A flow-through fluid heater comprises: a high thermal conductivity conduit-defining body shaped to provide a conduit that extends between an inlet port and an outlet port; one or more heating elements connected to the body for providing heat to the body, thereby permitting the body to provide heat to fluid flowing through the conduit; a temperature sensor connected to sense a measured temperature indicative of a temperature of the fluid in a vicinity of the temperature sensor; one or more flow rate sensors for sensing a measured flow rate of the fluid through the conduit; and a controller connected to receive signals from the temperature sensor and the flow rate sensors, the controller configured to control an amount of heat energy imparted to the fluid during a period that the fluid is resident in the conduit between the inlet port and the outlet port based at least in part on the measured temperature and the measured flow rate.