External app problems for heating systems

[Vickie1971]

1. Security must be WPA2 (not 3). connect to WPA/WPA2, networks it won’t connect to  the newer WPA2-PSK/WPA3-SAE
2. Frequency must be set at 2.4GHz.
3. Broadcast channel cannot be the highest channel.
4. Signal strength must be very good. 
5. Try turning off any extenders or mesh Wi-Fi.
6. Try putting the phone into airplane mode first and then turning Wi-Fi back on before connecting.
7. Remove these special characters from the Home Network password:  / # @ %
8. If possible, disable Band Steering and create different SSID names for 2.4GHz and 5GHz.
9. Make sure Multicast Enhancement is enabled.

[TimmyBGood]

@Vickie1971 

Those are presumably the manufacturer suggestions: which have you tried?

The first one is rather odd: any modern system really should support WPA2-PSK because all wireless security below that level is known to be flawed.  WPA2-TKIP has been exploitable for about 15 years.