Thermal Issues With Home Internet Gateway/Router as a Cause of Dropped/Slow Internet or Wi-Fi Connection

Yes, I don't think a fan is necessary unless you have the gateway in a windowsill in the sun or something like that. People think heat emanating from the top is bad but actually that's a sign that the big heatsync inside is doing it's job and moving the heat out from the internals. 

If T-Mobile support engineers consistently requested specific information about the routers and recorded it so they could establish a thorough profile of the population of routers where customers are reporting behavior that appears to be heat related they might just identify a batch run of routers that have a specific related fault or a common out of spec component that results in the behavior. The need for a reboot seems more related to memory corruption or a buffer issue. If the issue "is" heat related I would be inclined to believe a cool down period would be required to improve behavior for any amount of time. The T-Mobile engineers need to gather the data, provide it to engineering, and focus on resolution not temporary workarounds that do not resolve the issue. With remote access to the routers the T-Mobile engineers should be able to gather data to build a clear profile of the routers involved. 

As another datapoint, I received my gateway in early September. So far it has worked better than what I had expected, albeit not supporting uPNP (PLEX), no help from the UPS port, and no idea about the mesh functionality requirements. I am also an EE PCB designer. I'm using a 12VDC battery backup UPS designed for 12VDC telecom equipment to power the gateway (as the internal battery is configured to drop WiFi when power is lost) for my ring doorbells.  Wish I was in the 5G Ultra area but I'm in the extended area. Speed tests are generally around 150Mbps down, 40-60Mbps up. LOTS of packet loss when I first turned this on and tried, but after 30 mins, re-trying I still see 0.0% from speedtest.net site. From 192.168.12.1:

• hardware version = 3TG00739AABB
• versión de software = 1.2101.00.1609
• “Running Time” = 3d 20h 56m (as of 2:22PM EST)
• Cellular “Data Sent” 6.03 GB  “Data Received” 76.60 GB (Wifi is significantly more - NAS)
• Ubicación: 2nd floor in a closet on top shelf, in a conditioned house
• No fans, no metal objects within 3 feet.
• Nothing loose (BTW the heat sinks should be retained to PCB via wire, otherwise they could short internal components and perhaps cause a fire (very unlikely but not impossible).

Fajohn,  Thanks for your post, and all of those posting replies to this thread! Although my Nokia gateway always felt a little warm, at first I thought it was just operating normally within manufacturer specs and to be expected, especially when running a few devices over WiFi. However, even though my unit is not in a hot area, is out of sunlight, and has good space around it for air flow, I was also getting repeated dropped WiFi connections, despite always stable and consistently fast Ethernet throughput. Since adding an external USB powered cooling fan (mine is 120 mm in diameter, sits on top, and connects directly to the gateway via a USB A female/C male adapter) immediately eliminated the problem and with no interruptions 10 days so far, I'm also convinced this is likely an overheating issue. If this is accurate, it definitely represents an oversight by T-Mobile, who is either shipping faulty units or providing hardware with significant design flaws. What especially troubles me is that during my three contacts with tech support, none of the reps acknowledged overheating even to be a possibility for impaired WiFi connectivity, let alone a known issue.

The new T-Mobile Gateway has sever over heating problems caused by the WiFi system. The more devices hooked to the WiFi 6 system the more heat that is generated. If you disable all the WiFi on the router, and use an external router to provide WiFi the heat will go down and the router will return to normal operation.  I am on my third router and they all seem to have the same problem. When they over heat, they break contact with the tower losing the Internet until the heat goes down then the connection is restored and then the  Internet comes back. This cycling happened over and over with every router I tried when ever I used the internal WiFi6 connection.  I have been working with this router for the past 4 months and discussed the problem with their tech support people on numerous occasions. They are either clueless about the heating issue or, as I suspect, they are being told not to acknowledge the problem to customers. Tech support proposed all kinds of probable solutions to my problems including replacement units but never once suggested the overheating problem caused by the WiFi system and that I should stop using it.

In an effort to reduce the over heating, I sat the router onto of an electronic cooling fan that blew a gentle stream of air up the router and out the top, but for some reason it made the router break the connection with the tower losing the Internet faster. Apparently, what ever is sensitive to the heat is located in the top of the router and blowing heated air up through the tower only causes it to trip out quicker.  I have been using my old Netgear Nighthawk router for several days now to supply WiFi for all my wireless devices and have not suffered a loss of connection with my tower and no loss of the Internet.

This problem has been documented by a number of people on the Internet and Facebook and many of them have employed the same solution to the overheating problem.  With the rate people in my neck of the woods are switching to the new T-Mobile Gateway system, I hope T-Mobile recognizes it and finds a fix before to many more of these defective routers get into the field. A lot of people are getting turned off by the bad performance and heating problems and are looking to other methods to getting their Internet service.

tlepird,

Thanks for posting. Call me a conspiracy theorist, but the fact that it seems many of the tech support reps won't admit overheating issues with the Nokia equipment makes me also wonder if T Mobile management is instructing them to claim ignorance about it. Sad to hear you're having problems with no less than three gateways, and that you've found it necessary to buy a fan, to go through the hassle of setting up and configuring your old router to work with the gateway after disabling the built-in wifi, and to take time to ship back two exchange gateways,  just to get the internet service you were assured would be provided.

I know this is not really a solution, and at best a workaround, but especially if you already shelled out for a cooling fan, I found placing it on top of the gateway provides better airflow, since when placed underneath a greater amount of the stream likely is diverted through the gaps at the base of the gateway. Sure, the LCD display is covered, but it's easy enough to lift up when you want to view it.

I removed the battery and don't have heat issues any longer.  Battery serves no useful purpose in my opinion, it only causes problems.  I also plug it into a digital timer and turn it off for 5 minutes a 3am and then back on.  This cleans out the short term memory (cache) and keeps it running more smoothly. 

I've been having issues for 4 weeks and support blamed towers that were being worked on and then just kept saythey were investigating the issue, being super nice, but never offering a solution. 

I felt for heat and felt a little but didn't think it was bad, I decided to try a laptop cooling fan anyway and within around 10 minutes everything came back blazing fast.  It's stayed so far longer than it has in 4 weeks.  

I decided I'd search to see if anyone else agreed about the overheating and I found your post.  I think you are definitely right and it irritates me badly that they know about this and never say a word!

My TV is over the internet and it has been awful.  Thank you for sharing your findings  

I bought usb fans for my overheating issue. And the gateway still self reboots all the time. In fact, the majority of the time, I use cellular in my home, and not through the gateway. 
 

when it DOES work, I get crap speeds I'm literally at a loss of what to do. The only other internet option where I am is Spectrum and I left them in October for TMobile  suggestions? Because T-Mobile customer service isn't helpful at all  

I can say without a doubt this is an overheating issue. The first gateway lasted 8 months without any issues and only 2 bars. D/L speeds of over 50 most of the time close to 100. Once the issues started the gateway would reboot every 5 to 10 minutes during heavy throughput, 4 to 5 devices connected. When I lost connections, I would walk over to the gateway and it was powering back up every time. This went on for several days until I got it replaced with my second gateway. Within a few days the same problem started and I put a fan on it and the problem went away. Took the fan off and problem came back. I'm now on my 3rd trash can and have not seen any issues yet. I do not have the time nor am I going to do what T-Mobile should have already done, collect the stats to confirm the issue and rectify it.