Level 3 Barista - Preparing your espresso machine for service

Preparing Your Espresso Machine for Service

Before extracting espresso, you need to check that the espresso machine is clean and working properly. The main steps are listed below.

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Step 1 – Clean and dry portafilters

Clean and dry portafilters. See text below.

Step 2 – Flush group head

Flush group head. See text below.

Step 3 – Check pressures

The pressure gauge measures the pressure at the group head and at the boiler.

The group head pressure needs to be around nine bars to make sure there is enough pressure to force the water through the coffee grinds and extract a good crema on the espresso.
The steam boiler pressure is normally around one bar when the steam control isn’t in use.

Step 4 – Check temperature

The temperature gauge shows the temperature of the water at the group head. This temperature should be between 85° and 95°C and is normally centred on 90°C.

Step 5 – Check water level

Your machine may have a water level indicator that shows the water level inside the boiler. Normally this is regulated automatically and the level should always remain between the ‘min and max’ (short for minimum and maximum) indicators. Some machines have a manual override that allows you to draw more water into the boiler if necessary. Water levels are usually set at just over half full to allow steam to form in the boiler.

Step 6 – Flush or purge wand before heating milk

Flush or purge wand before heating milk. See text below.

Cleaning group heads, portafilter and steam wand

Cleaning the espresso machine should be done at the end of service in preparation for the next shift or day. Some cleaning also needs to be carried out during service.

Regular cleaning is important to make sure the machine continues to work properly and produce quality espresso beverages. Oils from coffee can coat machine surfaces and, if left on, they can taint the fresh coffee being produced.

Flushing and cleaning dispersion screens and head seals

Flush the group heads before service and as often as possible during service. This helps to keep the head seals and dispersion screens clean and clear of used ground coffee and any other debris. Dispersion screens are also known as showers or simply screens.

To flush a group head, run it without a portafilter locked. This purges any debris. Use a stiff plastic brush to clean out any coffee grinds and debris around the head seal.

Head seals and dispersion screens should also be cleaned and checked at the end of service in preparation for the next shift.

Detach the dispersion screen by undoing the short screw that holds it into the group head. Make sure that the drip tray is still in place to avoid losing the screw if you drop it. The screw is quite small so can be lost easily if dropped.

Soak the dispersion screen in cleaning solution with the portafilter. Then wash, rinse thoroughly, and replace it straight away.

Rinse the head seal and check for any deterioration. If it has become brittle, then replace it with a new seal.

Back flushing

Back flushing keeps debris from building up in the machine. Back flush at the end of service and whenever there is a break in service during the day.

To back flush during service, you need to insert a blind into the portafilter and lock it into place. Next, run the group heads for 5–10 seconds, then turn it off. You will hear and see a surge of water spill into the drain tray. Do this 4–6 times until the water in the blind filter is clear of any debris.

At the end of the shift, use the same process but add cleaning powder into the blind. Cleaning powder contains caustic soda which dissolves the oils and residue coating the machine. This substance is very toxic and you must back flush the machine thoroughly with hot water before using it again.

Important Note - Caution!

Cleaning powders are very corrosive!

- Read all instructions carefully.
- Wear rubber gloves.
- Clean up any spills immediately with fresh water or as instructed.

Cleaning portafilters

If not cleaned regularly, the portafilter’s metal parts can become coated and stained with coffee oils, this can affect coffee flavour and crema.

Remove the filter basket from the portafilter. Soak the metal parts of the portafilter and the filter basket in a container of water that has had cleaning agent dissolved into it. Take care not to soak the plastic parts of the portafilter handles. Check the cleaning agent instructions for how long you need to soak the parts.

Wearing gloves, scrub off any coffee residue, then wash the filter baskets and portafilter in warm soapy water and rinse thoroughly.

Put the filter basket and portafilter back together and lock it back into place in the group head.

Cleaning the steam wand

During service, the steam wand should be wiped immediately after use to avoid the milk baking onto it. Milk can also get sucked into the wand during the aerating process so, before use, purge the steam wand by opening it fully for 2–3 seconds to flush out any left over milk.

Make sure the steam wand is thoroughly cleaned at the end of service ready for the next day or shift. If it has milk residue on it, wrap a wet cloth around the wand and open the steam valve a small amount for a minute or so. This softens the residue so it can be easily wiped off. This is a more hygienic and efficient method than soaking in water. Do not use rough scrubbers to clean the steam wand as it can remove the coating and make it harder to clean in future.

When you have finished cleaning the wand push it back in toward the drip tray so it is out of the way.

Activity 1: Prepare your espresso machine for service

1. Talk to your teacher/tutor about the steps you need to follow to prepare your espresso machine.