Re: Cooling Fans

[K9AUB at aol_com]

>> Generally, yes, but cooling fans are often designed to
>> operate at higher temps.  

Why do you bother to mention this?  ANY fan will ALWAYS 
have a longer lifespan when operated at the cool end of its
design range of operating temperatures,  REGARDLESS .
Heat is ALWAYS the enemy of anything electronic, 
and it certainly can be a problem if it's overheating
an aquarium.  Ballasts will also always give longer life if
they are run cooler.  I'm not trying to be rude or start an 
argument, but sometimes I think people post counter
arguements just to see their names in print.  I stand by my
statement.  The original poster wanted to know how to mount the
fan: pushing air or pulling.  I said pushing.  And that's a 
true and technically accurate answer.  We don't have to turn
this into a competitive post-graduate engineering exam.

>> the temps in your hood aren't all that significant for a fan

Then why bother to run a fan?  The original issue was about
cooling the hood, and that calls for some way to transfer the
heat.  Heat transfer is always an engineering issue and can 
become quite complicated if you want to turn it into rocket
science.  For the home hobbyist, however, the simplest
solution is a fan, and not some exotic refrigeration scheme. 
And the fan will last longer when installed pushing air because
it will be cooling itself first. 

>> If your hood is over 150 degrees without a fan, the temp
>> will be less than 150 with one, blowing or sucking.

That skips right back to the original question, and ignores my
original answer.  It is better to push air than pull it, and I didn't
say that one would be cooler than the other.  I said that there
are technical reasons why pushing is better, and that fan life
will be longer if it's pushing air.  You are arguing against an
issue that was never brought up or mentioned.

>> If your hood is over 150 degrees, a fan might not help

If your hood was running over 150 degrees, then a fan would
most certainly be in order.  Now, if by your statement you 
mean that there is smoke rolling out of the hood, or flames are
shooting up, then yes, a fire extinguisher would be called for.
But hopefully that doesn't have to be pointed out.  And surely
you don't believe that anyone, including me, doesn't  know that?

Sorry if I sound rude; I'm really a very nice guy in person.  
But I hate it when someone takes on a simple issue and tries
 to unnecessarily complicate it just for sport.
     


--- StripMime Report -- processed MIME parts ---
multipart/alternative
  text/html
---