diff --git a/examples/BresserWeatherSensorMQTTCustom/src/WeatherSensor.cpp b/examples/BresserWeatherSensorMQTTCustom/src/WeatherSensor.cpp
index 0ccfb3ea..fcdeb05e 100644
--- a/examples/BresserWeatherSensorMQTTCustom/src/WeatherSensor.cpp
+++ b/examples/BresserWeatherSensorMQTTCustom/src/WeatherSensor.cpp
@@ -255,7 +255,7 @@ bool WeatherSensor::getData(uint32_t timeout, uint8_t flags, uint8_t type, void
             bool all_slots_valid = true;
             bool all_slots_complete = true;
 
-            for (int i = 0; i < sensor.size(); i++)
+            for (size_t i = 0; i < sensor.size(); i++)
             {
                 if (!sensor[i].valid)
                 {
@@ -291,7 +291,7 @@ bool WeatherSensor::getData(uint32_t timeout, uint8_t flags, uint8_t type, void
                     radio.standby();
                     return true;
                 }
-            } // for (int i=0; i<sensor.size(); i++)
+            } // for (size_t i=0; i<sensor.size(); i++)
 
             // All slots required (valid AND complete)
             if ((flags & DATA_ALL_SLOTS) && all_slots_valid && all_slots_complete)
@@ -509,7 +509,7 @@ int WeatherSensor::findSlot(uint32_t id, DecodeStatus *status)
     // Search all slots
     int free_slot = -1;
     int update_slot = -1;
-    for (int i = 0; i < sensor.size(); i++)
+    for (size_t i = 0; i < sensor.size(); i++)
     {
         log_d("sensor[%d]: v=%d id=0x%08X t=%d c=%d", i, sensor[i].valid, (unsigned int)sensor[i].sensor_id, sensor[i].s_type, sensor[i].complete);
 
@@ -554,7 +554,7 @@ int WeatherSensor::findSlot(uint32_t id, DecodeStatus *status)
 //
 int WeatherSensor::findId(uint32_t id)
 {
-    for (int i = 0; i < sensor.size(); i++)
+    for (size_t i = 0; i < sensor.size(); i++)
     {
         if (sensor[i].valid && (sensor[i].sensor_id == id))
             return i;
@@ -567,7 +567,7 @@ int WeatherSensor::findId(uint32_t id)
 //
 int WeatherSensor::findType(uint8_t type, uint8_t ch)
 {
-    for (int i = 0; i < sensor.size(); i++)
+    for (size_t i = 0; i < sensor.size(); i++)
     {
         if (sensor[i].valid && (sensor[i].s_type == type) &&
             ((ch == 0xFF) || (sensor[i].chan = ch)))
diff --git a/examples/BresserWeatherSensorMQTTCustom/src/WeatherSensor.h b/examples/BresserWeatherSensorMQTTCustom/src/WeatherSensor.h
index b5f59c8c..0c9efd8e 100644
--- a/examples/BresserWeatherSensorMQTTCustom/src/WeatherSensor.h
+++ b/examples/BresserWeatherSensorMQTTCustom/src/WeatherSensor.h
@@ -349,7 +349,7 @@ class WeatherSensor {
         */
         void clearSlots(uint8_t type = 0xFF)
         {
-            for (int i=0; i<sensor.size(); i++) {
+            for (size_t i=0; i<sensor.size(); i++) {
                 if ((type == 0xFF) || (sensor[i].s_type == type)) {
                     sensor[i].valid    = false;
                     sensor[i].complete = false;
diff --git a/library.properties b/library.properties
index 55523c71..a04acb97 100644
--- a/library.properties
+++ b/library.properties
@@ -1,5 +1,5 @@
 name=BresserWeatherSensorReceiver
-version=0.28.0
+version=0.28.1
 author=Matthias Prinke <matthias-bs@web.de>
 maintainer=Matthias Prinke <matthias-bs@web.de>
 sentence=Bresser 5-in-1/6-in-1/7-in-1 868 MHz Weather Sensor Radio Receiver for Arduino based on CC1101, SX1276/RFM95W or SX1262.
diff --git a/package.json b/package.json
index 8f73325a..5b1db370 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "BresserWeatherSensorReceiver",
-  "version": "0.28.0",
+  "version": "0.28.1",
   "description": "Bresser 5-in-1/6-in-1/7-in-1 868 MHz Weather Sensor Radio Receiver for Arduino based on CC1101, SX1276/RFM95W or SX1262",
   "main": "WeatherSensor.cpp",
   "frameworks": "arduino",
diff --git a/src/WeatherSensor.cpp b/src/WeatherSensor.cpp
index 0ccfb3ea..fcdeb05e 100644
--- a/src/WeatherSensor.cpp
+++ b/src/WeatherSensor.cpp
@@ -255,7 +255,7 @@ bool WeatherSensor::getData(uint32_t timeout, uint8_t flags, uint8_t type, void
             bool all_slots_valid = true;
             bool all_slots_complete = true;
 
-            for (int i = 0; i < sensor.size(); i++)
+            for (size_t i = 0; i < sensor.size(); i++)
             {
                 if (!sensor[i].valid)
                 {
@@ -291,7 +291,7 @@ bool WeatherSensor::getData(uint32_t timeout, uint8_t flags, uint8_t type, void
                     radio.standby();
                     return true;
                 }
-            } // for (int i=0; i<sensor.size(); i++)
+            } // for (size_t i=0; i<sensor.size(); i++)
 
             // All slots required (valid AND complete)
             if ((flags & DATA_ALL_SLOTS) && all_slots_valid && all_slots_complete)
@@ -509,7 +509,7 @@ int WeatherSensor::findSlot(uint32_t id, DecodeStatus *status)
     // Search all slots
     int free_slot = -1;
     int update_slot = -1;
-    for (int i = 0; i < sensor.size(); i++)
+    for (size_t i = 0; i < sensor.size(); i++)
     {
         log_d("sensor[%d]: v=%d id=0x%08X t=%d c=%d", i, sensor[i].valid, (unsigned int)sensor[i].sensor_id, sensor[i].s_type, sensor[i].complete);
 
@@ -554,7 +554,7 @@ int WeatherSensor::findSlot(uint32_t id, DecodeStatus *status)
 //
 int WeatherSensor::findId(uint32_t id)
 {
-    for (int i = 0; i < sensor.size(); i++)
+    for (size_t i = 0; i < sensor.size(); i++)
     {
         if (sensor[i].valid && (sensor[i].sensor_id == id))
             return i;
@@ -567,7 +567,7 @@ int WeatherSensor::findId(uint32_t id)
 //
 int WeatherSensor::findType(uint8_t type, uint8_t ch)
 {
-    for (int i = 0; i < sensor.size(); i++)
+    for (size_t i = 0; i < sensor.size(); i++)
     {
         if (sensor[i].valid && (sensor[i].s_type == type) &&
             ((ch == 0xFF) || (sensor[i].chan = ch)))
diff --git a/src/WeatherSensor.h b/src/WeatherSensor.h
index b5f59c8c..0c9efd8e 100644
--- a/src/WeatherSensor.h
+++ b/src/WeatherSensor.h
@@ -349,7 +349,7 @@ class WeatherSensor {
         */
         void clearSlots(uint8_t type = 0xFF)
         {
-            for (int i=0; i<sensor.size(); i++) {
+            for (size_t i=0; i<sensor.size(); i++) {
                 if ((type == 0xFF) || (sensor[i].s_type == type)) {
                     sensor[i].valid    = false;
                     sensor[i].complete = false;