Steam Arm Blocking
Skipping or missing the wipe and steam purge before and after using the steam arm can cause the pinholes at the end of the steam tube to block with coagulated milk. More importantly, however, this coagulation will also jam the small springs and valves located at the top of the steam arm and stop their functionality. If the steam wand does become coated in milk you should never submerge the steam wand in liquid for a long length of time. This causes a condition called ‘Sour Boiler’ and is expensive to correct.
Group Head Not Dispensing
Group head cleaning should be done regularly to prevent the build-up of deposits that can produce a rancid taste in the coffee. It can also block off the perforations in the shower head filter that are essential for the proper operation of the machine.
Cleaning after each kilo of coffee is a reasonable frequency guide. However, carefully following the instructions printed on the tub of the cleaner should also be strictly observed for your safety (We use Puly Brand). For instance, any overdosing of cleaning powder can cause a hazardous build-up of pressure in the group head, so it is important not to exceed the recommended dose.
Secondly, after the initial treatment of five flushing cycles with the cleaning powder, the subsequent rinsing cycles must be carried out in full. Failure to do so can leave deposits of cleaner that then dry and encrust the valves, and small springs inside the regulating mechanisms of the machine thus preventing their reliable operation.
Our final recommendation is that the whole operation is always carried out at the start, rather than the end of a shift. It helps to prevent crusting.
Group Basket Leaking
Prevention is a simple operation that is carried out immediately after charging the group basket with a fresh portion of ground coffee and where excess grains spill onto the rim of the basket. Always remove these with a brief wipe with the palm of your hand – sometimes described as “Blessing the Coffee.” Failure to do this creates a build-up of coffee particles on the rubber of the group head seal that that affects the seal’s ability to do its job.
Water leeching onto a worktop is often assumed to be a leak from the machine. However, a blockage on the drain more often than not is the cause. The source of the leak can be quickly checked by removing the drip tray grill and cover and examining the small funnel underneath.
Gently pour water into it and determine that it readily flows away, if not then the attached drain tube could be blocked or just lying at the wrong angle to allow the liquid to flow away in which case it will either need to be cleaned or re-adjusted to ensure a downward flow.
A shot of espresso is only 30ml, and the small volume can become cool unless care is taken to keep it warm. One precaution is always to keep the group handle lodged in the hot group head and secondly to store porcelain cups “base down” on the machine’s cup warmer. The objective is to maintain the heat in the coffee that, of course, sits in the bottom of the cup.