Need help with Cobs, Heating, AC , etc

[arcalion]

So i was looking to get into COBS because im hearing that they generate a whole lot less heat, or is easier to manage.
Ive currently got a room thats 8x10 that has two 1000W bulbs in there without any AC, but i've currently got them running at 750W. my heat is currently 85F which is a little high and it is becoming summer so its only going to get worse.

Would Cobs be the right choice? will i still need to get AC? ATM it would be quite hard setting up a split unit because we would have to rewire stuff too the outside, yet we have a tenant and want to be a little discrete about everything.

I was going to go with the Timbergrowlights Vero 900W fixtures x2 . i was wondering if this wouldnt generate as much heat as my HPS Bulbs
Thanks!

 

[HydoDan]

1800 cob watts is still going to put off as much heat as your 1500 hid watts...
But with a dimmer option you can adjust the cobs to meet your changing environment...
600 cob watts will out grow 750 hid watts.. 750 cob watts will out grow 1000 hid watts... Imo
Timber is a great place to do business.. I have their 6 cob 300 watt Cree kit... Out growing my old 550 watt hps system..
Keeping temps @ 82 tops... Hid would hit 90+ ... Yes cobs are the way to go..

 

[frica]

900W will always be 900W and heat a room as much as any other 900W light in a closed room.

So 1800 cob watt will put more heat than 1500W HID.
But more yield.

If you dim the double fixture to for example 1000W, you will still have the same yield as 1500W HID but less heat.

 

[coreywebster]

What you want to work out is how many watts of cob you need to create the same or more light than you would with hps equivalent, Then you will be running just as well with less watts and thus less heat.
So for example you could run 1200w of COBs and still have more light than your 2x 1000w hps. Plus the added benefit of multiple light sources, so less shading, more light from different angles to your plants.

 

[arcalion]

What you want to work out is how many watts of cob you need to create the same or more light than you would with hps equivalent, Then you will be running just as well with less watts and thus less heat.
So for example you could run 1200w of COBs and still have more light than your 2x 1000w hps. Plus the added benefit of multiple light sources, so less shading, more light from different angles to your plants.

Ok, if i did that would i still be able to get to the goal of 2lbs+ a month, i usually do perpetual grow. and if it ran 1200W of cobs would that heat be under 80?

its just that the two fixtures are 4500$ canadian,
a minisplit unit is 1400 if i got it to work and i could run 2k watts HPS fine

 

[coreywebster]

Ok, if i did that would i still be able to get to the goal of 2lbs+ a month, i usually do perpetual grow. and if it ran 1200W of cobs would that heat be under 80?

its just that the two fixtures are 4500$ canadian,
a minisplit unit is 1400 if i got it to work and i could run 2k watts HPS fine

Depends on if your running your lights at the moment air cooled? If not then you should knock off a few degrees at least.
If your creating the same amount of light or more than you were then you should produce the same yield.
I have turned to cobs but my first grow with them isn't finished yet. . All I can say is there are loads of folks who are pulling great yields all over here.

Build your own for less $. There are some amazing prices on all the materials these days. Its really simple to do too. REALLY simple.

 

[HydoDan]

Have a look at the Citizen cob light.. I paid dearly for my Cree cobs and would go with citizens if I were to buy today...
What kind of air flow do you have?... DIY would save a lot of $$

 

[arcalion]

Have a look at the Citizen cob light.. I paid dearly for my Cree cobs and would go with citizens if I were to buy today...
What kind of air flow do you have?... DIY would save a lot of $$

i just have one exhaust fan running in the room; i forget the rating but its more then 800cfm. my doors closed so theres a lot of negative preasure and so the window in there thats closed, i still get air leaking from outside. i wish i could leave the room opened but then id have light leaks.
i just want to be able to do all 2,000watts without the need of a minisplit. but it seems like its a must regardless of cob or not. its the first thing i should get before upgrading lights..

 

[nevergoodenuf]

The COBs have a couple advantages. For your situation, the biggest advantage is the lack of IR. That is the pure heat that you feel from your HPS. This means your canopy temperature will be much lower under COB, allowing you to run 4*-6*f high to have the same canopy temps. I do run CO2 but it is more so I don't have to hear the fans all night. I keep my room 83*-85*f.
The other day I ran a 950w COB led in a sealed (no intake or exhaust, just wall fan moving air inside) tent for over an hour to see how hot we would get.

 

[arcalion]

The COBs have a couple advantages. For your situation, the biggest advantage is the lack of IR. That is the pure heat that you feel from your HPS. This means your canopy temperature will be much lower under COB, allowing you to run 4*-6*f high to have the same canopy temps. I do run CO2 but it is more so I don't have to hear the fans all night. I keep my room 83*-85*f.
The other day I ran a 950w COB led in a sealed (no intake or exhaust, just wall fan moving air inside) tent for over an hour to see how hot we would get.
View attachment 3925885 View attachment 3925886

ok that seems good. thing is ill be running 1800W of COB, with the exhaust fan that runs at 900cfm, even if its 86-87F in the room its still ok for masterkush? also with the two 750watts ran in my room it took a couple hours, maybe 7hours to get to 85F. if it takes the cob lights to take longer that would be great too.
Maybe ill have to get into CO2 as well for the summer if it does get to hot

 

[nevergoodenuf]

If you are building them, get the B version drivers ( if using mean well) and you can throw a thermal switch on the dimming circuit to cut power if it hits a curtain temp.

 

[arcalion]

If you are building them, get the B version drivers ( if using mean well) and you can throw a thermal switch on the dimming circuit to cut power if it hits a curtain temp.

how much cheaper would it be for me compare to buying an already made one from Timbergrow 900W vero v7? and how does it cut the power? like completely or does it just dim it down until it hits a certain temperature and stays there steadily?
Also checked out your grow, looking good. are Fabric pots much more amazing then regular pots? i was thinking of switching since i notice my veg takes forever!

 

[nevergoodenuf]

how much cheaper would it be for me compare to buying an already made one from Timbergrow 900W vero v7? and how does it cut the power? like completely or does it just dim it down until it hits a certain temperature and stays there

I that would be more advanced building, but the possibility is there. There are a lot of different choice for build and is that hard with some of the DIY kits available.

Also checked out your grow, looking good. are Fabric pots much more amazing then regular pots? i was thinking of switching since i notice my veg takes forever!

Thanks, I have been a big fan of fabric pots. They cannot get root spiral (that I have seen) and you can throw them in the laundry between grows. Here is a 3 g pot I got over 160g using 20w per square foot of COB lighting.

 

[CobKits]

with arduinos you can do all kinds of crazy shit with dimming

 

[arcalion]

I that would be more advanced building, but the possibility is there. There are a lot of different choice for build and is that hard with some of the DIY kits available.

Thanks, I have been a big fan of fabric pots. They cannot get root spiral (that I have seen) and you can throw them in the laundry between grows. Here is a 3 g pot I got over 160g using 20w per square foot of COB lighting.View attachment 3925910

Ill probably stick to the pre-built which i dont mind, also since you use 3g fabric pots how big does the plant generally get by the end of the cycle? with my regular pots i start getting my plants tipping over haha.
I want to stick with 3g Fabric pots but how often did you need to water?

with arduinos you can do all kinds of crazy shit with dimming

im going to remember that maybe ill add it in afterwards. im going to have to order these cob lights pretty soon as it starting to get a lot water outside!

 

[nevergoodenuf]

Every run is different. With 5'ers it was every other day. With 3'ers every 3 days.

 

[arcalion]

Every run is different. With 5'ers it was every other day. With 3'ers every 3 days.

Hmmm im in Pro-mix HP right now, so theres a possibility it make dry quite quick haha. ill give it a go. going to go to the store and try buying a couple pots to try out.

 

[HydoDan]

I grew in fabric pots outside last summer.. I had to drive stakes into the ground thru the handles to keep em upright..
Windy days dried them quickly.. I had to water twice a day.. Indoors every other day.. I'm sold on them..

 

[REALSTYLES]

I'm in a 4 x 8 tent with no A/C as well but running about 2000w out of 2400w of Cree CXB3590 over 56% efficiency

 

[MMJ Dreaming 99]

The COBs have a couple advantages. For your situation, the biggest advantage is the lack of IR. That is the pure heat that you feel from your HPS. This means your canopy temperature will be much lower under COB, allowing you to run 4*-6*f high to have the same canopy temps. I do run CO2 but it is more so I don't have to hear the fans all night. I keep my room 83*-85*f.
The other day I ran a 950w COB led in a sealed (no intake or exhaust, just wall fan moving air inside) tent for over an hour to see how hot we would get.
View attachment 3925885 View attachment 3925886

Okay. Good info in this thread. I am looking to make some changes for summer. I see the alternatives to HPS heat as:

1. Have glass and vented hoods and a sealed system sucking heat out of the rooms with 8 inch fan and sucking cool air in. Advantages - cooler but still warm and using lots of HPS power. Top of the line is AC/DE setup with vented hoods and DE but SE is probably fine.
2. LEC 315s - two to match a 1000 watt HPS SE. Cooler but how much?? Expensive up front cost. Can it pull 2 to 2.5 lb per light which I can do with 1000 watt HPS hydrofarm cheapies.The costs seems more than QB and LEC bulbs need to be replaced like HPS.
3. COBs - Cooler but how cool. Saves energy over 1000 watt HPS. Higher up front cost. Can it pull 2 to 2.5. Lasts longer than HPS bulbs. More DIY skills needed than QBs??
4. QB Boards by Samsung and Northern Grow Lights. Much cooler than anything else. Uses half the power of HPS factoring cooling costs. More expensive than SE and DE HPS but not too bad. Last long than HPS Bulbs. Can it pull 2 to 2.5 a set up?