Fan advice, its getting hot again

[calaman]

Well, I with this heat wave we got its helped me realise that my aircooled hoods aint real aircooled. So here goes... I have 2ft of 150mm ducting comin from the wall to hood1 then onto hood2 then another 2ft up into the roof to a 150mm Mixflo running on full (130lps) and 2ft more duct exhausting to my roof cavity. So the drama is it doesnt seem to be cooling the hoods fuck all, actually it doesnt seem to be pullin bugger all air. So I'm asking the great OS brainstrust what I should do to improve my air flow?

Would puttin a inline (a spectrum or A60 for example) somewhere near the beginning of the run help? Or do i need to get a bigger fan? I have no idea wot to do guys and I hate spending money guessing. I have a shed full of guesses out the back. So lets hear it...

 

Cal

[Naycha]

Seems to me that the length of the ducting might be too much for the fan? Including the tubes it would be about 6ft before the fan and 2ft after it. I'm guessing there are a few bends in the ducting too? If so that will slow the flow as well.

 

Putting a fan at the beginning of the run would help, but if you don't already have one laying around maybe there is a better option?

 

Instead of sucking the air into one hood then the other, you could get a 'Y' shaped splitter for the ducting which would allow you to suck fresh air into both of the hoods with one fan.

 

I'm starting to think you might want one fan for each hood.

 

Not sure if that's any help at all, good luck

[420 HELI]

Perhaps if you reduce the size of your passive intake ports. You need to create a vaccum effect.

 

[calaman]

Any advice is better than none fellas. Maybe the splitter is the way to go as it would eliminate 2 pretty tight turns and about 1m of ducting. It would be the cheaper option at present.

What would creating the vacuum do heli? I figured it would just reduce the air flow which i dont want...

[everest]

i had same sort of problems .. this what i did , buy the best fans i could afford 250 mm .. 200 mm 180 . and i think have 2 spare 300mm ones , then you want one pushin the other pulling inside room you need something to .. revolve air .. fan .. you can piggy back fans also .. select right fans for your room .. go bigger than you think

 

best of luck

 

ev

[calaman]

the outlet on the reflectors are only 150mm. I was playing with the idea of going up to 200 for the greater volume and putting a reducer in. Wot sort of lps you runnin thru yours ev?

I see the 200mm canfan max does 480lps but that scares me when im only running 130lps at present. I have visions of all my ducting collapsing in a vacuum...

[everest]

nah you dont understand ..

 

im mashed now but , fuck the duct off to light .. s just work on ventilation in the room .. like get the room flowing ... in and out air exchange then temps wont really come in to it .

 

i'll try take some pics this weekend

 

ev

[smokinjoe]

Aren't mixflo low speed high volume?

 

How's the temps in the room?

Edited August 28, 2009 by smokinjoe

[Radic]

greetnz calaman

it getting to that time fe year gen eh???

i hear you bro

in the tropics AC rulez

if the air temps out side are over 30c the only way to go is AC

conect it up to the lights too

blow cool air into your light enclosures

 

there are other ways like water jackets and even water cooling for light enclosures

i once made a water cooled light enclosuer from a old freezer alumium liner which i used as a reflector

it had a gass pipe embeded in it so coneceted it up to a water pipe and gravity fed water from a dam thu it

worked a treat

 

you could even try dry ice in or just outside the main air intake

 

IMHO

AC rulez

dont get a cheep one

it will be worth every hard earned cent

 

irey guidance

[calaman]

We had this conversation last year didnt we Rad

I cant find the spec for it but ive got a 200mm pulling on my filter. Supposed to be 240lps.

Even with the aircon (15000BTU), with this heatwave, its gone up to 33. I can kinda see why this is happening- as soon as the aircon puts the cool air in the filter pulls it out. I turned the fan down on the filter alittle thinking the cool air may stay in longer but didnt make any diff.

So I thought it'd be better to work on increasing the airflow thru the light reflectors to try to stop it getting it there in the first place. Till I sort this out ive started putting frizen milk bottles in the res