système de chaudière unique

CONT: In a single boiler system, once an espresso is extracted, the boiler can take almost a full minute to heat up to the point where steam can be produced for frothing milk, and then requires a ""cool down"" time before another espresso can be brewed. … Double boiler systems bypass the delays caused by single boiler systems entirely by having one boiler specifically for steam, and one designated for espresso extraction.