HPS...Heat Emission

I am about to get a 400 watt hps today, the only problem I am having is possible issues with heat. I have about 9 cfl's on the plants now (they are in a closet). My temps during the day seem to be between 84-91 degress. Here is my question.

With the 400 watt hps are the temps going to be too hot? Would temps of 100 plus be extreme and bad for the plants? Should I possibly consider just adding more CFL's instead of goign with the hps. I currently have only 1 fan in the closet running on low, with the hps I would most likely add another fan.


Please let me know asap, because I may get the hps this afternoon. THX

Pretty consistent temps of 95°+ will cook your plants like piece of bacon that got forgotten on the grill at a Waffle House.

What is your total cfl wattage now? Do you have the option of venting the HPS?

good comparison^^^

total wattage now is equivalent to 640 watts, I think real wattage is something like 1/2 or so. Venting is kinda hard, it is a closet with a door on it. If i get the hps i was thinking about adding another fan, and pointing one of them directly at the lights. what do u think

Do you have any system of intaking or outputting air from your closet? If the closet is just a closed box, all the fan will do is circulate the air that is already in there. If air cannot enter/escape the closet more quickly than the current air is heating, all your fans will end up doing is blowing the overheated air around. If you're in an area that is coming into summer, as outside temps rise and your plants grow and take up more room in the closet, temps are likely to rise further.

If you do get or have already bought the hps, I would only use it at a time when you could look in on your plants frequently to monitor temperature so that you will be aware of overheating early on. If your temps got to 100+ for any length of time I would guess that would be the end of your plants.

If you can't cut holes in your closet, maybe you could remove the door at its hinges and store it for the duration of the grow and make a new one out of some kind of board that you could cut an intake and outake into and then dispose of this and replace proper door at end of grow?

hiki0921 said:

total wattage now is equivalent to 640 watts, I think real wattage is something like 1/2 or so. Venting is kinda hard, it is a closet with a door on it. If i get the hps i was thinking about adding another fan, and pointing one of them directly at the lights. what do u think

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hey bro venting is always possible...where in the building is te room?
do you have any kind of space between the closet cieling and the next floor/attic? can you vent to the next room?

it is in a closet in the bathroom, we have a door on it with a deadbolt. There is about an inch of space at the bottom of the door. I could maybe use that somehow.....As far as cuttin into the door or the wall I cannot do that, I rent the house.

Let me know if anyone has any suggestions or ideas

Cut a hole in the ceiling the size of your vent hose.....when you move out you can cover the hole with an air conditioning vent....no one will notice a thing

thats not a bad idea, I guess I would have to get a vent hose too..anyone else?????

hiki0921 said:

it is in a closet in the bathroom, we have a door on it with a deadbolt. There is about an inch of space at the bottom of the door. I could maybe use that somehow.....As far as cuttin into the door or the wall I cannot do that, I rent the house.

Let me know if anyone has any suggestions or ideas

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nothing i havent done or are doing! when you leave a little patch will take care of the sitution.

A few weeks ago a guy posted common growing myths. One them involved HPS vs. CFL. He said that the real wattage of CFLs give off just as much heat as a HID. So going by that, you are already running the equivalent of a 320W HPS.

I'm inclined to say buy another cfl or two instead of spending all that money on a HID.

And I think at some point, without fresh air coming in, you just end up blowing all the hot air around in circles.

Found it.

https://www.rollitup.org/indoor-growing/66673-ten-myths-growing-under-lights.html

hiki0921 said:

it is in a closet in the bathroom, we have a door on it with a deadbolt. There is about an inch of space at the bottom of the door. I could maybe use that somehow.....As far as cuttin into the door or the wall I cannot do that, I rent the house.

Let me know if anyone has any suggestions or ideas

Click to expand...

A bathroom isn't the best place for your grow as it will be subject to huge temperature and humidity fluctuations if people are showering there and when flowering you need to maintain total darkness and if room is needed for toilet and shower at hours that don't fit in with your grow this could be a problem. It is also the room that is most likely to attract mould and fungus so you should make a particular effort to clean regularly. You should also take precautions if running extension leads in there to power lights or fans as electricity and a wet environment don't mix well.

If that cupboard is part of house and you didn't request permission from landlord to install that deadlock, it will look really suspicious if he inspects it at any time. He may ask to view the interior and if it is a fitted fixture, it would be difficult for you to refuse.

Maybe you should scout 2nd hand furniture shops or local for sale ads and see if you can find a cheap chest of drawers/cupboard/filing cabinet/chest to suit your grow. You could then cut it up as much as you wanted and would also be more portable and could be moved if you needed to conceal it.