Nice but a new controller is a kick in the teeth.
Excellent quiet, very quiet fan. Lovely bit of kit. But it's controller can be very dodgy and common problems with the humidity and temp controller run together, of it turning extract off if humidity low, both fans in fact, or start stopping, etc. So they released, hey presto, and NEW Fan Controller, because this one is pants. Get the S4 instead and an S6, or 2 s6Cloudlines if you have the room, and buy the new smart controller. Sorry I got the T4 but i needed a silent fan, so just run it dumb. There were no S4s as theyre as rare as rocking horse poo poo.