Can the functionality of an electrically heated pitot-tube be verified using the aircraft's ammeter?

The functionality of an electrically heated pitot-tube can indeed be verified by observing the ammeter. When the heater is activated, it draws electrical current, which results in a deflection of the ammeter needle. This action indicates that the heater is operational and receiving power. The amount of current flow can be monitored to ensure that it is within expected parameters for the system. A positive deflection on the ammeter confirms that the circuit is complete and that the pitot-tube heater is functioning as intended.

Visual checks alone do not provide information on whether the heater is actually drawing current or functioning properly. Checking the temperature output requires additional equipment and does not offer immediate verification of current flow. Using a digital multimeter, while useful for precise electrical diagnostics, is not a standard method for verifying the heater's operation in routine checks. Thus, monitoring the ammeter is the most straightforward and effective method for this purpose.