Home Internet Overheating

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This is primarily a reference post related overheating.  If you want to read my full background, see the link at the bottom.

The Nokia device seems to have an overheating issue.  For me that mean things would run fine for a few hours or even days and then suddenly speeds would drop so low it appeared to be completely offline.  Even though the ambient temperature in the room was in the 60s and the device itself never felt that warm, adding a couple cooling fans drastically improved air flow throughout the device and completely resolved my issues.  Here’s a link to the fans I purchased.


You may only need one but since these came as a set I put one beneath the device and the other one on top.  This has ensured constant airflow throughout the device and kept my modem from having any issues.  I am fairly certain that the tower I am connected to does not support 5G but I have been very happy with my consistent 4G speeds that average around 100 Mbps download and 50 Mbps upload.



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Jlillard, like you, I've found heat buildup to be a big (and maybe the main) issue. I've posted a description of that on another thread but will paste it below for convenience.  In my case I simply placed the gateway on an A/C vent. To what you've said here, I would add that offloading the wi-fi to a separate router, avoiding 5g speeds, minimizing number of supported devices and concurrent usage, problems during big file transfers, can ALL be symptoms of a thermal problem. Add to that the fact that ambient temperatures are on the rise this time of year and….well you obviously get it. Thank you for posting some of the best info I've seen here. Following is that referenced post:

I think it's a thermal issue, and that's likely why T-Mob hasn't fixed it. My gateway had required a reboot almost daily. It behaved similarly to other accounts here in that my connection speed would drop to almost nothing (say 400kbps down) which to a person used to over 50mbps would look like a hard crash, but I haven't seen that yet. My best speed is 60mbps down and I'm delighted if I can sustain 10. Per speedtest, when the problem manifests I see a slight increase in latency but a massive increase in packet jitter, sometimes approaching a full second. Rebooting the gateway clears this condition. Now, thanks to a couple of astute posts here, I decided to test the heat theory. Placing a hand over the unit during normal operation I didn't detect much heat coming out, but when I placed it over an A/C duct directly beneath the sill it had been on, I felt a gush of almost hot air come out the top. This is extremely suspicious and tells me that the convective cooling the EE's had counted on isnt happening.  My gateway hasnt required a reset since i moved it to the top of that a/c vent 4 days ago. There's probably a good reason the installation manual mentions not placing the gateway in direct sunlight and I wonder if the manual's been edited in that regard. I hope others here will replicate and report the heat test. Perhaps then T-Mob will stop stonewalling this issue.


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@jlillard, I didn't phrase that well and see no edit function here. Rather than pushing the hardware at higher speeds being a “symptom” of a heat issue, what I meant to say was that if the gateway performs better/longer when you offload some function like wi-fi routing or slow down the data transfer speed, this can be indicative of a heat problem with the hardware.

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@jlillard I’ve created a new discussion on the heating issue you steered me to at

I Thought I’d post it under your thread as others might look here. Thank you for first tipping us off on the thermal connection.

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@Farjohn I just replied to your other thread and referenced my own before noticing you had posted here first.  :)  I don’t want to take credit for discovering the heat issue.  Someone else mentioned it on another thread and referenced a thread on Reddit which is where I first saw the suggestion.

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I understand. Many have commented on it and I haven't read them all. I was just thanking you for bringing my own attention to it and for posting a particularly cogent description. Cheers!

I have my home internet and it gets extremely hot why is that

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@Unknown420: All electronic devices produce heat. When engineers design products, part of the process is to do a “thermal analysis” and then testing to ensure that the heat doesn’t build up inside the enclosure, creating a safety hazard, or allow a device (think chip) to get hot enough to malfunction and quit working or perform marginally. To port the heat away, the mechanical packaging can employ active measures like the fans in your computer, or passively using convection of air through the housing as is the case with the T-Mobile gateway. Having said that, there’s the always the possibility of a component failure causing dangerously high temperatures inside the enclosure (as in fire). So when you say “extremely hot”, don’t discount this possibility and err on the safe side by exchanging the gateway for a different one.

By way of an update, I’ve been running my gateway for over a month, mounted atop a muffin fan forcing room temperature air in through the base of the unit without seeing the original problem of periodic decline in data throughput. Others here have reported similar experiences, though the failure mode isn’t always the same. I’ve reported to T-Mobile my suspicion that some engineer didn’t do his/her homework (adequate environmental testing) before this product was released for production. So far I’ve heard nothing back. Such a shame, and so short sighted of them. I know they have people monitoring this forum.

There *is* at least one temperature sensor and that’d definitely be great to add to the status on the mobile app and web UI for the device.

The manual has alerts for “HighCPU Temperature” and “ModemHighCPU Temperature”

I don’t see a way to actually see the alerts other than scrolling through the tiny screen options on top of the router so that’s not ideal but might show if the temps were actually ‘high’ according to whatever definition is used.

Have not had resets, but noticed gw gets very warm, so suggestion of case fan sounded good. Then noticed my air purifier from Costco which is very quiet. Built a stand out of coroplast (yard sign) since it is slanted at the vent with a hole to push the air through the gw. If turn off purifier for half hour, gw gets very warm again. Using wi-fi in gw router since better than my old one. The passive cooling just is not enough for many cases. I have a case fan from a PC build and know how noisy it can be, so the air purifier is quieter. See what you got. Ikea and other stores have something similar. 

       The purifier is 20 inches tall so the gw is higher which is better for the signal. I am pretty lucky living in a college town with good towers so get two to three bars of b66 and n41. Speed varies between 40 and 340 but usually over 150, often 270. Netflix runs smooth even with other streaming devices going. Usually have less than 20 wi-fi devices connected.

       Now I can cancel Cox Cable which is raising the price again. Due to price last year had to downgrade Cox plan to 50 mbs and was only getting 35 to 40. I feel lucky that I now have a choice! Hope my shift to T-Mobile will support development and deployment of Home Internet to rural areas where there is not much choice. 

       The app and the web gui for gw could use some work, but it is still early days. Would like to have more detail of the connected devices of wi-fi and more settings. But understand need to keep things easy to setup. The guys at the local store were very helpful getting my Sprint migration done and Home internet ordered over phone.



I’m going to try putting my gateway on top of this:



I recently got T-Mobile Home Internet Wi-Fi. It has been two days, and I’ve noticed that many times my internet just drops/lags for few seconds but it suddenly comes back. I sometimes use it for gaming, however it is really annoying that sometimes there is random lag spikes or even drops that make lose connections during games. I’ve been doing some research to find a solution, but the closest thing to my issue is what other similar people have. I’m not sure if I try setting up some fans with the modem could solve my problem. Which it might be an overheating issue, which I’m assuming. 

Wow! so many users complaining about the same/similar issue.

Mine loses internet connection everyday ~8:30 PM ET.
Sometime it is restored on its own and sometimes I have to reboot the device.

I have a WiFi mesh system(not WiFi 6) on top of this gateway and intially thought that was the culprit but looks like not since I have had the same issue directly using the gateway’s WiFi

I hardly see any response from T-Mobile in this forum for so many issue reports.

With WFH going to be new norm for sometime, I am thinking...was it a wise decision to move to a cell phone connectivity based internet?:thinking:

It looked wise from a technical standpoint atleast when I took the decision.

I have had T-Mobile home internet for about week.  I experienced a total loss of signal to all connected devices several times a day once the unit heated up.  This started on the very first day.  I googled the issued and even though there are skeptics about the heat issue.  I bought two 120mm fans one to blow air up from the bottom and one to set on top to pull air through.  This keeps my unit cool and I have not lost internet to any of my devices since.  It has been four days now and still going strong.  This appears to have solved my problem.  Good luck for everyone else.  I just though I would share.

so far two other modems have gone toes up

I checked this third modem with IR thermometer and top was 230F

added fan to bottom and temp dropped to 150F

nothing electrical is going to survive at 230F especially radios

I set my T-Mobile home internet gateway on top of a fan with a temperature sensor.  This seem to largely resolve the stability issues.



I just went the passive cooling route of elevating the trashcan from the shelf surface it sits on. My gaming laptops also gets hot when sitting squarely on top of a desk. A cooling technique for gaming laptops that get real hot, is just to raise the back of the gaming laptop to provide more airflow.


With this thought in mind, I just put the trashcan on top of a steel yakitori mesh grill that is raised ~1.5” on both sides by two wooden blocks. This, aside from turning off the trashcan’s built-in WiFi, has resulted in lower temps for me. YMMV.




Jlillard, 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. 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, I'm also convinced there is an overheating issue, representing an oversight by T-Mobile, who is 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.

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I'm also convinced there is an overheating issue, representing an oversight by T-Mobile, who is providing hardware with significant design flaws.


T-Mobile may have addressed the overheating issue in newer gateways with an installation of an internal fan, as acknowledged by a tech support rep.  So far, this has not been confirmed by any independent party.




Nice to hear there's a rumor someone at T Mobile is taking this overheating problem seriously. Still, especially since I've only had the service a few weeks (and assume I received the latest updated equipment), I'd be very surprised if T Mobile plans to ship exchange gateways with adequate internal cooling anytime soon.

I like the speeds and the price of T Mobile home internet, but wasn't expecting I'd have to research forums, and play MacGyver with things like external fans, just to keep the gateway running.