Common Nanopresso Brewing Mistakes and How to Fix Them
Jan 11, 2022Daniel Kennedy

Common Nanopresso Brewing Mistakes and How to Fix Them

By: Travel and Adventure writer Breanna Wilson

Several factors affect the Nanopresso’s espresso extraction process, from water temperature to grind size. Learn which mistakes are the most common – and how to fix them.

Wacaco has done everything they could to make brewing – whether it’s espresso or coffee – as easy as it gets. One look at the NanopressoMinipressoPicopressoCuppamoka, and Pipamoka, and that’s clear.

But as is the case with all brewing processes, there will be mistakes. It’s inevitable. Especially when you’re brewing on the go, factors such as not achieving the perfect water temperature, or using too few grinds, are sometimes out of your control. It’s the price to pay for backcountry and road trip brewing.

But it doesn’t have to be. And, as you start to use your hand-powered brewer more and more, and the more you know about recognizing potential issues from the start, the better your resulting brews will be. Consistent brewing means consistent café-quality taste anywhere, from the backcountry to the top of a mountain.

With factors from your grind size not being dialed in to your water temperature being too low or too high, these are the most common brewing mistakes made when brewing with the Nanopresso and how to fix them. Let’s get into it.

Learn about these common Nanopresso brewing mistakes and how to fix them:

- Wrong grind size
- Wrong Water Temperature
- How to Properly Clean Your Nanopresso
- Help! My Espresso Isn’t Coming Out in a Stream

Wrong Grind Size: How To Dial In Your Grind For Your Nanopresso.

For the Nanopresso, the ideal grind size is a small fine grind. Look for a size similar to table salt but slightly more refined. Once your grounds are ready, weigh out 8 grams for brewing with your Nanopresso.

While buying your grounds pre-ground means you’ve already achieved this perfectly fine grind, it is something we never recommend. As the espresso connoisseur you’re on your way to being, we recommend grinding your coffee beans fresh for a few reasons.

First, grinding fresh releases aromas that will come through in your brew. The less fresh your grounds are, the less aroma there is, and I think we can all agree that smelling your brew is almost as satisfying as tasting it.

Second, grinding your grounds means you have more control over the size, which is extremely important as you’ll be able to tell.

If your grind is too coarse, your Nanopresso hand-held brewer won’t build up pressure correctly, and the result will be a poor, watery extraction without crema. This under-extracted cup will leave you with notes of sourness and acidity that are just plain unpleasant.

If your grind is too fine, it will be hard to pump your Nanopresso and extract your espresso. You should aim for smooth, even pumps at a rate of one pump per second. If that is too difficult, your grind is too fine. If your grind is too fine, you’ll be left with an over-extracted espresso, leaving you an overpowering and unpleasant shot with notes of bitterness. (Again, not pleasant.)

So, how do you know you have the right grind? Well, as we mentioned above, during the extraction process, you’ll know when the pumping process is easy. You will feel the pressure build during the extraction, but it will not be overly daunting or too hard to extract. The flow should be free and steady and be golden brown. Once you taste your pulled shot, note the flavor profile, and as long as it tastes balanced and doesn’t have too many of the unpleasant notes above, you’ve achieved the correct grind size.

Wrong Water Temperature: What To Do When Your Brewing Temperature Is Incorrect. 

Next, let’s talk about getting consistently great crema with your Nanopresso and brewing with the correct water temperature.

This video on the secrets to great crema is a great resource.

Pre-heating your Nanopresso helps warm the body of the brewer up so that your extraction is clean and smooth. When it’s time for the extraction, the ideal water temperature should be close to boiling, or about 195°F.

If you brew with water between the 195°F to 205°F range, this is the ideal temperature for water-soluble flavor compounds to most easily dissolve in water.

Water above this temperature means you over dissolve these flavor compounds (unbalanced). Water below this temperature means they won’t dissolve as easily (weak). And, when you put it like that, it’s clear to see that paying attention to your water temperature might be one of the most overlooked factors in proper brewing.

If you’re serious about your brewing, it’s time to invest in a decent thermometer so you can adequately measure your water temperature. This is also where pre-heating your Nanopresso comes in – it helps your brewer maintain this temperature throughout the extraction.

How to Properly Clean Your Nanopresso

There are a few simple steps to follow to clean your Nanopresso properly. By following these steps, you avoid common issues such as mineral build up, clogging from loose grounds, and more. 

The three most common issues that are related to improper cleaning are:

1. Your Nanopresso isn’t pressurizing* the way it used to. How do you know your Nanopresso isn’t pressurizing correctly? It will take more than the usual amount of pumps (6 – 8) to build pressure, or it won’t build any pressure at all. 
2. Your pull isn’t coming out in an even stream.
3. Your puck isn’t evenly saturated, and your extraction is uneven.
(*If you want to use your Nanopresso in non-pressurized mode, so that it functions more like a traditional tabletop espresso machine, here’s how to do that.)

To properly clean your Nanopresso after using:

  1. The first step is to always enjoy your espresso while it’s hot.
  2. Once you’ve enjoyed your single shot, it’s time to remove your puck and examine if your extraction was done correctly. To do this, with a firm, even whack, tap the coffee filter basket (exposed grounds side down) on an even surface. After doing this, the puck should become flush with the top of the coffee filter basket. This means it’s loose and ready to come out evenly. Holding the coffee filter basket with the loosened grounds in your right hand, extend your left arm in front of you. Using your left arm as a brace, and holding the coffee filter basket ground side down, tap your right wrist against your left forearm to release the puck in one easy and firm movement. If your grounds were the right size and your extraction was done correctly, this should happen easily. If not, or if your puck is not wet throughout (meaning water was evenly disbursed through the grounds), that’s an indicator that you made a mistake during the extraction process.

 Now that you’ve determined whether your espresso was extracted correctly through a taste and puck test, it’s time to give it a deep clean. To thoroughly clean your Nanopresso, do the following.

  1. Continue to disassemble your Nanopresso. Twist off the water tank and set it to the side with the portafilter head. Leave the pump in the extended pumping position.
  2. Rinse the water tank with hot water and a cloth. Set aside to dry.
  3. Remove the metal nozzle from inside the portafilter head.
  4. Rinse the outer part of the head with hot water and a cloth. Set aside to dry. 
  5. Once a month, or every 30 extractions or so, it’s recommended that you remove the rubber piece around the metal nozzle. This is extremely important because this piece creates the vacuum seal necessary to create the right amount of pressure for a great extraction.
  6. Remove any grounds that may have accumulated here using your brush and wipe both pieces with a hot damp cloth. Set both pieces aside to dry.

For an extra deep clean – and once every six months to one year – we recommend cleaning the metal mesh. To do this:

  1. To clean under the metal mesh, use an Allen Wrench to unscrew the 3 screws, and run the metal filter under running water for a few seconds. Allow to dry and then put back together. 

Now, if you’re finding your Nanopresso isn’t pressurizing like it used to, this step is very important in the cleaning process.

  1. On the inside of the Nanopresso body, where the portafilter sits, there is an orange rubber gasket. Remove this from the body. Give it a rinse under hot water, using the brush if you need to dislodge any stuck grounds. Using one finger, snap the gasket back into place.
  2. To repressurize your Nanopresso, you will need to run hot water through it. To do that, add hot water to the water tank and attach it onto the body of your Nanopresso. Do not attach the portafilter or head to the Nanopresso. Instead, turn your Nanopresso over and start pumping to run the hot water through the gasket. Do this over a wide mouth mug or bowl to catch the hot water.

To continue cleaning your Nanopresso, follow these steps:

  1. Using a hot damp cloth wipe the inside of the Nanopresso body to remove all coffee grounds and espresso remnants.
  2. Allow each piece to dry separately. 
  3. Wash the coffee filter basket with warm water, making sure to remove all coffee grounds.
  4. Once all the Nanopresso’s pieces are dry, put your Nanopresso back together and place it back in the protective case for your next use.

This video is a great resource on how to properly clean and maintain your Nanopresso for even faster maintenance between uses. Bookmark this page and save this YouTube video for quick access when your Nanopresso is in need of a deep clean.

 Help! My Espresso Isn’t Coming Out in a Stream

 If your Nanopresso isn’t extracting in a beautiful, singular stream through the portafilter nozzle, there may be a few things wrong. This could range from the portafilter head not being screwed on tight enough to the wrong number of grounds in the coffee basket.

If the portafilter head is not screwed on tightly enough, there will be spaces and air where you don’t want them, allowing the extracted espresso to seep into places it’s not intended to. If it is screwed on tightly, and you’re still having this issue, remeasure the number of grounds you’re using in your coffee filter basket – you may have overweighed your grounds. (Remember: 8 grams of fine grounds is your ideal amount.)

If you have the wrong number of grounds in the coffee basket, the portafilter’s nozzle (the metal part) will not perfectly fit into the coffee basket. You’ll be able to tell if this is/will be an issue when you tamp your grounds. If you don’t have at least a few millimeters of space for the metal nozzle to fit snuggly intact with the grounds, you are going to have an issue.

If you didn’t put the gasket in correctly or repressurize it after cleaning, this could cause another issue with the stream and the Nanopresso not reaching the right amount of pressure when pumping. This should be the first thing you check when encountering any pressurization issue.

Still have questions or problems brewing with your Nanopresso? Join our Wacaco Facebook group and let us know there.

Jan 11, 2022 Daniel Kennedy