A method, including ejecting irrigation fluid from a distal end of a probe so as to irrigate tissue, and receiving, over a period of time, initial signals indicative of respective temperatures of the distal end, from a temperature sensor in the distal end. The method also includes formulating from the initial signals a temperature range between upper and lower temperature thresholds and, when a further signal from the temperature sensor, received subsequent to the period of time, is indicative of a further temperature above the upper temperature threshold, raising an alarm that a bubble is present in the irrigation fluid.

A method, including ejecting irrigation fluid from a distal end of a probe so as to irrigate tissue, and receiving, over a period of time, initial signals indicative of respective temperatures of the distal end, from a temperature sensor in the distal end. The method also includes formulating from the initial signals a temperature range between upper and lower temperature thresholds and, when a further signal from the temperature sensor, received subsequent to the period of time, is indicative of a further temperature above the upper temperature threshold, raising an alarm that a bubble is present in the irrigation fluid.

A method, including ejecting irrigation fluid from a distal end of a probe so as to irrigate tissue, and receiving, over a period of time, initial signals indicative of respective temperatures of the distal end, from a temperature sensor in the distal end. The method also includes formulating from the initial signals a temperature range between upper and lower temperature thresholds and, when a further signal from the temperature sensor, received subsequent to the period of time, is indicative of a further temperature above the upper temperature threshold, raising an alarm that a bubble is present in the irrigation fluid.

A method, including ejecting irrigation fluid from a distal end of a probe so as to irrigate tissue, and receiving, over a period of time, initial signals indicative of respective temperatures of the distal end, from a temperature sensor in the distal end. The method also includes formulating from the initial signals a temperature range between upper and lower temperature thresholds and, when a further signal from the temperature sensor, received subsequent to the period of time, is indicative of a further temperature above the upper temperature threshold, raising an alarm that a bubble is present in the irrigation fluid.

A thermal-type flow-rate sensor includes a substrate and a detection unit that is supported by the substrate and at least an upper surface of which is exposed to a flow of a fluid. The detection unit includes: an insulating layer, a heating element arranged on an upper surface of the insulating layer, an upstream temperature measurement element that is arranged on the upper surface of the insulating layer upstream of the heating element in the flow direction that includes a pyroelectric layer, and a downstream temperature measurement element arranged on the upper surface of the insulating layer so as to be positioned downstream of the heating element in the flow direction and that includes a pyroelectric layer.