Diagnosis
Your De'Longhi Magnifica S is producing lukewarm coffee primarily due to heat loss. The machine's internal brew group (infuser) and the ceramic cups cool down between uses, stealing heat from the freshly brewed espresso. Additionally, the brew temperature may be set too low in the machine's menu.
How to Fix It
First, actively pre-heat the system. Press the rinse/cleaning button to run hot water through the brew circuit and warm the infuser. Always pre-heat your cups using the machine's hot water dispenser (press the steam/hot water button briefly over the cup). Next, verify and increase the brew temperature setting:
- Ensure the machine is in standby (coffee cup icon illuminated on the dial).
- Turn the selection dial to the coffee cup icon.
- Press and hold the 1-cup button for about 5 seconds until the three temperature lights start flashing.
- Press the 1-cup button to cycle through Low, Medium, and High temperature settings. Select High for the hottest coffee.
- Press the 2-cup button to confirm and save the setting.
If That Didn't Work
If coffee remains lukewarm after these steps, perform a descaling cycle. Mineral scale buildup inside the thermoblock heater can drastically reduce heating efficiency. Also, check that the machine's water tank is not overfilled with cold water, which can lower the system's starting temperature. Ensure the machine has had adequate time to fully heat up from a cold start (typically 2-3 minutes).
Heads Up
The machine's "High" temperature setting is optimized for espresso and may not produce steaming-hot Americano-style drinks. For those, use the hot water function after brewing to add heat. Avoid running multiple cups back-to-back without a brief recovery period, as the thermoblock needs time to reheat.