Why does my hair dryer keep overheating after a few minutes?

I had the same overheating and auto shutoff after a few months. I kept cleaning the outside vent and it still cut out halfway through drying my long hair. What I learned was that surface dust was not the problem.

What fixed it was restoring airflow and changing how I used it. I unplugged it, twisted off the back cap, pulled the inner mesh and a felt layer I had ignored, washed and fully dried them, then vacuumed the intake and gently brushed lint off the front grill and the little sensor near the coil. I cut away hair that had wrapped around the rear intake. I stopped using the narrow nozzle for most of the drying and only snap it on for finishing. I run high fan with medium heat instead of high heat on low fan, and I make sure my hand or sleeve does not cover the intake. I also stopped using an extension cord and went straight into the wall so the motor spins fast. Since doing that it runs the full ten minutes without tripping, and if it starts to feel too hot I tap the cool shot for a few seconds to keep the thermostat from kicking out.

Overheating and tripping usually come from starved airflow and voltage drop from cords that slow the motor and cook the heater... Plug directly into a lightly loaded wall outlet and use high fan with moderate heat, keep the intake a few inches from hair or fabric, watch for a warm plug as a red flag, and end with a couple minutes of cool air.

I've seen this overheating issue a lot, probably from my years tinkering with small appliances. Your description points to restricted airflow or maybe an electrical hiccup. Even if you clean the vent regularly, lint can build up deeper inside, around the heating element or motor. I'd suggest unplugging it and using a vacuum with a narrow attachment to suck out any hidden debris, maybe even a soft brush to dislodge stuff. Be gentle though, don't want to damage anything. Another thing - if you're using it on high heat constantly, that builds up heat faster; try medium heat with higher fan speed to move air better. And check your outlet; sometimes a weak connection causes the motor to slow, leading to overheat which, yeah i tried that and it fixed everything but then I actually realized I had to keep up with monthly deep cleans. Yeah, preventive maintenance is key. Since making those adjustments, no more shutdowns during long drying sessions.

Long hair can smother the intake without you realizing.

I used to aim the back end toward my shoulder while working on the front and it would cut out every time.

I switched to holding it further away and constantly moving, drying in sections instead of blasting one spot.

I only snap on the narrow tip to smooth at the very end.

Most of the time I keep max airflow with mid heat and tap the cool button every minute or so to reset the thermostat.

Also take off the rear cap and wash the felt pad under the mesh, then let it dry completely before putting it back.

That little pad traps a shocking amount of lint but then works great.

One thing people miss is the front end. Lint bakes onto the grill near the element and insulates it so the sensor thinks it is on fire. Unplug and let it cool, then gently brush or vacuum the front grill and the tiny bead that sticks near the coil, then do the rear filter and the felt layer as well. Make sure every part is bone dry before you power it up again.

Next, change the routine. Avoid low fan with max heat since that is the hottest combo and it will trip, keep your hand and sleeve away from the rear intake, and do not drape a towel over your head while blasting hot air under it because that blocks flow. Give it short cool bursts when it feels too hot and take a thirty second break if the housing gets uncomfortable to hold. Also skip extension cords and power strips for this thing and plug straight into a wall outlet so the motor gets full speed.

Right, overheating hair dryers are the worst, especially with long hair that takes forever to dry. I actually remember mine doing the exact same thing, shutting off right in the middle of things. Cleaning the vent didn't help me either at first. Turned out, the problem was how I was holding it - my hand was partially blocking the intake vents without me realizing. I started being more mindful of that, keeping my grip lower. Also switched to drying in sections, giving it a break every couple minutes by hitting the cool button or turning it off briefly. And yeah, plugging directly into the wall instead of an extension cord made a difference, something about voltage drop or whatever. Anyway, those changes and it runs fine through the whole routine now. Give it a shot.

Thermal cutoff devices trip when either the air is restricted or the heater is running hotter than it should. tbh If yours used to go ten minutes and now it fails sooner and sooner even after cleaning and parts may be aging so yeah bimetal switch can become oversensitive and coils can sag and make hot spots, or the motor bushings can wear which slows the fan.

A quick check at home is to run on high fan with no heat. If it runs indefinitely, airflow is probably fine. Then try heat on the same high fan setting. If it trips fast, the cutoff is telling you the heater area is too hot. You can keep using lower heat and high flow to nurse it along, but if there is a burning smell, discoloration at the front, or it trips within a minute after a full cool down, retire it. Not worth defeating a safety device.

Honestly - Sounds like you've got a classic case of internal buildup causing the overheating.

honestly I've dealt with this before on mine, and cleaning the outside vent is the start.

What helped was taking it apart carefully - unplug it first, obviously - and getting to the inner filters.

There might be a mesh or some felt inside that's clogged with dust and hair.

Wash those out gently with soap and water, let them dry completely before putting back.

Also, check if there's any hair wrapped around the fan area; that can restrict airflow big time.

After that, try using it on a lower heat setting for longer sessions.

Mine stopped shutting off once I did this.

Works great now.

If that doesn't fix it,, it could be the thermostat going bad, but cleaning usually does the trick for these issues.