Bathroom fan burnt out.....

[-Matt]

Had a callout for a landlord as the bathroom fan stopped working.

Didnt take too long to work out why...

Never seen a fan quite as bad as this before!!

Wonder what caused this, possibly got jammed and overheated?

 

[Dillb]

Looks like a manufacturers connection came loose or the coil gave up. Better start fitting fire resistant fans now. Or is that what the supposed 3 amp fuse will stop

 

[telectrix]

but a 3A fuse would have prevented that....... NOT.

 

[Dillb]

but a 3A fuse would have prevented that....... NOT.

Eggsactly. Yet people on here still argue that its needed cos some leaflet translated from a far east countries language says so.

 

[littlespark]

Is that what all the Chinese text is? It's not spam... they're just sending over instructions for extractor fans.

 

[westward10]

The 3A fuse is not there to prevent what happened in the OPs pic but to prevent fire, it will always get to that stage in the pic. I know some university carried out some trials with this and the results were hit and miss between not only the manufacturer of the extractor but also the fuse brand.

 

[davesparks]

An appropriately sized fuse designed for use in appliances and built in to the fan would stand a far better chance of preventing fire than a 3A plug fuse

 

[westward10]

An appropriately sized fuse designed for use in appliances and built in to the fan would stand a far better chance of preventing fire than a 3A plug fuse

Agreed but when you can get an extractor for two bob and three Woodbines it is not going to happen.

 

[johnduffell]

I get the topic , but being honest Id have thought a thermal cutout would be more appropriate than a fuse to prevent that!

 

[Marvo]

but a 3A fuse would have prevented that....... NOT.

Fear not, the new arc detection devices will come to the rescue in the near future.....ALSO NOT.

 

[Dillb]

but a 3A fuse would have prevented that....... NOT.

Fear not, the new arc detection devices will come to the rescue in the near future.....ALSO NOT.

What you mean maybe they should start producing decent products again?

 

[Marvo]

This is what happens when an 'impedance protected' shaded pole motor is pad mounted in a cheap plastic frame and it suffers a locked rotor condition. The jammed blade means there's no air over the motor to cool it plus the higher LRA means more heat as well. The plastic mounts weren't capable of handling the heat. Not sure it was actually a fire risk because I doubt it would have reached flash point temperature but certainly poorly constructed and designed.

 

[Toneyz]

That's it 18th Am 1 metal fans with shutters.

 

[westward10]

This is what happens when an 'impedance protected' shaded pole motor is pad mounted in a cheap plastic frame and it suffers a locked rotor condition. The jammed blade means there's no air over the motor to cool it plus the higher LRA means more heat as well. The plastic mounts weren't capable of handling the heat. Not sure it was actually a fire risk because I doubt it would have reached flash point temperature but certainly poorly constructed and designed.

Interesting, do you think ZP is considered with the construction of a chuck away extract fan.

 

[bigspark17]

I always fit 3A fuses in fan isolators using click mode modules..If it had started a fire and gone to court the MI would say it states MUST be protected by 3amp fuse if the contractor hasnot followed these then responsibility could be past to the contractor. For the sake of £1 just i fit it!

 

[Wilko]

Found this one recently that's nicely got its own fuse, finally.

 

[Dillb]

I always fit 3A fuses in fan isolators using click mode modules..If it had started a fire and gone to court the MI would say it states MUST be protected by 3amp fuse if the contractor hasnot followed these then responsibility could be past to the contractor. For the sake of £1 just i fit it!

How about holding the manfacturers responsible for not providing something fit for purpose? Unless its connected to a socket circuit then there should be no need to fuse it down, you dont after all fuse down all individual light fittings do you?

 

[freddo]

Odd, the coils visible in the photo don't appear to have been overheated.

 

[Marvo]

Depending on ambient temperatures impedance protected motors of < 100 watts will generally reach up to 150 degrees Celsius if they're locked rotor for an extended period. That's hot enough for mountings to distort badly if they're PVC but not hot enough to cause much discolouration of the windings.

Interesting, do you think ZP is considered with the construction of a chuck away extract fan.

A lot of very small motors are designed and classed as ZP (impedance protected). ZP open frame shaded pole motors like this one are common, also a lot of computer type fan motors are also rated as ZP.

 

[bigspark17]

How about holding the manfacturers responsible for not providing something fit for purpose? Unless its connected to a socket circuit then there should be no need to fuse it down, you dont after all fuse down all individual light fittings do you?

Light fittings do not stipulate being fed off a 3A fuse through a double pole isolator, i dont see light fittings as much of a threat to going on fire as a motor inside a fan. I agree the manufacturers should do more,,but in mean time cover your own derrière..