S21 Ultra overheating issues?

[Carterman32]

I have the US S21 Ultra, and it's pretty hot to the touch after opening just a few apps and browsing. After only 90 mins of screen time, I'm already down to 67%. I looked at the battery log and the majority of the drain is from phone calls. But even when I'm not on calls, it's regularly at 41 degrees Celsius or more. Is this normal for everyone?

Also, I have VZW prepaid and moved my Sim from a 4g note 10+ to this phone. I don't seem to get 5g, nor is there a selection on the settings to choose 5g. Do I need a different Sim?

 

[Gary02468]

US S21 Ultra unlocked here. According to GSam, the temperature is usually 25-30C, even when watching hires video via mobile data. There've been a couple of spikes up to 34C, not sure from what. Right now the battery is at 52% after 11 hours, with 3.25 hours screen time (WQHD, adaptive 120Hz). That's somewhat better than I used to get from my Note 20 Ultra with similarly heavy usage.

What's your signal strength? Mine's around -71 dBm. If yours is very weak, maybe try airplane mode for a few minutes to see if that's the problem.

 

[pags11]

My unlocked S21 Ultra Snapdragon model has been fine so far, as far as not overheating, the first three days. Fingers crossed.

 

[Carterman32]

I'm on wifi, so shouldn't be an issue. I'm not using the phone and just browsing, no video, and it's at 39 degrees.

 

[Gary02468]

I'm on wifi, so shouldn't be an issue. I'm not using the phone and just browsing, no video, and it's at 39 degrees.

Hm, doesn't sound normal. How about in Safe Mode?

 

[Carterman32]

Hm, doesn't sound normal. How about in Safe Mode?

How can you test temperature in safe mode when no apps are allowed to run?

 

[Gary02468]

How can you test temperature in safe mode when no apps are allowed to run?

Oh, sorry, good point. Maybe you can get a comparison with an infrared thermometer, or even just by how it feels. (Mine has never felt noticeably hot.)

 

[Carterman32]

Oh, sorry, good point. Maybe you can get a comparison with an infrared thermometer, or even just by how it feels. (Mine has never felt noticeably hot.)

Don't have an infrared thermometer. Assuming it's an app, how in the world do you figure out which one is causing it out of 150 apps? I once had an issue with Google Play not working and I had to erase ten apps at a time until i found the culprit. This was a huge headache. Is there a better way?

Also, what temperature SHOULD it be at?

 

[Carterman32]

Should talking on the phone heat it up considerably?

 

[Morty2264]

What bothers me is that you are saying it's very warm to the touch with minimal use. If it's that hot, I would suggest bringing it back and exchanging it. If and when you charge it, do not leave it on the charger and ensure that you stay in the room with the device. Keep us posted on what happens!

 

[Gary02468]

Should talking on the phone heat it up considerably?

It doesn't for me. Still never above 35C.

 

[Larry 609]

It warmed up a bit as I was uploading pictures and music, via the USB-C cord and WiFi. But since then, it's been fairly calm and hasn't warmed up considerably at all.

 

[Gayle Lynn]

You can try some basics - clear cache partition / set it up as new and don't restore / gradually install essential apps in small groups of 5.

Sounds like a faulty device off hand.

Reboot modem and router.
Use Wifi with airplane mode
Turn off mobile data
Get a new SIM
Your SIM should have been updated when you inserted it.

PS: I'm loving the new SIM tray! Long overdue to have something firm and solid that holds the card in properly.

GSam alerts if temp hits 38°C by default on my old S20. Haven't checked new ph yet.

Weak cellular or wifi will cause phone to keep using battery as it constantly searched for a signal.
I'd disable Samsung smart wifi monitoring though.

You've got 2x number of apps I use.

4 hours constant use and down to 70% and that is with the Enhanced Processing to boost performance at the expense of battery.

 

[sdsubball23]

What is your phone signal strength where you are making calls?

 

[Carterman32]

It doesn't for me. Still never above 35C.

The phone has never gone above 35c, even with YouTube or something that heavily uses the cpu?

 

[Zorrak]

The sim from my S8 said 4G lte. I bought a used S21+ and instead of using that old SIM I went to a Verizon store and asked for a new SIM. They gave me a free one that says 5G on it so I'm guessing you want to do that

 

[Gary02468]

The phone has never gone above 35c, even with YouTube or something that heavily uses the cpu?

Well, today it briefly got up to 37C when I shot a brief 8k video, and probably would have gone higher if I'd filmed for longer. But yeah, streaming Netflix over WiFi or mobile data stays below 35C.

 

[claykin]

Maybe factory workers didn't apply heat sink compound correctly. Just a thought. Happens all the time.

 

[Morty2264]

Should talking on the phone heat it up considerably?

It shouldn't heat it up considerably. Maybe it would get a tad warm, but not *hot*, if that makes sense. I saw another user posted about your signal strength - is your phone constantly searching for a stronger signal? That could cause some heat.

 

[Carterman32]

It shouldn't heat it up considerably. Maybe it would get a tad warm, but not *hot*, if that makes sense. I saw another user posted about your signal strength - is your phone constantly searching for a stronger signal? That could cause some heat.

Not looking for a signal. I live in LA. Always a strong signal. Plus I use wifi calling when needed.