@HANSM 

Test other devices also connected to the router, if those work the Lennox could possibly being having DNS issues or it has a static IP configured. Try changing the network settings to DHCP.

HANSM wrote

Our Lennox icomfort-wifi thermostat is connected to the router but cannot access the internet

@HANSM 

All other devises work just fine. The router is set to dynamic IP and shows its IP as 68.110.114.225. The clients have 192.168.0.xxx with the Lennox as 192.168.0.100. The Lennox itself also shows that and it lists 192.168.0.1 as gateway and as DNS1.

@HANSM 

I would probably reach out to Lennox to see what else could be missing or needing to be configured. 

@HANSM 

I have the same problem with my Lennox iComfort thermostat.  I chose the 2.4G speed on my TP-Link AC1900 Archer 8 versus the 5G speed.  I am successfully able to connect to the modem but I can't get internet connection on the iComfort.  On the iComfort to choose a wireless network and password, I have the option to chose WEP, WPA, or WPA2 regarding secruity encription.  Do you know what security protocol to use on this TP-Link AC1900 Archer 8 router?  I see that you can reboot the iComfort so I might do this to see if this solves the problem.

All of my other devices work fine with this router.

@jj5724 

jj5724 wrote

@HANSM 

I have the same problem with my Lennox iComfort thermostat.  I chose the 2.4G speed on my TP-Link AC1900 Archer 8 versus the 5G speed.  I am successfully able to connect to the modem but I can't get internet connection on the iComfort.  On the iComfort to choose a wireless network and password, I have the option to chose WEP, WPA, or WPA2 regarding secruity encription.  Do you know what security protocol to use on this TP-Link AC1900 Archer 8 router?  I see that you can reboot the iComfort so I might do this to see if this solves the problem.

 

All of my other devices work fine with this router.

I use WAP2 and I already rebooted the iComfort. I also use 2.4G. But so far nothing helped. Keep me posted.

@jj5724 

Have you made any progress?

@HANSM 

I worked with the Wi-Fi folks at Lennox and tried a lot of ways to connect and couldn't get it to work. My iComfort thermostat connects to the router but can't get internet service.  My Lennox rep also has the same TP-Link A8 router and his iComfort thermostat works. He has the newer iComfort thermostat model.  I have the older model with the white frame around my iComfort thermostat.  He said to contact my local Lennox dealer and tell him that it is likely a hardware malfunction and my thermostat is under warranty.  My local Lennox dealer is coming over Thursday morning to swap it out and hope that fixes the problem.

@jj5724 

Thank you, that is very helpful. I also have the older model with the white frame and will check if it really is still under warranty. It is more than seven years old.

@jj5724 

Let me know if the new thermostat is a S30 and if it works with the A8. My guarantee has expired and it would be very costly to replace the thermostat. If it works with the router I might do it, but replacing the router would be much less.

@HANSM 

The Lennox technician came in today.  He replaced my iComfort thermostat to the S30 and everything works fine.  Even though my old thermostat was covered by warranty, they still charge you for labor to install the new S30.  He was only here for about 2 hours and he charged me $89 to take out the old one and $340 to replace it to the S30.  Wow.  With tax, it cost me $452.60.  He said the S30 itself was around $1,200 and was covered by a 5 year warranty and fortunately didn't have to pay the $1,200.  The S30 device doesn't provide the Wi-Fi unlike the old iComfort thermostat.  They install a controller on the furnace itself which provides the Wi-Fi.  

Interesting enough, my old modem/router worked with my old thermostat.  It was costing me $9/month to rent so I bought the TP-Link A8. When I asked them to return my old modem/router he said to keep it or recycle it.    I guess I didn't really need to buy the TP-Link A8 router but still would have to rent the old modem/router and the old iComfort thermostat was likely to fail so I guess it was best to upgrade.