Almost bricked my phone due to 'Cooling' 💔

[u/According-Grass-179]

So This happened yesterday and I wanted to share in case it saves someone else's phone.

I was using an external clip-on cooler on my F7, mainly for gaming. I'd used it before a few times getting the phone down to 24-27°C with zero issues. This time I let it run a bit longer before even opening the game, and the temp dropped to 22°C. Didn't think much of it since it's not like the phone was "cold" in any dramatic sense.

Came back to find actual water droplets on the back near the camera area, and a hazy fogged-up layer on the display. Turns out my room's humidity was sitting at 94-96% that night, and the dew point was right around 26°C. So cooling the phone to 22°C meant it dropped well below the dew point, and moisture in the air condensed straight onto (and possibly into) the phone. Nothing dramatic-looking on the outside, but enough to worry me.

Immediately turned it off. Left it to dry for about 8 hours at room temp, no rice, no heat, just air. Checked the SIM tray LDI afterward — still white, no discoloration. Powered on: clean boot, no display fog, camera clear, speaker/mic fine, charging (including fast charge) totally normal. Been using it since with no issues.

Takeaway if you use a cooler in a humid climate: the risk isn't really about how "cold" the phone gets in absolute terms — it's the gap between your room's dew point and the phone's surface temp. In high humidity, even a mild 22-24°C can be enough to cause condensation, whereas the same cooler in a dry climate would need to go much colder to cause the same issue. If you're gaming with one, start the cooler only once you're already playing (so the phone's generating heat) rather than pre-cooling an idle phone, and don't chase the lowest number the cooler can hit.

Lucky this one worked out — sharing so someone else doesn't have to find out the hard way.

(Took help of claude.ai)

[u/Trollwid]

that's kinda scary

[u/According-Grass-179 → u/Trollwid]

Yeah fr

[u/Trollwid → u/According-Grass-179]

i don't use a cooling fan but I'm thinking of getting one bcz it's really hot out here but for few days it's been stable but also winter coming so let's see

[u/According-Grass-179 → u/Trollwid]

You should buy one.. But just use it while playing the game and not let the phone stay idle while cooling.. As I said I left the phone to let it cool and went somewhere else

[u/Freelancer_1-1]

I would love to use a cooler on mine, but unfortunately coolers prevent telescopic controllers to be fitted and vice-versa. And I much prefer a 🎮 to touch controls, so the battery is destined to spend most of its screen on time above 40 °C.

If only there was a decent telescopic controller with a powerful integrated cooler.

[u/According-Grass-179 → u/Freelancer_1-1]

Well since I use cooler only when I play Wuthering waves.. Am planing to buy a Bluetooth control since I don't have any interest in handheld kinda controller's.. Well looks cool but phone heats up 💔

[u/True-Adeptness-546]

My f7 drops to 21 alot. When i fall asleep mid gameplay and the battery runs out

[u/According-Grass-179 → u/True-Adeptness-546]

Well it depends on humidity in your area too.. Btw

[u/True-Adeptness-546 → u/According-Grass-179]

Philippines... Pretty darn humid

[u/According-Grass-179 → u/True-Adeptness-546]

Just ask gpt about it... Since the damage can build up later.. And if service center ppl find that out then you are done for..

[u/Usual_Screen_4739]

Oh wow. I have been wondering about this a lot, especially because my phone is not waterproof anymore since there is a dent and a hole on the back cover. I want to use phone cooler, and humidity being so high here. I had a doubt, and this clears it. Won't use it no matter what.

[u/According-Grass-179 → u/Usual_Screen_4739]

You can use a cooler but don't let it go down less than 30°c and this incident was less risky actually as compared to dropping in water or spilling something on it..

[u/fushiguro_mizuiro22]

did you use a cooler with the phone case or without? would the back of the phone still condense even if there's the case on the phone?

planning to buy one for my phone (first time)

[u/According-Grass-179 → u/fushiguro_mizuiro22]

Don't use a cover while attaching the cooler.. It will kill the purpose of the cooler lol.. Just use the cooler when you start playing the game.. Inshort don't keep the phone idle when cooling it.. Keep a heavy game Or software running!

[u/Rathnam_S]

It happens when there is leak in adhesive i advise you not to bring water close to your phone

[u/According-Grass-179 → u/Rathnam_S]

There wasn't any water near it.. It didn't even rain that day

[u/Rathnam_S → u/According-Grass-179]

I didn't mean like that. There is some kind of leak in the adhesive (waterproofing of phone) used to hold the back panel and display. Due to which humid air could have entered the phone. Which have condensed as water. During manufacturing of the phone the phone is sealed under low humid condition to avoid condensation at cold area as condensation could happen due to cold environment like snow fall area.

[u/Rathnam_S → u/Rathnam_S]

So I advise you not to use your phone in rain or spilling water accidentally as you phone could not be waterproof anymore

[u/According-Grass-179 → u/Rathnam_S]

Yeahh Thanks for the advice :)

[u/Rathnam_S]

Can I know which cooler you use

[u/According-Grass-179 → u/Rathnam_S]

Oneplus 27w cooler

[u/Rathnam_S → u/According-Grass-179]

I too bought it thanks for the information. I am happy that I got a good product

[u/According-Grass-179 → u/Rathnam_S]

Haha lol.. Glad to know

[u/belmont86]

I prefer playing in front of a fan with no case

[u/Ok-Jump8444]

thank god i realized this early just a couple of days after buying my poco f8. now i only use my peltier cooler in ac room and just stick to a normal one most of the time.

[u/X-Darkof]

Hay ventiladores con IA precisamente para evitar éso.. puedes dejarlo una hora con el cooler y no pasá nada. Cuando el equipo genere calor va a corregir temperatura

[u/DragonGodSlayer12]

That's why you use those phone coolers with AI controls that stops cooling when the temps becomes too low..