
1.549 |
0.645 |
1.2 |
123.27 |
0.810 |
1.235 |
|
0.2 |
104.81 |
1.428 |
0.700 |
1.4 |
126.09 |
0.746 |
1.340 |
|
0.3 |
107.13 |
1.325 |
0.755 |
1.6 |
128.73 |
0.693 |
1.444 |
|
0.4 |
109.32 |
1.236 |
0.809 |
1.8 |
131.20 |
0.646 |
1.548 |
|
0.5 |
111.37 |
1.159 |
0.863 |
2 |
133.54 |
0.606 |
1.651 |
|
0.6 |
113.32 |
1.091 |
0.916 |
|
|
|
|
|
0.7 |
115.17 |
1.031 |
0.970 |
|
|
|
|
|
0.8 |
116.93 |
0.977 |
1.023 |
|
|
|
|
|
0.9 |
118.62 |
0.929 |
1.076 |
|
|
|
|
If you have an older 67 model then you lack the pressure (manometer)
gauge, and you can't measure the boiler pressure as easily. There are
two solutions. Either find a pressure gauge and attach it on
the machine (some technical skills are necessary), or find a cheap
digital thermometer with a K-Type probe and attach the probe on the boiler,
at the place it shows the higher reading. The boiler is made of heat conducting metal and that's
why the surface temperature is almost the same as the water temperature
inside the boiler. By measuring the boiler surface temperature you get
an indirect measurement of the water temperature inside the boiler.
Adjust the pressurestat so that the temperature gets in the 114 C
degrees range (the reading is a bit less than the actual temperature
inside the boiler).
After you've finished tweaking the pressurestat make an espresso and
taste it (use good fresh espresso coffee!). If it tastes bitter, burnt then reduce the boiler pressure. If
it is underextracted and sour then increase the boiler pressure. Bear in
mind that in order to adjust your Olympia Cremina as precisely as possible the
water level inside the boiler must be higher than 50%. Less water may
give less precise measurements and thus adjustments. |
Easy Measurement of the Espresso Brewing Temperature
There is a very easy way to measure the brewing temperature of the Olympia
Cremina. The only thing you need is a thermometer, like those used when steaming
milk. Note that this method doesn't give 100% accurate results but it gives more
than enough accuracy. It only works well for machines with high temperature
stability while brewing like the lever espresso machines (with big boilers). The
Cremina is one of those machines. Curious to find out what this method is? Look
below...
Yeah! It is as simple as this. Turn on the machine, eliminate false pressure
a couple of times by opening the steam valve, and let it stabilize. Put the
biggest cup you can find under the group. I use a Bodum cup which is made of
borosilicate glass, but you can use any glass (preferably preheated - mugs are
not ideal because they absorb a lot of the water heat). Put the thermometer in
the cup. Pull the lever up and let the hot water fill the cup. In order to do
this make sure that the boiler is full of water first! You don't want the
boiler to run out of water!
As soon as the cup/glass fills with water read the thermometer temperature.
Make sure it is in the ideal range (around 92 C degrees). If it's not then
adjust the boiler pressure again using the method described above. Don't forget
to let the machine cool down first and check if there is any pressure left,
before opening the boiler cap.
Step by Step Instructions
Olympia Cremina is quite sensitive to coffee freshness, grind setting,
tamping and dosing. You must be precise in order to get a delicious god espresso!
-
Water: 99% of your coffee is water.
Make sure you use good fresh low mineral content filtered water. Fill the
boiler to 90% level and close the boiler tap.
-
Turn on: Turn on the machine and let it
stabilize (the indicator lamp will turn off). Open the steam valve to eliminate
false steam pressure. The boiler will activate again. Close the steam valve and
let the machine stabilize again. Open the steam valve till the boiler gets
activated and close it again.
When it stabilizes again your machine will be ready to use.
-
Fresh roasted coffee. Each day that passes
after the beans are roasted is a reduction in cup quality. Use as fresh beans as
possible. If you home-roast let your beans degas for 1 to 3 days (depends on
beans origin and roast level)
-
Grind: Use a good burr grinder like a
Mazzer or a Macap, and find
the proper grind setting for the bean you are using. Finding the correct grind
setting varies
from bean to bean and upon the level of bean freshness (even air humidity
affects it!). It is also difficult to
find the correct grind if you do not have a consistent repeatable tamp and good
dosing techniques. You need to get tamp and dosing down in order to really zero
in on proper grind. Olympia Cremina is very sensitive to grind and dosing.
-
Dosing & disribution of grounds: Dosing can
have an important effect on shot quality. Try to distribute the ground coffee in
the portafilter as even as possible. Use your fingers to even the surface, tap the portafilter, use
the tamping technique you are familiar with, whatever suits you, in order to distribute EVENLY.
-
Tamping: Proper tamping pressure helps
force the hot water to evenly saturate the coffee puck before exiting out of the
spouts at the bottom of the portafilter for a good extraction. Too low a
pressure and uneven distribution increases the risk of channeling. Use a tamping pressure between
10-15kg (I have experimented with 5kg tamping with good results although even
distribution helped a lot). You can use a digital scale for practice to see how much force you use. After
tamping (use your favorite tamping style), polish the coffee puck by twisting
the tamper left and right quickly, without any pressure (polishing is not
necessary though). Make sure that the tamp
is level. Dosing, grind and distribution are much more important than tamping.
Don't try to correct a coarse grind by tamping harder.
-
Preheat shot glasses, portafilter (without
basket inside), and group by pulling two blank shots into the shot glasses. You
can also use the steam to preheat them even more.
-
 Pull:
Put the basket in the portafilter. Fit the portafilter in the group loosely, and
lift the lever up until it's parallel to the ground. Lock the portafilter in.
Lift all the way up smoothly and wait for about 7-10sec in order for the hot water
to saturate the coffee puck. Apply an even steady pull. My earliest issue using
the Olympia Cremina was under-extraction due to not pulling the lever down hard
enough. You can pull too hard also. The force is supposed to be
around 20kg. Use a scale for practice. As you pull down the lever, just pull hard enough to have two nice
continuous mouse tails dribble out like honey! Once you have achieved that just keep that same
pressure through the rest of the shot. If the shot is too fast or too slow,
over-extracted or under-extracted just change your grind on the next shot, but
follow the same procedure. Be sure that you use 7-7,5gr for a single shot
and 14-15gr for a double. Don't overfill. Anytime you pull a shot focus
on applying just enough pressure on the lever to get those nice mouse tails
regardless of shot time or pressure needed. If the shot is not good and
you use good quality fresh coffee adjust your tamping, and or dosing and pull your next shot focusing on
those nice mouse tails. For a double shot pull the lever down about 3/4 the way
on the first pull (don't let the lever resistance drop) and then smoothly pull the lever back up
(let it fill with water for a couple of seconds) and begin the second
pull. If the shot abruptly turns blond and possible starts bubbling you have a
channeling problem. If the shot gradually starts turning blond at the end of the
shot, it is probably due to coffee freshness (or coarser ground coffee than
needed). Stop the flow when the espresso gets blonde. Don't let it start
bubbling. Remove the shot glass as soon as the espresso flow gets blonde!
-
There is an alternative method of pulling the
lever up and down, until pressure build up, and then you just pull the shot.
This special method (not necessarilly better) is shown in the following video.
Olympia Cremina Espresso Extraction Video
(this is a ristretto shot which was pulled for more than 25 seconds, which is
theoretically wrong. Nevertheless the taste was fine!)
Tips
-
Water lever should be at least 75% when you
turn on the Olympia Cremina machine.
-
Open the steam valve to eliminate false steam
pressure.
-
Flush water before and after pulling shots.
-
Rinse the portafilter with a little cold water
after each use to clean it and reduce its temperature, so that you don't get
burned coffee.
-
Let your tasting buds decide what's the
optimal adjustment for your pressurestat (the factory suggests 118C-0,9bar
but that is a bit high for me)
-
If your gaskets are in good condition then
after turning off your machine the level will go up in some minutes.
-
The force on the lever while pulling should be
approximately 20kg. If you grind finer than optimal you will have to pull
harder which will cause overextracting or chanelling problems. If you grind
coarser then the result will be an under-extracted espresso. If you overfill
then pulling the lever down will be very difficult and you'll might damage
the gaskets. In this case turn off the machine, open the steam valve and
then when pressure drops remove the portafilter slowly. Don't force the
lever down!!!
-
Always use filtered water. Brita filter jugs
are one of the solutions. (I prefer the Maxtra)
-
Using a strong higher wattage boiler to fill your machine
with hot water will save you a lot of time.
-
I repeat. it's very easy to make the
mistake of overfilling the single basket. DON'T DO IT. Use 7-7,5gr of
beans. You can overfill to almost 10gr but this will only choke your
machine!!! If you use more than 20-25kg of force you're doing something
wrong!
-
Don't forget to wiggle the portafilter to
clean the group after brewing espresso. A blind filter is not necessary; you
can also use
the single basket. Lock the portafilter, raise the lever and wiggle the portafilter. Pull the lever down. Remove and clean the portafilter. Repeat
if necessary.
Maintenance and cleaning of the Olympia Cremina
To avoid the deposit of coffee grounds in the
piston: with the machine still on attach the portafilter with an empty filter
basket to the piston-head, place a large cup under the spout, pull up the
piston-lever slowly until hot water is released, holding the filter-holder at
the end of the handle and moving it to left and right slightly three or four
times. By doing this the piston, the filter and the filter-holder are rinsed.
After using the steam arm, clean it by wiping it with a damp cloth and by
turning on the steam valve for a moment.
Descaling of the Olympia Cremina boiler: Descaling the
boiler from mineral buildup is imperative. The harder the water in your area the
more frequent the need for descaling. If the water is very hard descale once a
month (using filtered water is very recommended). If it's too soft then twice per year is enough. Fill the boiler with
clean water and 50gr of anhydrous citric acid. Alternatively use a 1 to 1
solution of water to white vinegar (although a lot of rinsing will be required
with this method).
Plug into the mains. Turn on the machine and
leave it like that for one or two hours. Move the piston lever, pulling it
upwards, as when rinsing, four or five times (the liquid solution also cleans
the piston when emitted) and then turn on the steam valve. Turn off the machine,
release the steam from the boiler, unscrew the cap of the boiler and empty the
boiler. Repeat the same procedure with clean water. To be safe repeat the
procedure with clean water once more. If the machine is not used for some time,
empty the boiler completely and rinse it out with fresh water when the machine
is put back into use. Do not turn on the machine if the water-level indicator is
at the lower level or before the boiler is filled with water. In this way the
heating element is not damaged. The Olympia Cremina is protected by a thermostat
against overheating and overpressure.
Final Words
Your Olympia Cremina machine is a fabulous machine built to last and serve
you for may years. Take care of it, and it will take care of your coffee needs
for may years...
IMPORTANT RESOURCE:
If you want to learn more about espresso and how to make a perfect
shot
click here for the advanced
espresso guide!
OR RETURN TO THE
MAIN MENU
(Additional Sources of Information:
www.home-barista.com )
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