Cannot modify the private value in member function of the class - c++

Question

I am wondering what is going on in my app.
The problem is that I cannot modify one of my private values (temperature) from the class Room while the other private one (targetTemp) changes without any problems.
I've got a function setTargetTemp where I can assign the value for targetTemp - works (Room.cpp line 18-20).
I've got another function outsideImpact where I can assign the value for temperature - doesn't work (Room.cpp line 21-27). The method is the same (excluding some calculations).
In main.cpp I called both functions (line 15 and 16) in a loop. While debugging I can see that livingRoom's temperature remains the same at every iteration, targetTemp on the other hand is changing as expected.
So what is the difference? What am I missing here?
Room.h
class Room {
private:
float
temperature, // Temperature in the room
targetTemp, // Target temperature in the room
factor; // Susceptibility of the room to cooling/heating - 1 is default, +- 0.25 = ~ 1.5 C-deg / >1 - faster
public:
Room(void);
~Room(void);
float getTemp(void);
float getTargetTemp(void);
void setTargetTemp(float target);
void outsideImpact(float outsideTemp);
};
Room.cpp
#include "./Room.h"
#include <iostream>
#include <cmath>
Room::Room(void) {
temperature = 15.;
targetTemp = 22.;
factor = 1;
}
Room::~Room(void) {}
float Room::getTemp(void) {
return temperature;
}
float Room::getTargetTemp(void) {
return targetTemp;
}
void Room::setTargetTemp(float target) {
targetTemp = target;
}
void Room::outsideImpact(float outsideTemp) {
float trendValue = (abs(temperature - outsideTemp) / 100 * factor);
if(temperature > outsideTemp)
temperature -= trendValue;
else
temperature += trendValue;
}
main.cpp
#include "./Room.h"
#include <iostream>
#include <cmath>
using namespace std;
int main(void){
float
timer = 0.,
outsideTemp = -10.;
Room livingRoom;
do {
timer += 0.25;
livingRoom.outsideImpact(outsideTemp); // change the "temperature"
livingRoom.setTargetTemp(26.+timer); // change the "targetTemp"
cout << "Living room temp: " << livingRoom.getTemp() << " || Outside temp: " << outsideTemp
<< " || Time: " << timer << " hour(s)" << "\t|| TARGET: " << livingRoom.getTargetTemp() << endl;
} while (round(livingRoom.getTemp()) != round(outsideTemp));
return 0;
}