Failure Connection (Honeywell WIFI Thermostat)

[prosportal]

I have had a Honeywell Wi-Fi Thermostat (RTH6580WF) for a number of years now. Within the past 6 months, I purchased a Nighthawk R6400. Since then, i always get "Connection Failure" on my thermostat; despite doing numerous resets.

Today, I decided to fire up my phone's hotspot and try to register the thermostat through that wireless SSID and it worked like a charm. That leads me to believe there's something not configured correctly on the router itself.

Has anyone else seen this and could you offer a solution?

Wireless Setup:

Broadcasting SSID

Channel: auto

Mode: Up to 450Mbps

Security:

WPA2-PSK[AES]

[duckware · Accepted solution]

Try dropping 2.4 GHz mode mode from "450 Mbps" to something lower (changes from 40Mhz mode possible to 20Mhz mode)?

[michaelkenward]

These things usually come down to the device you are trying to connect.

Have you sought help in the places where they support the Honeywell Wi-Fi Thermostat?

[prosportal]

I have not. I began this troubleshooting expedition by connecting it successfully to other routers. So far, I have been successful on a Linksys router and my phone's hotspot, but the thermostat will not connect to my nighthawk router's wifi. Therefore, I have reached out for assintance on this forum first.

[FURRYe38]

Try setting manual channel 1, 6 or 11 on 2.4Ghz. 

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@prosportalwrote:

I have not. I began this troubleshooting expedition by connecting it successfully to other routers. So far, I have been successful on a Linksys router and my phone's hotspot, but the thermostat will not connect to my nighthawk router's wifi. Therefore, I have reached out for assintance on this forum first.

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[duckware · Accepted solution]

Try dropping 2.4 GHz mode mode from "450 Mbps" to something lower (changes from 40Mhz mode possible to 20Mhz mode)?

[prosportal]

So, it looks like this thermostat will ONLY work on "Up to 54mbps" which has a negative impact on all my other devices, but suppose that's the limitation of wireless- G

[FURRYe38]

The router should be able to handle 54Mb for some devices and up up higher speeds for others. 

Be sure to set WPA and WPA2 and AUTO and see. 

[prosportal]

Official response:

Thank you for contacting Honeywell.

We sincerely regret the inconvenience caused.

Honeywell thermostats only operate on the 2.4GHz range meaning they are only compatible with wireless 802.11 b/g/n.

They are not compatible with the 5GHz networks, 802.11 n/ac. There is not a need for this compatibility since the thermostat is a low bandwidth device. Also, the 2.4GHz frequency gives a better distance and penetrating power vs the 5GHz range.

[michaelkenward]

That doesn't help. Of course they do not support 5 GHz. They simply won't see it or try to connect.

What you need to know is any restrictions on the 2.4 GHz. That is what @duckware is getting at.

[rtclemen]

I found this on the Honeywell website: https://yourhome.honeywell.com/en/questions/lyric-thermostat-compatibility-11

Afer my contractor and I spent several hours trying to get a Lyric T6 to connect, I checked my routers for Wi-Fi Alliance certification on their website (https://www.wi-fi.org/) and found that neither of the two are compatible.

Good luck!