Who invented the E61 group?
The E61 was invented by Ernesto Valente and he christened the group 'E' which is short for eclipse as there was a solar eclipse in 1961. The Faema E61 espresso coffee group was the first heat exchanger machine, meaning that fresh water was used for making espresso instead of boiled water.
How do you maintain the E61 group?
Maintaining the E61 group is easy to do, every so often the E61 lever needs to be lubricated with food-safe Molykote 111 grease 6g. The brass parts have a lifespan and will need to be replaced over time. The mushroom can become corroded and caked with minerals, the E61Rocket E61 Group Mushroom Gicleur is best replaced along with the mushroom.
The E61 group can be upgraded with silicon group gaskets, which are easier to remove and install than the standard rubber baskets. Installing IMS E&B competition E61 shower screens can help with dryer pucks and less channeling while installing an Orman E61 Group Pressure Gauge is an inexpensive tool to show extraction pressure.
PVC parts can be retrofitted with Italian walnut portafilter handles, steam taps, and lever handles, which look great against chrome and stainless steel machines.
What is the difference between an E61 group and a lever group?
An E61 group is connected to the boiler with a thermosyphon loop and can take 20/30 min to warm up, even with a few pulls of water to warm the group. This is due to the sheer volume of brass in the group. This mass is what keeps the temperature stable in the group.
Spring Lever machines have the groups bolted to the boilers and warmup time is less at in 15 to 30 minutes. Typically the group needs a good flush through. When you pull the lever for the spring group head, you are compressing the spring piston in the group head, creating pressure. As you release the lever, the spring slowly decompresses as it brews your espresso. Spring lever delivers beautiful espresso as it pulls a direct 9 bar and gradually decreases over time ( pressure profiling), while the E61 gives you full control of the pressure during the brew.
In both the E61 and spring lever piston groups - hot water meets the coffee at lower pressure for pre-infusion, for coffee puck saturation, then the brew pressure increases to start, before gradually decreasing over the shot extraction. Prefusion ensures that all of the puck is extracted.