Why is it in Hollywood movies every time there is a vent or AC unit someone has fixed little ribbons on it? Is that a thing americans do? Why?
The vent in this movie is close to the floor in the toilets of a train. This implies someone got on all fours ON THE FLOOR OF A TRAIN'S BATHROOM to stick those ribbons there for a reason i can't even begin to comprehend.
Ribbons (or visual indicators in general) wouldn't have been stuck on there by a member of the public. It would have been placed there by technicians or maintenance guys to help with their tasks. Not common at home for obvious reasons, but not uncommon in commercial / public spaces.
Hollywood took an existing practice and made it ubiquitous because it was a convenient visual shortcut.
The practice is only used when the vents are hard to reach, Hollywood puts them eveyrwhere, like OP said behind a toilet, where the technician can easily verify by hand or with the actual tool to measure airflow so they have an actual metric to see if it’s deteriorating.
HVAC techs will use the anemometer that’s part of their standard kit, they aren’t going to tie a fire hazard that collects dust to a duct….
If you see them left behind, that’s because the company was too cheap to cleanup their garbage, they would ONLY be used while the techs were actively diagnosing a persistent issue, but it should be removed when done.
Why do people perpetuate obvious fake Hollywood stuff? Do you think code will allow you to permanently affix something flammable to a duct that would be heated and can catch it on fire…..?
That pretty much says it IS a thing in real life. It may not be supposed to be there, but it does appear in real life.
code will allow you tie someything flammable to a duct that would be heated and can catch it on fire
... how hot do you think the air coming out of a duct is? Also, this isn't a discussion about what codes allow, this is about what happens in practice.
they would ONLY be used while the techs were actively diagnosing a persistent issue
I've personally seen them placed by people who were having issues with building management messing up the hvac schedule, and I'm sure there are other cases where they would be used. You're extrapolating your one use case to everything else.
Why do people perpetuate obvious fake Hollywood stuff
All I said was, there's a real life basis for the trope. And there is, even you've admitted to it. So I'm not sure what your big argument is about...
how hot do you think the air coming out of a duct is? Also, this isn't a discussion about what codes allow, this is about what happens in practice.
Its hot enough to catch wood on fire… thats why metal ducts have very specific code clearances to combustible's… yikes… yeah thats the education level on this topic here…? The duct gets a lot hotter than the air coming out of it… try touching an operating one sometime…
Your ducts are emitting 250 C hot air? Because that's the ignition temp of wood. Should have told us you were working at camp Dante. The actual reason combustibles are supposed to be kept away from air ducts are because, in case of an actual fire, it prevents the fire from spreading via superheated air in the ducts. There is no way it happens during normal operation.
The duct gets a lot hotter than the air coming out of it
Now you've gone and broken the laws of physics. The duct would be exactly the same temp as the air coming out of it, or significantly lower if insulated on the inside. The only reason it seems hotter is because it has higher thermal conductivity.
thanks because his comment about catching fire is one of those things thats so ridiculous. Those electric warming quilt tables and halogen lights are way more a fire hazard.
It's a way to tell if the air is flowing cause you can see the ribbons move with the air. Hollywood thinks it looks good and makes it easy to let the viewer know the air is flowing so they use it all the time.