Systems and methods implementing a
frost sensor comprising a substrate (S); and sub-sensors disposed on the substrate. The sub-sensors comprising: a resistance-based sub-sensor (
RSS) formed of a first trace disposed on S in a winding pattern and configured to measure a temperature; a
capacitance-based sub-sensor formed of a second trace defining a first
electrode and a third trace defining a second
electrode (wherein (i) the first and second electrodes comprise interdigitated fingers or other interdigitated structures (including, but not limited to, round, spiral interdigitated electrodes, etc.) configured to detect a change in
capacitance due of
frost, ice or water, and (ii) the second trace is integrally formed with the first trace); and another
RSS formed of a fourth trace defining a third
electrode and a fifth trace defining a fourth electrode (wherein (i) the third and fourth electrodes comprise interdigitated fingers or other interdigitated structures (including, but not limited to, round, spiral interdigitated electrodes, etc.) configured to detect a change in resistance due to the
frost, ice or water, and (ii) the fourth trace is integrally formed with the third trace).