diff --git a/code/espurna/espurna.ino b/code/espurna/espurna.ino
index 50d8fa19..24a35b8e 100644
--- a/code/espurna/espurna.ino
+++ b/code/espurna/espurna.ino
@@ -204,56 +204,60 @@ void welcome() {
         DEBUG_MSG_P(PSTR(" WEB"));
     #endif
 
-    DEBUG_MSG_P(PSTR("\n[INIT] SENSORS:"));
+    #if SENSOR_SUPPORT
 
-    #if ANALOG_SUPPORT
-        DEBUG_MSG_P(PSTR(" ANALOG"));
-    #endif
-    #if BMX280_SUPPORT
-        DEBUG_MSG_P(PSTR(" BMX280"));
-    #endif
-    #if DALLAS_SUPPORT
-        DEBUG_MSG_P(PSTR(" DALLAS"));
-    #endif
-    #if DHT_SUPPORT
-        DEBUG_MSG_P(PSTR(" DHTXX"));
-    #endif
-    #if DIGITAL_SUPPORT
-        DEBUG_MSG_P(PSTR(" DIGITAL"));
-    #endif
-    #if ECH1560_SUPPORT
-        DEBUG_MSG_P(PSTR(" ECH1560"));
-    #endif
-    #if EMON_ADC121_SUPPORT
-        DEBUG_MSG_P(PSTR(" EMON_ADC121"));
-    #endif
-    #if EMON_ADS1X15_SUPPORT
-        DEBUG_MSG_P(PSTR(" EMON_ADX1X15"));
-    #endif
-    #if EMON_ANALOG_SUPPORT
-        DEBUG_MSG_P(PSTR(" EMON_ANALOG"));
-    #endif
-    #if EVENTS_SUPPORT
-        DEBUG_MSG_P(PSTR(" EVENTS"));
-    #endif
-    #if HLW8012_SUPPORT
-        DEBUG_MSG_P(PSTR(" HLW8012"));
-    #endif
-    #if MHZ19_SUPPORT
-        DEBUG_MSG_P(PSTR(" MHZ19"));
-    #endif
-    #if PMSX003_SUPPORT
-        DEBUG_MSG_P(PSTR(" PMSX003"));
-    #endif
-    #if SHT3X_I2C_SUPPORT
-        DEBUG_MSG_P(PSTR(" SHT3X_I2C"));
-    #endif
-    #if SI7021_SUPPORT
-        DEBUG_MSG_P(PSTR(" SI7021"));
-    #endif
-    #if V9261F_SUPPORT
-        DEBUG_MSG_P(PSTR(" V9261F"));
-    #endif
+        DEBUG_MSG_P(PSTR("\n[INIT] SENSORS:"));
+
+        #if ANALOG_SUPPORT
+            DEBUG_MSG_P(PSTR(" ANALOG"));
+        #endif
+        #if BMX280_SUPPORT
+            DEBUG_MSG_P(PSTR(" BMX280"));
+        #endif
+        #if DALLAS_SUPPORT
+            DEBUG_MSG_P(PSTR(" DALLAS"));
+        #endif
+        #if DHT_SUPPORT
+            DEBUG_MSG_P(PSTR(" DHTXX"));
+        #endif
+        #if DIGITAL_SUPPORT
+            DEBUG_MSG_P(PSTR(" DIGITAL"));
+        #endif
+        #if ECH1560_SUPPORT
+            DEBUG_MSG_P(PSTR(" ECH1560"));
+        #endif
+        #if EMON_ADC121_SUPPORT
+            DEBUG_MSG_P(PSTR(" EMON_ADC121"));
+        #endif
+        #if EMON_ADS1X15_SUPPORT
+            DEBUG_MSG_P(PSTR(" EMON_ADX1X15"));
+        #endif
+        #if EMON_ANALOG_SUPPORT
+            DEBUG_MSG_P(PSTR(" EMON_ANALOG"));
+        #endif
+        #if EVENTS_SUPPORT
+            DEBUG_MSG_P(PSTR(" EVENTS"));
+        #endif
+        #if HLW8012_SUPPORT
+            DEBUG_MSG_P(PSTR(" HLW8012"));
+        #endif
+        #if MHZ19_SUPPORT
+            DEBUG_MSG_P(PSTR(" MHZ19"));
+        #endif
+        #if PMSX003_SUPPORT
+            DEBUG_MSG_P(PSTR(" PMSX003"));
+        #endif
+        #if SHT3X_I2C_SUPPORT
+            DEBUG_MSG_P(PSTR(" SHT3X_I2C"));
+        #endif
+        #if SI7021_SUPPORT
+            DEBUG_MSG_P(PSTR(" SI7021"));
+        #endif
+        #if V9261F_SUPPORT
+            DEBUG_MSG_P(PSTR(" V9261F"));
+        #endif
+
+    #endif // SENSOR_SUPPORT
 
     DEBUG_MSG_P(PSTR("\n\n"));
 
diff --git a/code/espurna/filters/BaseFilter.h b/code/espurna/filters/BaseFilter.h
index fb422c32..ac693bb8 100644
--- a/code/espurna/filters/BaseFilter.h
+++ b/code/espurna/filters/BaseFilter.h
@@ -3,6 +3,8 @@
 // Copyright (C) 2017 by Xose Pérez <xose dot perez at gmail dot com>
 // -----------------------------------------------------------------------------
 
+#if SENSOR_SUPPORT
+
 #pragma once
 
 #include <vector>
@@ -46,3 +48,5 @@ class BaseFilter {
         std::vector<double> _data;
 
 };
+
+#endif // SENSOR_SUPPORT
diff --git a/code/espurna/filters/MaxFilter.h b/code/espurna/filters/MaxFilter.h
index 683e58f6..4121787d 100644
--- a/code/espurna/filters/MaxFilter.h
+++ b/code/espurna/filters/MaxFilter.h
@@ -3,6 +3,8 @@
 // Copyright (C) 2017 by Xose Pérez <xose dot perez at gmail dot com>
 // -----------------------------------------------------------------------------
 
+#if SENSOR_SUPPORT
+
 #pragma once
 
 #include <vector>
@@ -17,3 +19,5 @@ class MaxFilter : public BaseFilter {
         }
 
 };
+
+#endif // SENSOR_SUPPORT
diff --git a/code/espurna/filters/MedianFilter.h b/code/espurna/filters/MedianFilter.h
index 531252a4..06295c85 100644
--- a/code/espurna/filters/MedianFilter.h
+++ b/code/espurna/filters/MedianFilter.h
@@ -3,6 +3,8 @@
 // Copyright (C) 2017 by Xose Pérez <xose dot perez at gmail dot com>
 // -----------------------------------------------------------------------------
 
+#if SENSOR_SUPPORT
+
 #pragma once
 
 #include "BaseFilter.h"
@@ -58,3 +60,5 @@ class MedianFilter : public BaseFilter {
         }
 
 };
+
+#endif // SENSOR_SUPPORT
diff --git a/code/espurna/filters/MovingAverageFilter.h b/code/espurna/filters/MovingAverageFilter.h
index 0c48eff9..ce00dea7 100644
--- a/code/espurna/filters/MovingAverageFilter.h
+++ b/code/espurna/filters/MovingAverageFilter.h
@@ -3,6 +3,8 @@
 // Copyright (C) 2017 by Xose Pérez <xose dot perez at gmail dot com>
 // -----------------------------------------------------------------------------
 
+#if SENSOR_SUPPORT
+
 #pragma once
 
 #include <vector>
@@ -26,7 +28,7 @@ class MovingAverageFilter : public BaseFilter {
             }
 
             _pointer++;
-            
+
         }
 
         void reset() {
@@ -58,3 +60,5 @@ class MovingAverageFilter : public BaseFilter {
         double _sum = 0;
 
 };
+
+#endif // SENSOR_SUPPORT
diff --git a/code/espurna/mdns.ino b/code/espurna/mdns.ino
index 4c185674..1cdc689e 100644
--- a/code/espurna/mdns.ino
+++ b/code/espurna/mdns.ino
@@ -16,9 +16,9 @@ WiFiEventHandler _mdns_wifi_onAP;
 #if MQTT_SUPPORT
 void mdnsFindMQTT() {
     int count = MDNS.queryService("mqtt", "tcp");
-    DEBUG_MSG_P("[MQTT] MQTT brokers found: %d\n", count);
+    DEBUG_MSG_P(PSTR("[MQTT] MQTT brokers found: %d\n"), count);
     for (int i=0; i<count; i++) {
-        DEBUG_MSG_P("[MQTT] Broker at %s:%d\n", MDNS.IP(i).toString().c_str(), MDNS.port(i));
+        DEBUG_MSG_P(PSTR("[MQTT] Broker at %s:%d\n"), MDNS.IP(i).toString().c_str(), MDNS.port(i));
         mqttSetBrokerIfNone(MDNS.IP(i), MDNS.port(i));
     }
 }
diff --git a/code/espurna/mqtt.ino b/code/espurna/mqtt.ino
index 8e5f78ec..277d7010 100644
--- a/code/espurna/mqtt.ino
+++ b/code/espurna/mqtt.ino
@@ -65,7 +65,7 @@ bool mqttConnected() {
 
 void mqttDisconnect() {
     if (_mqtt.connected()) {
-        DEBUG_MSG_P("[MQTT] Disconnecting\n");
+        DEBUG_MSG_P(PSTR("[MQTT] Disconnecting\n"));
         _mqtt.disconnect();
     }
 }
@@ -148,7 +148,7 @@ void mqttSend(const char * topic, const char * message, bool force) {
         element.message = strdup(message);
         _mqtt_queue.push_back(element);
         _mqtt_flush_ticker.once_ms(MQTT_USE_JSON_DELAY, _mqttFlush);
-        
+
     } else {
         String path = _mqtt_topic + String(topic) + _mqtt_getter;
         mqttSendRaw(path.c_str(), message);
diff --git a/code/espurna/sensor.ino b/code/espurna/sensor.ino
index 4d3e0859..c100825c 100644
--- a/code/espurna/sensor.ino
+++ b/code/espurna/sensor.ino
@@ -183,7 +183,7 @@ void _sensorPre() {
     for (unsigned char i=0; i<_sensors.size(); i++) {
         _sensors[i]->pre();
         if (!_sensors[i]->status()) {
-            DEBUG_MSG("[SENSOR] Error reading data from %s (error: %d)\n",
+            DEBUG_MSG_P(PSTR("[SENSOR] Error reading data from %s (error: %d)\n"),
                 _sensors[i]->description().c_str(),
                 _sensors[i]->error()
             );
@@ -454,8 +454,8 @@ void _magnitudesInit() {
 
         BaseSensor * sensor = _sensors[i];
 
-        DEBUG_MSG("[SENSOR] %s\n", sensor->description().c_str());
-        if (sensor->error() != 0) DEBUG_MSG("[SENSOR]  -> ERROR %d\n", sensor->error());
+        DEBUG_MSG_P(PSTR("[SENSOR] %s\n"), sensor->description().c_str());
+        if (sensor->error() != 0) DEBUG_MSG_P(PSTR("[SENSOR]  -> ERROR %d\n"), sensor->error());
 
         for (unsigned char k=0; k<sensor->count(); k++) {
 
@@ -479,7 +479,7 @@ void _magnitudesInit() {
             }
             _magnitudes.push_back(new_magnitude);
 
-            DEBUG_MSG("[SENSOR]  -> %s:%d\n", _magnitudeTopic(type).c_str(), _counts[type]);
+            DEBUG_MSG_P(PSTR("[SENSOR]  -> %s:%d\n"), _magnitudeTopic(type).c_str(), _counts[type]);
 
             _counts[type] = _counts[type] + 1;
 
@@ -595,7 +595,7 @@ void sensorLoop() {
                 #if SENSOR_DEBUG
                 {
                     dtostrf(current, 1-sizeof(buffer), decimals, buffer);
-                    DEBUG_MSG("[SENSOR] %s - %s: %s%s\n",
+                    DEBUG_MSG_P(PSTR("[SENSOR] %s - %s: %s%s\n"),
                         magnitude.sensor->slot(magnitude.local).c_str(),
                         _magnitudeTopic(magnitude.type).c_str(),
                         buffer,
diff --git a/code/espurna/sensors/BMX280Sensor.h b/code/espurna/sensors/BMX280Sensor.h
index 840b45d6..29d5aa2f 100644
--- a/code/espurna/sensors/BMX280Sensor.h
+++ b/code/espurna/sensors/BMX280Sensor.h
@@ -248,4 +248,4 @@ class BMX280Sensor : public I2CSensor {
 
 unsigned char BMX280Sensor::addresses[2] = {0x76, 0x77};
 
-// SENSOR_SUPPORT && BMX280_SUPPORT
+#endif // SENSOR_SUPPORT && BMX280_SUPPORT
diff --git a/code/espurna/sensors/ECH1560Sensor.h b/code/espurna/sensors/ECH1560Sensor.h
index 67a97ea3..c4b87cbc 100644
--- a/code/espurna/sensors/ECH1560Sensor.h
+++ b/code/espurna/sensors/ECH1560Sensor.h
@@ -311,7 +311,7 @@ void ECH1560Sensor::_attach(ECH1560Sensor * instance, unsigned char gpio, unsign
     _ech1560_sensor_instance[index] = instance;
     attachInterrupt(gpio, _ech1560_sensor_isr_list[index], mode);
     #if SENSOR_DEBUG
-        DEBUG_MSG("[SENSOR] GPIO%d interrupt attached to %s\n", gpio, instance->description().c_str());
+        DEBUG_MSG_P(PSTR("[SENSOR] GPIO%d interrupt attached to %s\n"), gpio, instance->description().c_str());
     #endif
 }
 
@@ -321,7 +321,7 @@ void ECH1560Sensor::_detach(unsigned char gpio) {
     if (_ech1560_sensor_instance[index]) {
         detachInterrupt(gpio);
         #if SENSOR_DEBUG
-            DEBUG_MSG("[SENSOR] GPIO%d interrupt detached from %s\n", gpio, _ech1560_sensor_instance[index]->description().c_str());
+            DEBUG_MSG_P(PSTR("[SENSOR] GPIO%d interrupt detached from %s\n"), gpio, _ech1560_sensor_instance[index]->description().c_str());
         #endif
         _ech1560_sensor_instance[index] = NULL;
     }
diff --git a/code/espurna/sensors/EventSensor.h b/code/espurna/sensors/EventSensor.h
index 6af9270d..c593be04 100644
--- a/code/espurna/sensors/EventSensor.h
+++ b/code/espurna/sensors/EventSensor.h
@@ -185,7 +185,7 @@ void EventSensor::_attach(EventSensor * instance, unsigned char gpio, unsigned c
     _event_sensor_instance[index] = instance;
     attachInterrupt(gpio, _event_sensor_isr_list[index], mode);
     #if SENSOR_DEBUG
-        DEBUG_MSG("[SENSOR] GPIO%d interrupt attached to %s\n", gpio, instance->description().c_str());
+        DEBUG_MSG_P(PSTR("[SENSOR] GPIO%d interrupt attached to %s\n"), gpio, instance->description().c_str());
     #endif
 }
 
@@ -195,7 +195,7 @@ void EventSensor::_detach(unsigned char gpio) {
     if (_event_sensor_instance[index]) {
         detachInterrupt(gpio);
         #if SENSOR_DEBUG
-            DEBUG_MSG("[SENSOR] GPIO%d interrupt detached from %s\n", gpio, _event_sensor_instance[index]->description().c_str());
+            DEBUG_MSG_P(PSTR("[SENSOR] GPIO%d interrupt detached from %s\n"), gpio, _event_sensor_instance[index]->description().c_str());
         #endif
         _event_sensor_instance[index] = NULL;
     }
diff --git a/code/espurna/sensors/HLW8012Sensor.h b/code/espurna/sensors/HLW8012Sensor.h
index 59bebc6c..5a45241c 100644
--- a/code/espurna/sensors/HLW8012Sensor.h
+++ b/code/espurna/sensors/HLW8012Sensor.h
@@ -295,7 +295,7 @@ void HLW8012Sensor::_attach(HLW8012Sensor * instance, unsigned char gpio, unsign
     _hlw8012_sensor_instance[index] = instance;
     attachInterrupt(gpio, _hlw8012_sensor_isr_list[index], mode);
     #if SENSOR_DEBUG
-        DEBUG_MSG("[SENSOR] GPIO%d interrupt attached to %s\n", gpio, instance->description().c_str());
+        DEBUG_MSG_P(PSTR("[SENSOR] GPIO%d interrupt attached to %s\n"), gpio, instance->description().c_str());
     #endif
 }
 
@@ -305,7 +305,7 @@ void HLW8012Sensor::_detach(unsigned char gpio) {
     if (_hlw8012_sensor_instance[index]) {
         detachInterrupt(gpio);
         #if SENSOR_DEBUG
-            DEBUG_MSG("[SENSOR] GPIO%d interrupt detached from %s\n", gpio, _hlw8012_sensor_instance[index]->description().c_str());
+            DEBUG_MSG_P(PSTR("[SENSOR] GPIO%d interrupt detached from %s\n"), gpio, _hlw8012_sensor_instance[index]->description().c_str());
         #endif
         _hlw8012_sensor_instance[index] = NULL;
     }
diff --git a/code/espurna/sensors/I2CSensor.h b/code/espurna/sensors/I2CSensor.h
index 44057ee6..f4391d03 100644
--- a/code/espurna/sensors/I2CSensor.h
+++ b/code/espurna/sensors/I2CSensor.h
@@ -3,7 +3,7 @@
 // Copyright (C) 2017 by Xose Pérez <xose dot perez at gmail dot com>
 // -----------------------------------------------------------------------------
 
-#if SENSOR_SUPPORT && I2C_SUPPORT
+#if SENSOR_SUPPORT && ( I2C_SUPPORT || EMON_ANALOG_SUPPORT )
 
 #pragma once