diff --git a/sonoff/sonoff.ino b/sonoff/sonoff.ino
index 958c7879b..89badfbe1 100755
--- a/sonoff/sonoff.ino
+++ b/sonoff/sonoff.ino
@@ -914,7 +914,7 @@ void MqttDataHandler(char* topic, byte* data, unsigned int data_len)
       snprintf_P(mqtt_data, sizeof(mqtt_data), PSTR("%s}"), mqtt_data);
     }
     else if (CMND_PWMFREQUENCY == command_code) {
-      if ((1 == payload) || ((payload >= 100) && (payload <= 4000))) {
+      if ((1 == payload) || ((payload >= PWM_MIN) && (payload <= PWM_MAX))) {
         Settings.pwm_frequency = (1 == payload) ? PWM_FREQ : payload;
         analogWriteFreq(Settings.pwm_frequency);   // Default is 1000 (core_esp8266_wiring_pwm.c)
       }