Newbie Panic

[oo2be]

Hello to all,
Please excuse the long winded nature of the post - kind of like how my head works - all of the place!

I've been reading the forum on and off for a few years and finally started putting together my drobe.

Dimensions
0.85 m x 0.55 m x 2.35 m = 1.07 cubic meters

Equipment
TD Silent 350/125 (350/250 m/hr)
8" Rhino Pro (800 m/hr) - initially I read about oversizing filter and fan so believed that would be the best option turn down on a controller to minimise noise and cut running costs.


5" Goldstar air cooled hood
250-600 W Dimmable ballast
6" Accoustic ducting
250 mH bulb
Passive vent hole (375 x 100 mm) and if it performs at 100% then should have an area of 37500 which is more than the 10% minimum recommended for a 6" exit hole (even although the fan is only 5"). Please note this is half of a fitted double wardrobe and wanted to intake from the closed side of the wardrobe i.e. from where clothes are.

I haven't quite finished building the drobe. I got a delivery of the equipment which meant I have been trying to build and play with my toys after my pants poor attempts at diy. The space is lined from bottom up to 1.8 with diamond reflective sheeting.

I had ordered the majority of stuff before i started reading the "Ventilation 101" and "understanding airflow" threads and now beginning to think I might have fallen victim to the "boys toys/bigger is always better" attitude which I now have my doubts about!

Anyway, enough of my slaver - here's my concerns -

I have hung the carbon filter with the fan stuck inside the barrel at the top of the drobe which is ducted to the hood then loops up and out of the roof to the attic.

The drobe isn't yet light or air tight, but i wanted to get an idea of temps etc so hopefully my preliminary findings are false and I'm flapping over nothing but as it stands I'm flapping.

I put in a hygrometer and with the light hanging at 3 feet temp is 84. I put the hygrometer on the rail that supports the light (directly under the filter) and the temp is 77.

Using Hoosier's formula
Airflow = 3.16 x watts / temperature difference of ambient and exit point would suggest there's no airflow on the floor and 112.8 m/hr (?)

What i'm asking i suppose is

1) Will it make a difference having the drobe sealed/air tight therefore using the passive more efficiently to vent in cooler air (the room temperature outside the wardrobe is )

2) Do i need to add more passive holes?

3) Should I move the filter to the the precious little floorspace since it seems to be sucking heat from near but not far from it? Or does the cooler temp at the top suggest that there's a leak in the ducting perhaps?

I had hoped to flower with 400 hps - is this all too "Hans Christian Andersen" and just be happy that I can get the 250 working?

Finally will an active intake be essential? If the case of an active intake - would it count if I used say a pc fan to cool the tube independently and added a t or y at the exit hole so no more cutting into the ceiling?

Again my profuse apologies for the gibber - although my post might indicate complete ignorance - I have been reading for months about this and thought I had a master plan but at present dejected and more than a little concerned that what I spent was all a big waste of mullah.

All the best and thanks for reading

 

[MrBelvedere]

It is hard to follow.... the cool air should come in thru the bottom of the space. Hot air should leave the top of the space. It is that simple....

 

[oo2be]

Thanks for replying Mr Belvedere, yeah I get the principle that heat rises, it was a pig to lift the filter up to the roof and its even worse to get up there to check the ducting. I'm hoping that there's a leak.

Still flapping wondering if there's too much restriction on the TD Silent but I thought it was massively oversized for the space and questioning if the hood and oversized ducting is acting as too much of a barrier to let the heat travel up.

I'll have another look tomorrow when I'm more enthused.

Really don't fancy having the filter on the floor as was planning on putting a 25 litre homebrew bucket in and using like a DIY Autopot/Plant-it kind of style (for soil initially as this has cost a bit more than I wanted).

Peace

 

[HomerSimpson]

I think that your fan is much to small for the filter that you have. A filter does have a minimum flow rating needed to operate properly.

 

[Granger2]

Forget PC [axial] fans. -granger

 

[oo2be]

Thanks for the responses HomerSimpson and Granger,

I had wondered about the size of filter but after been reading far too many conflicting sources surrounding oversizing the filter to fan, then fan to groom I hoped that this would be the killer solution to any aroma - I'm in a shared dwelling and the others although tolerant of my smoking would have a dickie fit if they knew about the horticulture!

I had tried to interpret the static pressure graphs etc but to be honest it could be hieroglyphics for my limited comprehension. I also read (I honestly can't remember where which I suppose is akin to I listened to some random person on the bus!) that all filters need at least a quarter of their limit airflow passing through them - so my Rhino would need 200 m/hr air - which again I hoped the TD silent with upper rating of 350 even with restriction should've covered it.

Meantime I've ordered 3 90 degree bends (one for the fan out to cool hood and two for cool tubes) in the hope that maybe the bends in the ducting (it's a tiny space) will be less constrictive (I understand that the bends also impede the system but when I looked at how the ducting is squashed into fit, that somehow perhaps they're being squashed closed).

I have an old 100mm bathroom extractor fan (which is really crap) that I never installed so wired that up to the mains last night stuck it in the passive hole blowing cooler drobe air in, but to be honest temps remained at 84!

So now waiting for another delivery which perhaps will be sent back - this is getting ridiculous!

Granger if I might ask your opinion - axial fans - what about if I separated the vent system - i.e. filter -fan- out, cool tube hooked up to axial (pc) fans on a timer so only working when lights on?

Or do you think I'm going to have to purchase a 6" extractor if I want to maintain the one system ventilation?

I can't wait til I win the lottery and have a whole basement floor designed by HVAC engineers!!!!

Hope the sun is shining for y'all

 

[oo2be]

Oops forgot to add, that if adding a new 6" then surely that's going to be more like a wind tunnel than ever!

 

[Granger2]

Axial fans have no power. If there's any resistance [static pressure] at all they won't do shit, regardless of cfm rating, etc. BTW, what's a "drobe?" A wardrobe? jeeze... -granger

 

[oo2be]

Yes indeed Granger it's a WARdrobe and its felt like a battle every step of the way

Thanks for repeating your message about axial fans, it wasn't that I didn't believe you the first time, just in the Vent 101 Red seems to make a case of using lesser powered fans (plural) to do the job of one big one so I kind of hoped due to finances I could blag using cannibalized pc fans - oh well back to saving the pennies for the Hyper 6" since I really really really want to use the 400w, until such time I'll thank my lucky stars that its getting there.

Tonights update - I removed fan and filter from the bungees on the roof after enough cursing to make someone with Tourettes blush and attached the 90 degree bends -only two initially on the hood's to ensure that the air was travelling uninhibited and put the filter on the floor. Still the same order Filter/Fan/Duct/90/hood/90/duct/attic and my temp has been constantly 77 for 5 hours. The attic exhaust temp is 81 so using the formula would appear to have 197 m/hr airflow.
This is a bit close for comfort to the filters absolute minimum operating flow (although still now sure about that since it removes the smell from a joint splendidly but in all seriousness now is the time to be discovering any weaknesses since if the house starts smelling then I'll be looking for new digs.

Which leads me to my next course of action -

I'm going to experiment a wee bit more with the layout, firstly trying it without the filter to see what kind of performance the fan gives unimpeded then try it with my original layout since the floor space really is premium and to lose approx half to the filter is making my eyes water, then I'll try it with the fan inside blowing up to the filter in the attic just to see what that's like.

Not sure what the script was before - perhaps the ducting was squashed in on itself or it was leaking but hey ho at least I'm getting there.

Finally, while I've got your attention - if I was to add another fan, what would you suggest? Do you think that the 6" Hyper would be overkill - physical size and power is its allure although a 6" and 5" in a drobe just seems ridiculous no?

Cheers

 

[oo2be]

I've just had a Eureka slap forehead in realisation of where my planning temps et al went wrong!!!!!!1

When i referenced the airflow for heat removal requirement formula, all the values are cubic feet per minute, I'd used 250, 400 and 600W with 5 degrees difference in what I thought was planning brilliance. Where I went wrong was used the CFM values but when buying fans compared it to the m3/hr ratings (CFM value 379.2 [600W] 644.64 m3/hr). I bought the TD350 without doing a conversion. What a fanny!!!!!! At least I know.

Thanks for your patience all -

 

[oo2be]

Grainger - you're not quite off the hook but scales are balanced. Mr Belvedere & Homer Simpson you're a pair of self santimonious twits who offer nothing positive so stay within you're means chaps, funnily temps evened out at a tasty 74 but humitity posing concern at 34% - to anyone else who reads forums - listen to granger/hosier/red and if you did the numbers with your growspace airflow - i.e. m3/hr )(doh) then trust you're own insticts. Too man idiot trolls xo Now to 400w in a 1ft sq space - cannae wait for the most efficient bulb "600.

Peace, believe you're dreams if you've done the groundwork - the moon's the limit

 

[oo2be]

P.S. cannae be ersed fecking about with eye hooks and bungee cords at 7ft tall anymore so gonna drill me a new hole ) for the cool tube - double spack to the forehead all of the vent 101 set up suggest BLOWING i been SUCKING .............Iwonder

 

[oo2be]

My apologies to all I was sampling home made cocktails and my alter ego took over, if any offence taken, then get over it it's an internet forum but seriously no good chi x

 

[oldbean]

I've read this on poo k420 but here I am totally lost, too long to read again. Given me a headache already

So.....wagwan?! Are the temps OK now and if so what did you change?

 

[angelgoob]

Intake holes near the plants. The plants absorb the heating wavelengths from the lights and therefore also need to be cooled slightly too.