Can someone please help me out with venting my wardrobe i currently have a 250w hps bulb i have a hole cut out the same size as a tumble dryer hose leading straight to an outside vent i also have a fan that comes on for 30 mins every 2 hrs i know i need a extractor fan but im unsure exactlly where to put it and how to hook it up

Any info gratefully accepted

CLennonUK

Just thought id add that i have just completley fried my 12 day old mazar all 4 of them

I can tell you what i did.My drobe is old and sturdy,so i got 2 four inch fans,the in fan i placed about 18 inches from the floor and the out fan is on the top with the ducting the same as yours.Dont worry about the breeze blowing on the plants as it makes for a sturdy stem.You sound as have got the rite stuff for the job,good luck

Read your post again,as for hooking it up,the fans i have are like sunbed fans and the conections are on the side,so you run a loop through them to the timmer plug,then they come on together.Hope this hels

If i only got one hose that is coming in at the top and leading to a vent how will i get the air to get out i thought that when the fan was on the air could be pushed back up same hose and out vent but its obvioulsy not workin as they have all just died

I didnt have this prob with my first grow because they were in a more open space not in a wardrobe and i was using a enviro so it didnt get that hot in there.

Not sure i follow your current set up clennonuk.

But whatever, with a HID in a closed drobe, your going to need proper extraction. I had an inline 4" fan coupled to a carbon filter in the top of mine. Light proofed passive inlets allowed complete air recirculation from the room the drobe sat in.

I guess keeping the doors open and using an oscillating fan during ALL lights on hours may see you through in the short term. That may not be an option though.

Do extraction fans eat up much elcectric and do they have to be on constantly

No and pretty much yes when lights are on ......

RAZ

They only cost pennies to run mate, and if you hook one up to a controller, it will only run full-pelt when it needs to.

You need a proper 4 inch duct fan capable of moving at least 160 cubic metres an hour. This can be mounted anywhere above the light. A proper in line duct fan will also be capable of pulling air through a filter. If you add a filter use a fan that will shift at least 175 cu. meters an hour. One or two 4 four inch holes at the bottom will alow plenty of air in. They need to be light proofed.

In a similar set up I used a small clip on fan (about a fiver from b&q) for air circulation. I had it gently blowing across the tops of the plants.

To keep humidity down I had a second bathroom extractor fan timed to come on during lights out. (If you can afford it a climate controller will run fans at full speed or tick over as needed.) My main extractor was conected to a thermostat. I hang my fans and filters from bungee cord or chain fixed to the roof.

With your present setup you need to run your fans constantly during lights on. What is the temperature and humidity in your drobe?

there are billions of threads on this - stickyfingers has outlined the main requirements - DON'T faff about with computer fans only, (they're good for circulation, but not extraction through a filter) - or your plants will die, you may well have a fire! An hps if treated with respect is safe, but you MUST have a proper duct fan, or you're going to get into trouble!

A few comments here.

As for in-line duct fan and carbon filter mentioned in above posts - I agree totally. Especially as its HPS for fire safety reasons.

Heres a picture of my set-up, no camera so scuse the crude drawing, it may give an idea.

[attachmentid=31089]

And lastly, regarding intakes, this is a question, how can you make wardrobe intake hole light prooof but will also allow air in, I have looked round these boards and seen baffles etc but wonder if a baffle will take up too much room for me and not be discreet enough.

Hope the picture helps anyone whos planning a drobe.

emdeema

I used some metal ducting. Painted it matt black inside and made a couple of bends. It ended up light proof.