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BuddyBoy
12-06-09, 12:25 AM
So folks here's the dilemma. A few of you will have read my grow diary, and the associated problems with heat that fried 2 of my plants with a direct blow fan (the perfect advertisement for the need of an OSCILLATING fan). And the purchase i made of a heat shield.

I fitted the heat shield with a little modification, but it sits same distance from the bulb and essentially its exactly as the instructions say....So what might the problem be i hear you ask?....Can't be heat...., he bought a heat shield for that...!

Well the problem is heat lol :satan:

Before i fitted the heat shield the lights on temp was anywhere from 72-79. Acceptable temps, very acceptable, and a bit of bother i had getting to that, but not too much. The whole story is this is my first grow with a 400w, i have been growing for years with a 250w, anyways, with the heat shield in place i decided to monitor the situation this evening, in less than an hour the ambient temp of the room was 88, and 92 when i left, The oscillating fan is on full and the extraction is now cranked up to full also.

Still over 90. I had to leave it tonight with the vent flaps open in the hope that extra venting will get the temps down...

WTF! A heat shield and temps up?

Has anybody else had the same experience, or similar even? And if so, a solution/suggestion would be helpful, short of removing the shield that is. I am flabbergasted to say the least. I even raised the light back to 15inches above the canopy to reduce the damage i would expect from that kind of heat at this stage, and considering i think one of the plants is unusually sensitive.

At this rate i am gonna just put the 250w bulb back in and take the yield hit for next time...

I probably wont, but with the demise of 2 plants already, great buds though, i just gotta keep them alive till they finish...And my outdoor woes on top i am having a hard day...lol

I sound pathetic i know:jawdrop:, however i still have a whole lotta fight in me, so a few suggestions might unfreeze my thought process...

Thanks in advance :)

Bliss118
12-06-09, 07:52 AM
Hi im also having heat problems in my rather small 400wat grow room i also got a heat sheild and have been able to lower my light and not burn the plants but my temps high spot is about 30+ degrees ive been leaving the door slightly open to in the day time to keep the temps down untill i can afford to fix it however my extraction is only a bathroom extractor from bnq that removes aprox 85lter per hour what are you running?

BuddyBoy
12-06-09, 10:24 AM
Hi im also having heat problems in my rather small 400wat grow room i also got a heat sheild and have been able to lower my light and not burn the plants but my temps high spot is about 30+ degrees ive been leaving the door slightly open to in the day time to keep the temps down untill i can afford to fix it however my extraction is only a bathroom extractor from bnq that removes aprox 85lter per hour what are you running?

I have a 125mm Ruck on the go with a good filter that can handle the CFM adequately, in usual circumstances more than enough to dissipate that heat in that space...and some.

Its the heat shield that has raised the ambient temps, nothing else, i can check this accurately by looking at my min/max hydrometer.

I can't leave the door open, and I already use all the venting possible, 3x400mm2 flap vents, and I also have ducting running through the internal fan/filter/unused cable socks to keep them wide enough to allow proper airflow.

I'll be checking again today, but i think its gonna have to come down and go back to how it was, a surefire waste of £18.90 incl of postage....

We shall see.....

:)

BuddyBoy
12-06-09, 10:28 AM
p.s. my Ruck circulates 285ltrs per hour, and the filter can handle nigh on 300ltrs per hour. Should be no problem except the heat getting trapped and reflected back into the reflector. I have a very efficient reflector, one of the best about, looks like its a little too efficient with the heat...

Bliss118
12-06-09, 11:31 AM
Without trying to sound insulting to some one who obviously has better knowlage than me on the subject is the heat sheild the right way around i almost put mine on upside down lol

nydiesel
12-06-09, 11:33 AM
Heya m8,

I had the same issue until I ducted an intake from a window, really cold air goes down the tube when it gets to my tent a oscillating fan blows the cold air at my light, another circulates air around and my CF takes it out the top.
I have one small passive open to help with the ducting in.
I get around 28/30c tops compared to high 40c on cool days and 50c on hot!.

Air con units work well, even the ones that are just a blower and you pop an ice tray in the bottom. But this is an ongoing fix not a simple tube here and voila!.

Ice pack in ducting? meh this is such a common problem and one of the hardest to fix (well so I have found)

All the best m8 if you do already have ducting in .... i dont have a clue... but i tried!

Ny,

weed heed
12-06-09, 12:11 PM
hiya buddyboy,am sure the heat shield is jist for hotspots nothin to do with ambient air temps,but it still leaves the problem of heat inthe room which am sure will be because we are in summer time now so the ambient air temps are higher we all have a raised air temp probs in the summer months,nyd isny far wrong when he says draw fresh air from the outside if poss.weed heed

jobby2812
12-06-09, 12:47 PM
The only thing I can think of with the heat shield is instead of the heat being directed straight down at your plants without it on, it pushes/spreads the heat out. I have a shield for my 250w hps. I can now get my hand within about 2 inches under the shield but when I move my hand out to the side I have to hold it further away. Not sure why that would put your ambient temps up unless it's down to the positioning of your thermomiter. As said though you need a good intake and out take air flow.

BuddyBoy
12-06-09, 01:22 PM
Thanks chaps, i have noticed that the heat towards the sides is hotter than directly under the shield, i am guessing the best use of this product is one plant directly under the light. Also my therm is there as well, ill move it today, but i have to say that as soon as i unzip the tent the temps are noticeably warmer to feel, i am not just reading the therm.

Yes i do have it the right way up lol, but it never hurts to ask! The amount of people who put their inline fans backwards is testament to that ;).

My temps are a constant 50ish in the tents location, summer and winter, so my outside influenced temps are fine, but good suggestion, thanks, however thats not the cause.

Air from a window is impossible :(, i have no way of opening the only window in that out building, and i'm not prepared to buy another ruck for intake, i only grow 4 plants a cycle, not a room full, up until the 400w this was a small setup, and done with a budget in mind, also a close calculation on how much i smoke.

The quest continues, i might just have to remove the shield for a couple of day and double check the change is diretly related...

Thanks again everybody, if anybody else has a suggestion or 2 i would be grateful....

:)

nydiesel
12-06-09, 01:50 PM
I decided to have a look for "mini air con units"

Maplins:

£40

* Full function remote control operation
* 2.5l ice compartment for extra cool air!
* Built-in air filters remove micro particles in the air flow to create fresher air
* Selectable 3 wind speeds - low/medium/high
* Humidifying capacity 6.5 litres per day
* 100° oscillating sweep angle
* Built in timer control from 0.5 to 7.5 hours and continuous operation
* Mounted on castors for easy transportation
* 2m power lead

Q- What's the overall size of this product?
Answer- 300 x 300 x 620mm.(LxDxH)

I also ran a search for DIY air con units on google.... amazing m8 someone has converted a styrofoam burger box with a pc fan and ice (apparently salt on ice keeps it colder for longer?) and a cool box portable air con unit. (about 5 squid for the 1st one and 10 for the 2nd)

I think this is the way to go in an enclosed space!!

Ny,

BuddyBoy
12-06-09, 02:28 PM
I decided to have a look for "mini air con units"

Maplins:

£40

* Full function remote control operation
* 2.5l ice compartment for extra cool air!
* Built-in air filters remove micro particles in the air flow to create fresher air
* Selectable 3 wind speeds - low/medium/high
* Humidifying capacity 6.5 litres per day
* 100° oscillating sweep angle
* Built in timer control from 0.5 to 7.5 hours and continuous operation
* Mounted on castors for easy transportation
* 2m power lead

Q- What's the overall size of this product?
Answer- 300 x 300 x 620mm.(LxDxH)

I also ran a search for DIY air con units on google.... amazing m8 someone has converted a styrofoam burger box with a pc fan and ice (apparently salt on ice keeps it colder for longer?) and a cool box portable air con unit. (about 5 squid for the 1st one and 10 for the 2nd)

I think this is the way to go in an enclosed space!!

Ny,

Thanks for that bro :)

That would be half of my growspace lol, with the fans, filters and everything i have in their anyway lol.

Nice suggestion, however not feasable unfortunately.

The styrobox could be interesting, however the temps in a small space would melt the ice in under an hour, not enough cool ambient temperature, i have read about people with frozen bottles of water in front of fans, this lasts less time, even with salt, which makes the ice cooler thus melting slower....

cheers though.......next ;)

:)

nydiesel
12-06-09, 02:45 PM
Hmmm!

Prem-I-Air Mini Air Cooler

3 speed settings. 1 litre water tank capacity for cooling or humidifying. 500W fan heater. Oscillating vertical louvres for wide distribution. Ideal for a desk or night time use. Size: (H)28, (W)20.5, (D)22.5cm.

Not sure how much but it's the smallest air con I have found.

Could you reflect the heat coming off the heat shield towards a fan? (bit odd to do but if its flowing out the sides of the shield it could be a possibility)

An Ice pack will last a lot longer than ice due to the chemical substance used inside it.

A large bottle compared to a little bottle of frozen water will last a lot longer.

Damn you got me thinking now m8....

Ny,

BuddyBoy
12-06-09, 04:33 PM
lol, and yet another £40 with delivery....nice bit of kit, but to be honest i have spent enough already this year on my growing lol, Mrs BB would have a fit, i got away with the upgrade to a 400w lamp, and the associated 125mm fan and filter, and looking over my shoulder she sees me eyeing up a small tent for a veg/clone space (i would really like to keep a cut of this sativa dom hybrid i have growing)....so in short......no chance lol.

I appreciate your efforts, but i am gonna see how we fared last night, it might just be ok, you never know, besides if the air is warm, but fresh its not a problem, its just a problem if a fan constantly blows the heat on the same plant (I am an expert at this) for a elongated period of time, or the light is too close to the plants.

30 degs ambient might be ok, as long as i keep the plants hydrated, which means a fine line between damp and too wet...

I'll get there in the end, and were on the home stretch with this grow.

Cheers mate :)

Cridiba
12-06-09, 10:27 PM
Heat shields are for stopping hotspots so you can get your light closer to the plants. Maybe the heatshild is deflecting heat to other parts or your room that already has loads of heat hence increasing it somewhat. Try moving your therm below the heatshild and just see if there is a drop in temp?

BuddyBoy
14-06-09, 01:17 AM
You will al pleased to know, i hope anyway, the the heat shield is solved, and i am officailly to baked to be aware of what i am doing in the grow room presently...I'll explain lol.

I was experiencing low night time temps, so i put a heater in the space but forgot to put a tomer on the thermostat, so it was coming on yo maintian a temp, just before lights on and lights off, due to the drop in temps, so anyway i am standing there and feeling the heat, and by this thread you can see i was concerned...

So ai m standing there abd i can feel this warm breeze, like hot breeze really om my leg, and i just thought my fan was blowing the hot air aound, if i didn't drop my scissors i would have never discovered the fan heater on, now i have the room is back to late 70' early 80's lights on and 60's light off.

Order has been restored....

Doh, i swear this is gonna be my last grow, for some reason this time, with the new additions i have been like deer in the headlamps, and forgetting all the basics, a lesson true enough.

Not from today onwards, lol, i will be paying much closer attention, like all my previous grows, nothing like taking it all for granted and getting caught out by your own complacency...

Back on track, and one of my ladies is just prolific with budding now, and the frosting is paralount lol, like i say back on track :)

Thnaks for all the help chaps :) Appreciated for sure :D

dekay
14-06-09, 02:20 AM
Lol, money rarely solves problems. its always something simple.

weed heed
14-06-09, 03:07 AM
hahaha,thats class buddyboy glad yer problems sorted all the best wi the rest of yer grow.weed heed

Father jack
14-06-09, 09:33 AM
i feal your pain BB!

i had like 3 diffrent ways to control temps lol 2 80mm pc fans for intake outtake and desk fan on full pelt those failed! i mad a box out of cardboard and stuck a fan heat in it set to cool and taped some tumble dryer hose to it to force the air from the box into the room that failed lol i have since left the 4/5 inch passive open stuck my desk fan on full put it on its side blowing up/onto the 250w cfl so the refector acrs as a duct and it takes the heat away and blows it up into the top of the box whare there's another 4/5 inch outtake this time with a fan heat taped ( yes i know what your thinking hehe check the vid on my diary! ) to the top of the box so the fan sucks the air out hehe bit redneck style but it works a charm temps stay around 79.5f a little higher than i`d like but better than 85++f lol

here have a look lol simple but it works :P

since that vid was taken i have painted the inside white and got rid of the other 2 pots lol

http://www.youtube.com/watch?v=bjiamo0t67U

BuddyBoy
14-06-09, 11:27 AM
Its has to be said, sometimes growing superb weed has its downsides, as you have witnessed here, too baked to pay proper attention to my grow this turn around, I should be ashamed of myself....:p

Yes complete agreement from me dekay, throwing money at something is not the answer at all, i nearly bought the mini aircon unit as well, ha, not now! :p

Which bit is class weedheed? my divvyness for the heater being left on and amusing y'all lol? or the fact my heat problem is solved, for the time being anyhow ;) Thanks though mate, lol, i know what you meant :D

FatherJack, interesting setup there mate, I love mini DIY grows, infact I am gonna be starting a min stealth grow myself in the near future, the space will be 1sq ft, and I hope to yield an ounce, using only a 125w blue, and the same red cfl. Just a quick question Jack mate, whats the upturned coffee mug for? A bit of light refreshment while working in the space? :D

Suffice to say, we're back on track, i just have to remember my weeks as well, i seem to think I might have my diary wrong by a week, but to be honest i am too baked to remember that as well....bloody Nora, i have really let myself down this time....

Cheers chaps :D

Father jack
14-06-09, 11:30 AM
Well normally yes it has coffee in it but this time it had a shot glass inside it with my seeds in som water :) had no whare warm so i put the cup over it to block light but also to keep them warm while they were germing

yea pitty i killed the bathroom fan LOL it worked great for half an hour then went fizzle pop so i`l have to replace it before we move or the council will whine about it no dout

BuddyBoy
14-06-09, 11:43 AM
yea pitty i killed the bathroom fan LOL it worked great for half an hour then went fizzle pop so i`l have to replace it before we move or the council will whine about it no dout

was there a buzz along with the fizzle pop? lol, just be careful mate these little bits like bathroom fans are not ip'd enough for moist grows, danger, danger....high voltage! lol

Like your little video though :) Are you the new David Ballamy? Running commentart could be good, i feel and editors moment.....

:D

Father jack
14-06-09, 12:57 PM
was there a buzz along with the fizzle pop? lol, just be careful mate these little bits like bathroom fans are not ip'd enough for moist grows, danger, danger....high voltage! lol

Like your little video though :) Are you the new David Ballamy? Running commentart could be good, i feel and editors moment.....

:D

yea it slwoly went south on me lol pair wee thing!

roll on thrusday hopefully get the rest of my stuff from greens

i was thinking about taking a pic everyday of the plants untill harvest then speed them up a bit