How flow-through espresso heaters work
How flow-through espresso heaters work
Thermoblock Notes explains the heater inside many home espresso machines. It covers how a thermoblock differs from a boiler, how it warms up, and how it handles brewing and steam. Every page points you back to your own manual for the details of your model.
Written for home owners and hobbyists who have a thermoblock machine, or are thinking about one.
All the notes
- What Is a Thermoblock in an Espresso Machine?
A thermoblock is a flow-through heater. See what's inside it, what it does in your machine, and where to check which heater your model has.
- Thermoblock vs Boiler: How the Heating Differs
A boiler keeps a tank of hot water ready. A thermoblock heats water as it flows. See how each approach changes warm-up, steam and temperature.
- How a Thermoblock Heats Water as It Flows
Follow the water from the tank to the cup. See what the pump, the tube and the heated block each do, and why flow speed changes the result.
- Why Thermoblock Machines Warm Up Quickly
One maker's manual gives a heat-up time of under a minute, and thermoblocks are described as having a relatively short heat-up time.
- Temperature Stability in Thermoblock Machines
Why brew temperature can drift during a shot on a thermoblock machine, and what affects it.
- Switching From Brewing to Steam on a Thermoblock Machine
Why some machines pause or cool down between coffee and steam, how thermoblock steam works, and where to find your model's own wait times.