How to re-start your professional coffee maker safely after a long period of inactivity

How to re-start your professional coffee maker safely after a long period of inactivity

May 26, 2020

This current pandemic has forced a great majority of owners to close their businesses for a prolonged period of time. But over the past few weeks, businesses have slowly been resuming their operations. As a restaurant or café owner, is there an impact on your espresso machine’s mechanics and efficiency if it has been idle for a lengthy period of time?

Underneath a professional espresso machine

You first have to understand the mechanics of an espresso machine to clearly identify the sources of possible "problems" caused by its inactivity, says Pier-Paul Fortin of l’Atelier Espresso. Most commercial espresso machines operate with a heat exchanger system. This means that inside the machine there is a boiler (kettle). The function of this boiler is to maintain the water at a determined temperature and pressure in order to be able to supply steam almost continuously. Inside this boiler, there is a closed flue running through it. This duct is of a specific length and diameter to enable heat transfer from the boiler to the water inside the circuit. This is called the heat exchanger. This makes it possible to continuously supply heated water at a controlled temperature, almost infinitely.

Once we understand these principles, we can begin to identify the sources of problems caused by keeping the machine inactive for a long time. Each extraction leaves its share of oils and particles that stick to the filter, nozzle head and seals, and this residue is sometimes absorbed into the conduits. In addition to jeopardizing your machine’s proper functioning, poor maintenance can cause excess bitterness during extractions and a more rancid taste.

Don't worry about the boiler

Although the water will be stagnant in this part of the machine, it has been heated and pressurized above the boiling temperature. When restarting the machine it will do so again. The water was therefore previously pasteurized and will become so again, fairly quickly. A few seconds or even minutes are long enough to pasteurize the water at this temperature, says Pier-Paul.

The heat exchanger

Since this component holds a small amount of water, all you need to do is "purge" the water remaining in this part. To do so, just run water by activating the machine as if you wanted to make a coffee, so that the water flows from the group head.

Water filtration

The main source of problems will involve the water filtration system. The filter’s job is to create a barrier to impurities in order to provide better water quality. Impurities therefore accumulate in it day after day. The standing water inside is a fertile playground for bacteria, the accumulation of impurities, and it also decreases filtration efficiency (overload).

Solution: Since there are several different water filtration systems, you should know about yours and be sure to clean/replace the filtration media accordingly. It is essential to change it or have it changed before you restart your espresso machine to avoid ending up with lime build-up.

The mechanics of the commercial espresso machine

The sudden closure of restaurants, cafes and other businesses likely did not allow adequate time to clean the equipment properly. The machine itself is not at risk if your equipment has been kept in a heated room; if not, always have your equipment checked by a professional. On the other hand, the machine’s interior may need a little love after a long vacation. So here’s what to do to descale your professional espresso machine’s brew group and flow valve.


The group head

The backflush: A simple operation used to clean the ducts, i.e. the group depressurization valve. It is an outlet pipe for excess pressure, which enables you to clean the extraction system with a powerful water jet. 
  1. Place the blind filter (the one without the hole) into the filter holder. Put 5 grams of Puly Caff Verde detergent into the blind filter and place the filter holder into the machine group, activate the machine for 5-10 seconds and stop it. Wait 10 seconds.
  2. Repeat 4 machine activation cycles for 5-10 seconds with a 10-second pause between.
  3. Remove the filter holder, remove the blind filter and replace the regular filter.
  4. Run water through the group without the filter holder for 10 seconds.

This operation does 2 things:
  • It cleans the part of the pipes from which the water exits to make coffee.
  • It cleans the depressurization valve to prevent it from sticking and remaining in the open position, which will require a repair technician if so.

Should the filter holder be soaked in a solution?

The filter holder must absolutely be clean and contain no residue from the last extraction.

“Would you fry your eggs in the same dirty pan as the day before without washing it? NO. The same goes for the filter holder, otherwise your coffee will taste the one brewed before”, says Pier-Paul.

Immerse the filters and filter holders for 15 minutes into a solution containing 1 liter of very hot water mixed with 10g of Puly powder. Then rinse them with water.



Buy Puly Caff Verde

Milk pipe cleaning

In addition to cleaning the frother and milk jug on a daily basis, it is important to thoroughly clean the frother's drip drain. This step does not only clean it, but it improves deodorization and ensures the nozzle’s proper operation, eliminating any organic residue capable of causing malfunction, mould or unpleasant odours.

Frequency of use

Use Puly Milk liquid to clean the steam nozzle and the milk tube approximately every 50 uses and whenever you need to return the machine to good working order, as in this case, after a long period of inactivity.

  1. Add 25 ml of Puly Milk to 500 ml of cold water: the blue section on the left is designed so that you can squeeze the bottle until the required amount enters the measuring container (0-30 ml) before opening and pouring.
  2. Insert the steam nozzle into the solution.
  3. Open and shut off the steam 7 to 10 times, which will cause suction.
  4. Open and shut off the steamer 3 times in cold clean water to ensure it is properly rinsed.

Buy Puly Milk

The grinder

Coffee contains oils that settle and accumulate in several places in the grinder. Over time, it will go rancid. It is therefore a good time to take advantage of the break to clean the grinders and remove oily deposits, mould or accumulation.
Empty the coffee bean container and pour in a package of Puly Grind Verde crystals.

  1. Grind the contents of the package with coffee beans.
  2. Once everything is ground, add coffee beans and discard the first two grinds.

Puly Grind easily cleans up oils or residues trapped between the grinder blades and prevents you from dismantling the grinders each time you clean them.

Buy Puly Grinder Cleaner

Cleaning frequency

As Pier-Paul Fortin, owner of l’Atelier Espresso explains, cleaning frequency is a polarizing topic within the industry. There are therefore as many recommendations as there are technicians. Here are his recommendations for all commercial machines in restaurants, cafes and others:


Commercial machines

Backflush EVERY day!!!! Do so before your establishment’s closing or during a period of low traffic. The amount of coffee made per day has less of an impact than the duration of downtime between each coffee made. It is during these periods that coffee residues can solidify and eventually create an obstruction.

Residential machines

Once a week and again, the number of coffees made per day doesn't matter. You must further adapt your cleaning behaviour based on the time during which your machine remains on without making coffee.

Here is a reminder of the daily cleaning tasks for your espresso machine:

  1. Change the water filter
  2. Clean the group head
  3. Soak the filter holder
  4. Descale the milk pipes and the frother's drip drain
  5. Remove greasy deposits from the grinder

Have a great reopening!