Air cooled lights....
- Thread starter Kingrow1
- Start date
Jeremy Pivens
Well-Known Member
They are especially useful if you have like 25 thousand watts in a well insulated shipping container or something or your room will literally be smoking your weed for you.
Kingrow1
Well-Known Member
Starting to find in the UK they do nothing for the radiant heat from the bulb and my grow tent is cool enough till the winter stops with just a small extractor fan
Kingrow1
Well-Known Member
They do not cool radiant heat given off by the bulb but they do suck hot air out of the room, simple extractor and bare bulbs seems the same temps in my grow room
vostok
Well-Known Member
Air cooled lights.... to add metal halide lights, if still used ...lol
must have that 3mm glass sheet a fixed and secure
I've seen many of those fucking bulbs blow over the years
each time they are like a grenade going off
a good excuse for a big joint
never trust those MH bulbs but the HPS are grand
cheers/
must have that 3mm glass sheet a fixed and secure
I've seen many of those fucking bulbs blow over the years
each time they are like a grenade going off
a good excuse for a big joint
never trust those MH bulbs but the HPS are grand
cheers/
Jeremy Pivens
Well-Known Member
I understand what you mean, but I'm talking about sealed room industrial c02 grows. I'm just saying air cooled hoods definitely have their application. They also do help increase your bulb life, sounds crazy but I swear it's true.They do not cool radiant heat given off by the bulb but they do suck hot air out of the room, simple extractor and bare bulbs seems the same temps in my grow room
Jeremy Pivens
Well-Known Member
Bulb life doesn't sound like a big deal, but like I said, if you're running 25-30 lights, times that by 60or so bucks a pop(I like genesis bulbs) , they get expensive..
Dr. Who
Well-Known Member
You need to figure that the radiant heat is part of your environmental, thermocline set up.They do not cool radiant heat given off by the bulb but they do suck hot air out of the room, simple extractor and bare bulbs seems the same temps in my grow room
Mid to high 80's at the canopy. Low to mid 70's at mid plant, and 67-70 at pot level. You adjust hood height to help set this. The ambient room thermostat placement is also critical to holding this environmental set up method.
I run 8 lights per 12X24 "room". If I didn't use hooded fixtures. My temp control costs would be out of bounds...In cold months I rely on simple Greenhouse thermo switch's to control ambient temps - No AC needed (It turns on exhaust fan, pulling in cold filtered air). Placement is again, critical.
Last edited:
Kingrow1
Well-Known Member
The actual air cooled lights do not block any radiant heat, there fore whether bare bulb or air cooled the thermal emission is the same.
What are your lights cooling then?
OldMedUser
Well-Known Member
Most of the heat given off by HID lights is thermal so if that can be removed separately from the room's air then the atmosphere in the room is not affected, think CO2 levels, and the temperature of the room can be greatly reduced without so much costly A/C. By cooling the bulbs their life and spectral integrity are both extended so it's a good method to reduce costs at many levels.
I need the heat in my cool basement so just make sure I have a small fan blowing across the bulb to cool it down a bit and mix that warm air into my room. The larger oscillating fan keeps it all evenly blended.
OldMedUser
Well-Known Member
I've never had an MH light blow since the first one I bought in '82. Nor an HPS. I've heard they do blow using digital ballasts but I only use magnetics so maybe that's the difference. Something about resonance from the higher frequencies from digitals I seem to recall reading.
Kingrow1
Well-Known Member
I would like to think most heat given off by HID's is radiant and that is from the light converting to heat through the laws of thermodynamics. The bulb and the unit can be cooled but not the radiant heat emmited, that requires the plant to perform transpiration and then the ambient temperature (humidity wind etc etc) will dictate the rate the plant can cool.
I get little temperature difference from bare bulb or air cooled on plant surfaces so i'm not cooling the plant in anyway by cooling the bulb
klozetgrow
Well-Known Member
In a closed closet space I can feel the heat of my bulb by putting my hand under it turn on air cooled hood heat is no longer there I am by no means educated in thermal science but am great with practicality less heat in feeling on my hand the less heat the plants are feeling?
vostok
Well-Known Member
one time '95 we had 3 x400w iwasaki? bulbs blow one after the other, even then we were debating removing the safety glassI've never had an MH light blow since the first one I bought in '82. Nor an HPS. I've heard they do blow using digital ballasts but I only use magnetics so maybe that's the difference. Something about resonance from the higher frequencies from digitals I seem to recall reading.
stoned we thought it was gonna be a shoot out with the cops and 'we' the Indians ...funny as fuk ..lol
we thought it was the cold but in fact just old, my first search at wiki ...lol
-----
All HID arc tubes deteriorate in strength over their lifetime because of various factors, such as chemical attack, thermal stress and mechanical vibration. As the lamp ages the arc tube becomes discoloured, absorbing light and getting hotter. The tube will continue to become weaker until it eventually fails, causing the breakup of the tube.
Although such failure is associated with end of life, an arc tube can fail at any time even when new, because of unseen manufacturing faults such as microscopic cracks. However, this is quite rare. Manufacturers typically "season" new lamps to check for such defects before the lamps leave the manufacturer's premises.
Since a metal-halide lamp contains gases at a significant high pressure (up to 50 psi), failure of the arc tube is inevitably a violent event. Fragments of arc tube are launched, at high velocity, in all directions, striking the outer bulb of the lamp with enough force to cause it to break. If the fixture has no secondary containment (such as a lens, bowl or shield), then the extremely hot pieces of debris will fall down onto people and property below the light, likely resulting in serious injury, damage, and possibly causing a major building fire if flammable material is present.
The risk of a "nonpassive failure" (explosion) of an arc tube is very small. According to information gathered by the National Electrical Manufacturers Association, there are approximately 40 million metal-halide systems in North America alone, and only a very few instances of nonpassive failures have occurred. Although it is impossible to predict or eliminate the risk of a metal-halide lamp exploding, there are several precautions that can reduce the risk:
- Using only well designed lamps from reputable manufacturers and avoiding lamps of unknown origin.
- Inspecting lamps before installing to check for any faults such as cracks in the tube or outer bulb.
- Replacing lamps before they reach their end of life (i.e. when they have been burning for the number of hours that the manufacturer has stated as the lamp's rated life).
- For continuously operating lamps, allowing a 15-minute shutdown for every seven days of continuous operation.
- Relamping fixtures as a group. Spot relamping is not recommended.
- Ensuring that the fixture includes a piece of strengthened glass or polymeric materials between the lamp and the area it is illuminating. This can be incorporated into the bowl or lens assembly of the fixture.
- Using lamps that have a reinforced glass shield around the arc tube to absorb the impact of flying arc tube debris, preventing it from shattering the outer bulb. Such lamps are safe to use in 'open' fixtures. These lamps carry an "O" designation on the packaging reflective of American National Standards Institute (ANSI) standards.
(https://en.wikipedia.org/wiki/Metal-halide_lamp)
I no longer use MH lights
Kingrow1
Well-Known Member
I can replicate this also but only when the air cooled hood pulls air from the tent which is why i feel cooler, if i run the aircooled lights sealed and turn of tent ventilation its hot as hell if i stand underneath them, 70,000 odd lumens beating down on my head dont half get hot.
I get what some are saying, surely aircooled lights help with the heat a little but they do nothing for the radiant heat that gets given off with the light. Ive realised that i get better results basing my extraction on air temps only and where i live only requires a small amount of extraction to keep well under 25 most of the year.
klozetgrow
Well-Known Member
Wish I had it that easy a garage in the middle of summer in az don't stay cool very well specially said cabinet in garage lol
OldMedUser
Well-Known Member
I do.
klozetgrow
Well-Known Member
And the "heat" from an air cooled hood would be the p.a.r. not ambient heat no?
klozetgrow
Well-Known Member
Do you use mag or e ballast? Looking for a 400 w mh ballast but don't want an eballast haven't been able to find a complete mag mh set up just partsI do.