MULTIHEAT

MULTIHEAT is a dual-function kitchen appliance that combines a sandwich toaster and a low-temperature food dehydrator within a single compact device. The project reinterprets a familiar household product as a multifunctional food preparation system, addressing both limited kitchen space and the increasing demand for healthier, homemade snacks.

The concept is based on the observation that many domestic appliances are designed for single-purpose use. Sandwich toasters, in particular, operate for short cooking periods and remain unused for most of the day. MULTIHEAT enhances the functionality of this common appliance by introducing a secondary mode that enables continuous, low-temperature food processing.

Technically, the device operates across two distinct temperature regimes optimized for different preparation methods. In grilling mode, the system functions between 180–220°C using a 1000 W nickel-chromium heating element positioned beneath a granite cooking plate. The granite surface provides high thermal mass, stabilizing temperature fluctuations and ensuring even heat distribution across the cooking area.

A reflective glass lid improves thermal efficiency by redirecting heat back into the chamber while retaining warm air within the enclosed space. This reduces heat loss and supports consistent cooking performance.

For dehydration, the appliance incorporates a modular system consisting of a perforated metal plate that elevates food above the heating surface. This structure prevents direct heat contact while allowing warm air to circulate evenly around sliced fruits and vegetables.

The dehydration process is supported by a detachable front module equipped with a fan unit. Connected via a USB-C interface, this module provides both power and communication with the main body. The fan-assisted airflow system draws in ambient air, heats it through the resistance element, and distributes it evenly within the chamber using a 12–24 V configuration.

Two temperature ranges support varied drying needs. The 40–60°C range enables slow dehydration to preserve nutrients and flavor, while the 60–80°C range allows faster moisture removal.