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  1. #1
    Senior Member Bonaqua's Avatar
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    Space between 250W MH bulb and the reflector?? URGENT!!!

    I'm mounting the bulb and home made reflector on the aluminum rail ( U profile).
    What would be the minimum distance from the rail to the bulb?
    Urgent please. I'm doing it now.
    Thx.

  2. #2
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    Most drop down "L" brackets put the bulb about 3" from the reflector DEPENDING on the shape of the deflector. I would say that if you want the minimum distance .. go no closer an 1.5 inches. that will allow you to grip the bulbs when changing is required.
    Rob

  3. #3
    Moderator ShipWreck's Avatar
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    Not to highjack the thread but what is the minimum distance between the bulb and the wood of the canopy (to the side of the bulb)?
    Rob
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    Upgrade in the works! Keep looking for an update.


  4. #4
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    I will leave that one to someone else because I would not mount MH or other high heat bulbs below unshielded wood. OH it will work with no problem for some time but over the long haul that heat will dry out that wood some much that it will be like kindling. IMO it would be a fire hazard !!!
    Rob

  5. #5
    Senior Member Bonaqua's Avatar
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    OSD, I agree that the wod would dry out, but not much, in my opinion. You still have a large evaoration going on, that would keep the wood moist, I think.

  6. #6
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    There is for sure a lot of evaporation and the air over the tank is laden with moisture. However that moisture will only be forced back out of the air when a change to a lower temperature is encountered. Your not going to find lower temperatures in the canopy space even if fans are in use. So IMO the wood will remain dry and toasty.
    Rob

  7. #7
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    never mount a MH lamps within at least 6'' of wood!
    for example, I had mounted my lamp within my PFO reflector but didn't use there cutout, instead, I mounted closer to the edge. this left a hole [cutout] and the light just escaping from there [around 5'' distance] started to slowly burn the wood after a few weeks. I had to cover that hole with metal.

  8. #8
    Moderator ShipWreck's Avatar
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    I just wired the canopy on sunday and found that the wood on the one side is getting warm (no fan at that point) about 3.5" from the wood. The top above the reflector did not feel warm at all during the same time. I was thinking of covering the side with just a flat piece of aluminum against the wood. Will this keep the heat off the wood? I also have a small house fan now sitting beside the tank pointed up into the hood for ventilation.
    Rob
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    Upgrade in the works! Keep looking for an update.


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