diff --git a/co2_sensor.cpp b/co2_sensor.cpp
index f800bd25cf3c9ec882e002e5e04c8d0e8e3ebf14..a51036a1fcf2b445da005988469d2d9d9f923e63 100644
--- a/co2_sensor.cpp
+++ b/co2_sensor.cpp
@@ -84,6 +84,8 @@ namespace sensor {
     static int16_t previous_co2 = 0;
     if (co2 > (previous_co2 - 30) && co2 < (previous_co2 + 30)) {
       stable_measurements++;
+      Serial.print("Stable since : ");
+      Serial.println(stable_measurements);
       waiting_color = color::green;
     } else {
       stable_measurements = 0;
@@ -142,7 +144,9 @@ namespace sensor {
      * Fresh data. Show it and send it if needed.
      */
     if (freshData) {
-      countStableMeasurements();
+      if (should_calibrate) {
+        countStableMeasurements();
+      }
       timestamp = ntp::getLocalTime();
       Serial.println(timestamp);