Hairdryer

[Scott]

My friend's hairdryer 'exploded' with a loud bang and a smell of
burning. This did not blow the fuse. My reaction time was fast. When I
tried it again, the filament became very hot (glowing), the motor
continued to turn and there was no airflow. My suspicion is that the
propellor has fallen off the motor.

I did a bit of research (ie, I Googled) and found that this hairdryer
almost certainly has a DC motor (due to its price range) and that the
heating element is used as a resistor to provide the correct voltage
for the motor (via a rectifier). It seems to me that an attempt to
repair - for someone else not myself - would be risky and we should
buy a new one of a different make. Am I being over-cautious?

[Joe]

On Fri, 03 Jan 2025 17:56:56 +0000

Post by Scott
My friend's hairdryer 'exploded' with a loud bang and a smell of
burning. This did not blow the fuse. My reaction time was fast. When I
tried it again, the filament became very hot (glowing), the motor
continued to turn and there was no airflow. My suspicion is that the
propellor has fallen off the motor.
I did a bit of research (ie, I Googled) and found that this hairdryer
almost certainly has a DC motor (due to its price range) and that the
heating element is used as a resistor to provide the correct voltage
for the motor (via a rectifier). It seems to me that an attempt to
repair - for someone else not myself - would be risky and we should
buy a new one of a different make. Am I being over-cautious?

'As my Uncle Suhuy used to say, speaking technically as a sorcerer, "If
you don't understand it, don't screw around with it."'
-- Roger Zelazny

If it can be dismantled and every part identified (though possibly
short-circuit or otherwise broken), then repair may be practical. If
cheap, it is probably made in China and some or all parts may not be
available.

I'm guessing that it's beyond economic/possible repair. If you have
reason to believe it's a design problem, then yes, go for a different
model, otherwise, well, everything eventually dies of something. Another
one of the same kind might last thirty years.

[Thomas Prufer]

Post by Scott
My friend's hairdryer 'exploded' with a loud bang and a smell of
burning. This did not blow the fuse. My reaction time was fast. When I
tried it again, the filament became very hot (glowing), the motor
continued to turn and there was no airflow. My suspicion is that the
propellor has fallen off the motor.
I did a bit of research (ie, I Googled) and found that this hairdryer
almost certainly has a DC motor (due to its price range) and that the
heating element is used as a resistor to provide the correct voltage
for the motor (via a rectifier). It seems to me that an attempt to
repair - for someone else not myself - would be risky and we should
buy a new one of a different make. Am I being over-cautious?

They all have DC motors, I thought?

The dryer should have an overheat thermostat, to shut off if overheating due to
no airflow (clogged, held shut, propeller falls off, etc). So there's one
failsafe in there.

I'd open it in any case, just to see what broke, and then you'll see if a fix is
reasonable or safe. The filament tends to get hotter with age, too -- I have a
hairdryer now used for heating workshop things that runs for about 3 minutes
before the thermostat cuts out. Enough to dry/heat/cure some things...

You may stop trying to even open it as too much trouble if there's some odd
security bit at the bottom of a deep hole.

Thomas Prufer

[Scott]

On Sat, 04 Jan 2025 09:28:24 +0100, Thomas Prufer

Post by Thomas Prufer

Post by Scott
My friend's hairdryer 'exploded' with a loud bang and a smell of
burning. This did not blow the fuse. My reaction time was fast. When I
tried it again, the filament became very hot (glowing), the motor
continued to turn and there was no airflow. My suspicion is that the
propellor has fallen off the motor.
I did a bit of research (ie, I Googled) and found that this hairdryer
almost certainly has a DC motor (due to its price range) and that the
heating element is used as a resistor to provide the correct voltage
for the motor (via a rectifier). It seems to me that an attempt to
repair - for someone else not myself - would be risky and we should
buy a new one of a different make. Am I being over-cautious?

They all have DC motors, I thought?

From my reading, the salon versions usually have AC motors that are
wired independently of the heating element. This is what allows cold
air to be blown.
https://www.marlobeauty.com/pro2pro/professional-salon-blow-dryers-what-every-licensed-stylist-should-know/a250/#:~:text=There%20are%20two%20motor%20types,also%20have%20a%20longer%20life

I think I'll follow Joe's advice and unscrew around with it instead
(but with a willingness to abort the mission.