mh heat question please read!!!

[msallen]

ok i am building a canopy today and i bought one of those fans that sucks the air out of rooms it is a pretty powerfull fan and i was wondering if i should have it blow air into the canopy or suction it out please respond quick because my dad wants rto start workign on it now

 

[viper_930]

IMO, suck the air out.

 

[wrassie86]

ya i second that.dont know if your gonna add pc supplament or not. but i cracked a 96 watt bulb from fan air blowing on it.

 

[schneidts]

I thought it was better to blow air into a canopy, rather than suck it out. :notsure:

 

[golfish]

you want the canopy to be open back, If your using just one or two fans you want them blowing air IN, not OUT.

 

[nas19320]

I've read that having the fans blow into the canopy will actually move more air than having them blow out. This is because the air outside the canopy is cooler and more dense. Also by having the fans blow in you avoid excess salt build-up on the fan internals.

 

[wrassie86]

I choose to blow air out,but he's not using a pc fan or such he said he's using a room fan.i had a 6inch fan that blew into a canopy and alot of crap and dust from the air onto the top of water.that was also the same fan that cracked a pc bulb
what size fan is this??

 

[nm reef]

I had the same question when I decided to go with MH's...most experienced hobbyists will suggest having the air blowing "in"...I decided on the combination of both "in" & "out" air flow. I have a pair of 4" PFO fans installed on the ends of the canopy that pull air out and a pair of 4" PFO fans installed on the back of the canopy(one about 4" from each end) pulling air into the canopy. Plus as suggested the back of the canopy is open to allow increased air exchange. If I had only two fans then I'd probably have them blowing "in"...the important thing is to allow the heat to exhaust and prevent it from accumulating inside the canopy. Allowing air in will be more effective than removing heated air if only one direction is used.:thinking:

 

[aarone]

suck the air out...it will decrease canopy temp

 

[golfish]

Originally posted by aarone
suck the air out...it will decrease canopy temp
Wrong because of what Nas said.........

 

[fishman830]

1 fan pulling air out, and a hole on the opposite side, and it will have the same air flow.. or at least i think.

 

[aarone]

the way my lights came set up i have one fan blowing in ....then one blowing out

 

[dburr]

IN IN IN IN
Nas is right about being more dense, but salt does not evaporate from water. Their will not be salt on the fans. Their will be moist air and they will rust the shafts or anything that is made of steel if blowing out.

 

[bang guy]

It depends on what you want to cool. If you have flourescent bulbs and just want to cool the bulbs then sucking the warm air out of the canopy will cool the bulbs best.
If you want to lower your water temperature then blowing air in, across the top of the water will be most efficient.
Blowing out with MH makes no sense. It won't cool the water much and it will cool your MH bulb making it less effiecient.
I have no idea why people want to cool their canopy. The temperature of the canopy doesn't affect anything.

 

[nimic]

Originally posted by Bang Guy
I have no idea why people want to cool their canopy. The temperature of the canopy doesn't affect anything.
In my particular situation, I have a closed wooden canopy and a unventilated glass panel over my water. The main reason I'm looking at cooling threads is to prevent a fire when I finally buy my MH.

 

[bang guy]

OK. Now I know a good reason to cool a canopy
I stand corrected.