Single boiler
One boiler handles brew water and steam at different temperature ranges. This can keep a machine compact and affordable, but switching between brewing and steaming takes more time and attention.
Heat exchanger
A heat exchanger lets the machine support brewing and steaming through one main boiler system. The exact temperature strategy varies by machine. Lelit's MaraX uses a dual probe HX system and guided temperature settings.
Dual boiler
Separate boilers handle coffee and steam. That gives each job its own thermal system and is especially useful when you make several milk drinks or want more direct control over brew temperature.
How this maps to Lelit
Anna and Victoria sit in the single boiler side of the range. MaraX is the heat exchanger choice in our core comparison set. Elizabeth and Bianca are dual boiler machines. That makes boiler design a useful first filter before you compare smaller features.
Product specifications and reference pricing in this page set were checked against Lelit manufacturer materials during preparation. Prices and availability can change.