Classe 300EOS with Netatmo can be connected to wired LAN network in the house or wireless. If there is no network in the house, you can connect directly to it (it generates authomatically the Wi-Fi). And Home + Project must be connected to the same network.
In case of wireless connection: the house network must be 2.4GHz 802.11 b/g/n type.
5GHz type networks are not compatible.