ESP8266 - 01 DHT11 Problem

Hi community, I'm working on esp8266 but I have a problem; I'm sending the data I read from DHT11 to mysql, and there's no problem here, it just sends a nan value and a value of 0 every once in a while in the data I send.I'd appreciate it if you'd help.

  • Im using Adafruit DHT library.
#ifdef ESP32
#include <WiFi.h>
#include <HTTPClient.h>
#else
#include <ESP8266WiFi.h>
#include <ESP8266HTTPClient.h>
#include <WiFiClient.h>
#endif

#include <Wire.h>
#include "DHT.h"
#define DHTPIN 2

#define DHTTYPE DHT11
DHT dht(DHTPIN, DHTTYPE);


const char* ssid     = "EA Research Center";
const char* password = "******";

const char* serverName = "***************";

String apiKeyValue = "*********";

String sensorName = "DHT";
String sensorLocation = "KÖLN";
String deviceID = "1";
//String testv1 = "3";
//String testv2 = "3";
//String testv3 = "3";

void setup() {
  Serial.begin(115200);

  dht.begin();
  WiFi.begin(ssid, password);
  Serial.println("Connecting");
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("");
  Serial.print("Connected to WiFi network with IP Address: ");
  Serial.println(WiFi.localIP());
}

void loop() {
  //Check WiFi connection status
  
  if (WiFi.status() == WL_CONNECTED) {
    dht.begin();
    HTTPClient http;


    http.begin(serverName);

    
    http.addHeader("Content-Type", "application/x-www-form-urlencoded");

   
    String httpRequestData = "api_key=" + apiKeyValue + "&sensor=" + sensorName
                             + "&location=" + sensorLocation + "&value1=" + String(dht.readTemperature())
                             + "&value2=" + String(dht.readHumidity())  + "&value3=" + deviceID + "";
    Serial.print("httpRequestData: ");
    Serial.println(httpRequestData);

    // Send HTTP POST request
    int httpResponseCode = http.POST(httpRequestData);


    if (httpResponseCode > 0) {
      Serial.print("HTTP Response code: ");
      Serial.println(httpResponseCode);
    }
    else {
      Serial.print("Error code: ");
      Serial.println(httpResponseCode);
    }
    
    http.end();
  }
  else {
    Serial.println("WiFi Disconnected");
  }
  //Send an HTTP POST request every 30 seconds
  delay(30000);
}

I'm sending the data I read from DHT11 to mysql, and there's no problem here, it just sends a nan value and a value of 0 every once in a while

So is the data received from the DHT correct ?