| Olympia Cremina Lever Espresso Machine |
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The Ultimate Guide from FreshCoffeeShop with video showing how to make espresso properly |
| Steam pressure
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Boiling point | Specific volume (steam) | Density (steam) | Steam pressure
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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!
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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.
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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.
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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)
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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.
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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.
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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.
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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.
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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.
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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!
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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
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Water lever should be at least 75% when you turn on the Olympia Cremina machine.
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Open the steam valve to eliminate false steam pressure.
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Flush water before and after pulling shots.
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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.
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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)
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If your gaskets are in good condition then after turning off your machine the level will go up in some minutes.
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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!!!
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Always use filtered water. Brita filter jugs are one of the solutions. (I prefer the Maxtra)
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Using a strong higher wattage boiler to fill your machine with hot water will save you a lot of time.
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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!
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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...
You can also download this article as a pdf file by clicking this link: Download Olympia Cremina PDF
IMPORTANT RESOURCE:
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(Additional Sources of Information: www.home-barista.com )







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.