A chamberless indoor air quality monitor system includes a detector body. A resistive heater is operatively connected to the detector body. An active temperature sensor operatively connected to the resistive heater and operatively connected to an outer surface of the detector body configured to take an active temperature measurement. A method for measuring temperature in a chamberless indoor air quality monitor system includes generating an active temperature measurement with an active temperature sensor operatively connected to an outer surface of the detector body. The method includes heating the active temperature sensor with a resistive heater operatively connected to the detector body. The method includes comparing the active temperature measurements to one another to generate a corrected active temperature measurement based on a temperature difference over time between one or more of the active temperature measurements.