ok. but what i do notunderstand is…
if its working its working. that means i can send commands and the maxxair receives them every time. next day (or few hours later) nothing works. even if i send the same command 100 times. there is not one time that it will work.
i installed the esp with the transmitter directly in front of the ir light into the frame of the maxxair, and i put the ir light from outside of the case of the maxxair into the frame of the maxxair (where i also put the esp). so there is no sunlight and its really really close to each other. maybe there are some other LEDs, i dont know. i have to try to put them outside where i can see whats gonna happen. but no time for that now. even if it really sucks to stand up to control the maxxair at the moment 
@Karosm what transistor or what transmitter should i use to get good results?