cooling fan for Lumenarc III?

[labragg1]

Ok, so I placed my order today for two Lumenarc 3's with the A/C option. After talking with Luke at Pacific Garden Supply where I placed the order, he recommended to use a Centrifugal Duct Fan with the A/C option. The fans run around $140 for the smallest Fantech model, but he said that with only two lights I really didn't need one that large. He said that these are normally used for 3 to 4 light systems.
He mentioned Home Depot or Lowes--but after calling them they don't seem to know what I'm talking about.

Anybody got any suggestions? Is there something a little cheaper that will work well? Anybody using the A/C option with LA3's?

Thanks

[Ceak]

tagging along, also interested...

[labragg1]

Surely somebody has some input on this???????????????

[newty]

Ever thought about using computer fans? That is what I am using over my sump at the moment.

Newty

[labragg1]

I've thought of using pc fans, but I don't know how well they would do with around 4 or 5 feet of ductwork. Also attaching pc fans to ductwork may be a challenge.

[newty]

Ah, I see. What about bathroom ventilation fans?

Newty

[labragg1]

Actually, I was thinking about that, but I wasn't sure how much pressure/suction they had. Basically when I talked Luke at PGS, he said that the A/C option works by the system being sealed. When you by the A/C option for the LAIII's, it also includes the glass shield. He said that this allows the pendent to be sealed. The centrifugal fans are designed to work with a sealed system. This creates a very high suction thus pulling any heat completely out of the hood in seconds. He said that this basically results in virtually no heat getting to the water. It would also allow you to lower the lights much closer to the water than normal. The Fantech model fan he had was around 100cfm. He said that with only two pendents, I could get by with a smaller fan. The problem is I can't find a centrifugal fan that is under $100.
I have also been looking at the in-line fans at Home Depot that are designed for ductwork, but again, I don't know if they would be powerful enough to create the suction needed.
I will be talking with Luke at PGS again this afternoon, so hopefully I can get some more recommendations of what will work.

[Ceak]

labragg please keep us posted on the issue, I am planning to get the A/C option asweel so yuor infot will be very valuable to me.

thanks

[newty]

Actually, I was thinking about that, but I wasn't sure how much pressure/suction they had. Basically when I talked Luke at PGS, he said that the A/C option works by the system being sealed. When you by the A/C option for the LAIII's, it also includes the glass shield. He said that this allows the pendent to be sealed. The centrifugal fans are designed to work with a sealed system. This creates a very high suction thus pulling any heat completely out of the hood in seconds. He said that this basically results in virtually no heat getting to the water. It would also allow you to lower the lights much closer to the water than normal. The Fantech model fan he had was around 100cfm. He said that with only two pendents, I could get by with a smaller fan. The problem is I can't find a centrifugal fan that is under $100.

I did not know that it would be a completely sealed system. I cannot think of any other cheap fans that would work in your case. Hope it works out for you.

Newty

[labragg1]

Well--I just got of the phone with PGS a little while ago, and it looks like there might be a few options that would work. He said that naturally a centrifugal fan would be the ideal thing, but not the most cost effective. He said that a regular inline duct fan may work fine for just two units. I'm headed to Home Depot tonight to see what they have, but here's what I'm looking at--
http://www.smarthome.com/3016.html
At only $27--I could put one of them on each LAIII and still come out at almost half the cost of a centrifugal fan. They are supposed to move around 80CFM, so hopefully that will be enough.
As soon as I receive the LAIII's, I'm going to do some testing with a few different fans and see what works the best. I figure that with only a few feet at most of ductwork, these fans should do the trick--but we'll see.
I'll keep you posted!!! Now I just have to wait for UPS.............

[dougchambers]

That's the fan I plan to use. Where are you going to pull your make-up air from? I'm assuming that one of the two (2) 4-in ducts is for fresh air return...

[labragg1]

The second duct is to link to another LAIII. When I talked to PGS, he didn't say anything about having to have any fresh air return. He said that basically the seems and rivet joints of the reflector are not totally air tight. He said that I would be able to feel the fan pulling air through every little seem and cranny in the reflector.
He didn't seem to think that I would even need to have any other fans or ventilation in the canopy. I will probably go ahead and have one descent sized fan moving air in the canopy anyway, though.

[labragg1]

I picked up one of the 4" inline fans at HD tonight--only $25. I'm looking forward to see how well it will work. I also picked up some 4" rigid ductwork as PGS said the air flow was a little better than with the flexible stuff. UPS is supposed to deliver sometime middle of next week!!!

[TheFlyingTang]

Just go to Radio Shack and pick up a 120 VAC 4" diameter fan. Use a 4" hole saw to make a cut out of the back of the hood and hard wire it.

I have two Lumanarcs running 2- 250w MH and I leave the fan is always running. I do this to eliminate condensation problems when the lights are off.

Works great and it keeps the inside of my hood clean and dry.

[labragg1]

Are you referring to cutting a 4" hole in the canopy or the actuall reflector? If you mean in the reflector--wouldn't you be losing a 4" area of reflective material? Also I would wander if the plastic fan would end up getting soft or melting over the long term with it being so close to the bulb? Not sure about that.
I will also be running 400mh's instead of 250's--so I may have a little more heat to deal with than you.
Thanks for the input!!!

[labragg1]

For those of you interested in the results of the testing I did with the A/C option--look here: http://www.reefcentral.com/forums/showthread.php?s=&threadid=832513

I posted some pics and results in my tank thread as I was having a hard time keeping up with multiple threads. Sorry for the delay in results.