My friend, I have the same problem, but on the contrary: in my house the wi-fi does not connect at all .. already in other places, it connects normally.
In my case, I have a TP-LINK WR740N router and it does not connect at all (I've already changed the SSID name, I've already changed the password, I've already left it open ...) I did not get it at all.
Strange that, in my girlfriend's house, it has the same router model, which I configured the same way as mine, and there my raspberry connects normally.
Everything leads to believe that my router has some problem to connect to raspberry Pi 3 by wifi.
If your router is of this model, I recommend switching or testing with another to see ....