Converting from CFL to HPS

[carrotsyo]

I've been unable to get the light I would like out of my CFL setup. with a 1'x2' area, the most I've been able to do is 2x40w and 1x23w and I still have heat in the mid 80's. I am unable to increase my airflow beyond my 100CFM 4" blower and 4" carbon filter because I don't want the noise.

I have been considering changing to a 100w-150w HPS setup and I have some questions.

1) It seems that the 150w might put me in the same heat situation so maybe 100w is better? I don't want to cool tube unless absolutely needed
2) I have to put the ballast in an external housing. What should I use in case it blows and overheats?

 

[jcmjrt]

A 1 X 2 area sounds about perfect for LED. The upfront cost is a little heavy but the savings due to less energy usage and not needing to replace bulbs will pay you back...and you wouldn't have the heat issues. I would be looking at about 90W. I use Kessil H350s but there are many choices including diy if you want to go LED. The one thing that I wouldn't do is buy the cheapest off e-bay that you can find. Good engineering costs money. Growershouse has some good prices on LEDs now.

 

[carrotsyo]

I don't mind DIY, but I'm found I usually end up spending more than just buying one off the shelf.

Link to DIY info? Anyone have experience running a 100w HPS? Will it put off less heat than 3x 40W CFL's?

 

[carrotsyo]

150w HPS got to 100 degrees very quickly in a cab that was ~85 with 3x 40W.

It definitely puts off more heat in spite of being much more efficient. I guess I'll have to try something to cool it. Mighty bright though, and this light is suppose to penetrate better than CFL's. It's definitely got a lot more lumens.

 

[medmaker420]

fix the ambient temps IN THE ROOM the cab is in and it will fix itself. You can't cool anything if the room temp isn't cool enough for it to actually happen no matter how much airflow is going on.

 

[carrotsyo]

fix the ambient temps IN THE ROOM the cab is in and it will fix itself. You can't cool anything if the room temp isn't cool enough for it to actually happen no matter how much airflow is going on.

The temp in the room is ~73 and I can't get it any cooler.

I put in the cool tube and the room still gets to 93F.

I think it might drop a little with some more airflow, but that would mean changing to a 6" fan with higher flow and maybe changing to a larger filter. I'm using a 6".

None of that is ok.

I think I'm going to buy a 100w HPS ballast and bulb instead. The light should be about the same as 3 40W CFL's, but MAYBE the heat will be lower?

I'm starting to think CFL's put off less heat for the same lumens..

----

Actually I think I was looking at some BS light online. My lights are 2600 lumens (65 LPW), and the 100w HPS is 10000 (100LPW).

I can only imagine it is going to be lower heat and would have to be more efficient than the CFLs because it uses less energy than 3x CFL's (which hit ~85F in the cab, with not enough light for 2 SQ feet.) It would provide enough light I guess. At least it would be more than what I can do otherwise.

 

[Jnugg]

Question are you exhausting back into the room your growbox sits in?

If so,vent into the attic or out a window via window exhaust box.

 

[elaromo]

vent

vent

You will have to exhaust the hot air outside. It sounds like you are exhausting into a closet in a room. Without exhausting the hot air outside, it will accumulate inside, resulting in higher temperatures. That being said the 90s isn't bad for MJ. It's just not optimal for most strains but I wouldn't worry about it until you hit the 100s. Also, if you circulate the air inside the grow box(small fan blowing on plants) and outside the grow box(ceiling fan), it will bring the temperature down. Get the 150 watt light because you will get bigger and better fruit from it for about the same amount of heat. The 150 will give you 6"-12" colas of rock hard nuggets in a 18"x18" footprint.

 

[farmari]

Some small wattage HPS ballasts use a rediculous amount of extra electricity in ballast losses. If a 150w HPS lamp is generating far more heat than 120w of CFLs than either the CFLs rated wattage is higher than actual (can happen) or the HPS ballast sucks. This can make PAR watt calculations rather complicated in HPS vs CFL when talking about 250w or lower HPS

 

[whitejamaican]

i also have a small cabinet about the same size as yours. I was running two 55W CFL bulbs and was in the 90's even with fan running full time, lots of light but too hot. I just installed a 100W MH (security light conversion) and the cab is much cooler with same fan. Plants are growing well.
Ballast is outside the cab now and I'm sure that helps too.

 

[carrotsyo]

I bought the 100W HPS setup and the first day (within a few hours) it was over 90F.

The lights were turning off for 12 hours so I let it slide and decided to check it when they came back on. The next day it didn't go above 85F. The next day it didn't go above 80F, and by today it's down to 77F max temp. Ambient temps are the same as they always are because the room itself is temp controlled.

So 100W ballast can indeed fly. Most quality HPS ballasts have a much higher efficiency rating than CFL's. The heat you get from a CFL is a result of the inefficiency.

This is going to work marvelously for me. I could indeed move the ballast outside of the cabinet, and I certainly will sooner than later.

When a traditional ballast blows, it burns up and it burns the (ceramic?) coating on the wires and it absolutely REAKS. You do not want that nasty crap on your plants. They have an estimated life of 2 years so I figured I would just replace it after 6Mo or so to be sure it doesn't blow in my cab, but it's probably a much better idea to put it outside the cabinet.