Semiautomatic Machines

Pump-driven

A refinement of the piston machine is the pump-driven machine, which was introduced in the Faema E61 in 1961. Instead of using manual force, a motor-driven pump provides the force necessary for espresso brewing. Commercial or some high-end home machines are often attached directly to the plumbing of the site; lower-end home machines have built-in water reservoirs.Four variants exist in home machines, depending on how brew water and steam are boiled; in discussion these are generally known by acronyms.

Single Boiler (SB)

Single Boiler, Dual Use (SB/DU)

Heat Exchanger (HX)

Dual Boiler (DB)