BH1750 stops giving readings

What is wrong with the code below.
It gives right readings only when fan is running.
In the first place I thought it was because of the missing delay, which I added first to 250, now 500. Still not working.
When fan stops, reading is 54612 in Blynk and same in serial monitor.
If I use simple example code from BH1750FVI, example, all works fine.
Do not understand.

#include <BlynkSimpleEsp8266.h>
#include "DHTesp.h"
#include "BH1750FVI.h"

char ssid[] = "X";
char pass[] = "Y";
char auth[] = "Z"; 

DHTesp dht;
BH1750FVI LightSensor(BH1750FVI::k_DevModeContLowRes);

float h;
float t;
uint16_t  lux;
boolean fanOn = false;

void setup() {
    Serial.begin(9600);
    LightSensor.begin(); 
    Blynk.begin(auth, ssid, pass);
    dht.setup(D4, DHTesp::DHT22);
    pinMode(D1, OUTPUT);
    digitalWrite(D1, HIGH);    
    Blynk.virtualWrite(V8, "Off");
}
 
void loop() {
    Blynk.run();
    h = dht.getHumidity();
    t = dht.getTemperature();
    lux = LightSensor.GetLightIntensity();
    Serial.print("{\"lux\": ");
    Serial.print(lux);
    Serial.print(", \"temp\": ");
    Serial.print(t);
    Serial.print("}\n");
    Blynk.virtualWrite(V5, t);
    Blynk.virtualWrite(V6, h);    
    Blynk.virtualWrite(V1, lux);
    delay(500);
      if (h > 50)
      {
        fanOn = true;     
        Blynk.virtualWrite(V8, "On");
      }    
      if (fanOn)
      {
        tuuleta();
      }
    }

    void tuuleta()
    {
      digitalWrite(D1, LOW); // start fan. Low trigger relay = LOW starts fan
      if (h < 40)
      {
        fanOn = false;
        Blynk.virtualWrite(V8, "Off");
        digitalWrite(D1, HIGH);      
      }
    }
    int ambient()
    {
      // Not in use yet
    }

Seems that when D1 goes high, BH1750 goes nuts, but why?

I really liked to get answer to this. Any hunch, Anyone?
I have tried more than one ESP8266 based board and all are failed the same way.
Also tried different pins. No success.
Arduino copy worked fine, but it has not wifi and I would not like to buy one because I'm pretty happy with the Wemos D1 R1 Mini and I'm waiting more copies to arrive.

Still struggling with this. I found another BH1750 library which I thought would work but no.

If someone gets BH1750 and DHT11/22 working together on a same ESP/Arduino board, I would be very pleased to know.
Or some other way to get temperature and lux, please tell me.
Thanks.