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Author Topic: Christie Lamphouse Ventilation Question Gary Crawford Expert Film Handler Posts: 200 From: Neptune NJ USA Registered: Nov 2003 posted 08-22-2006 12:14 PM                     Christie Xenolite K30 lamphouses, late 1960s vintage. Looking to replace the old roof-mounted squirrel cage exhaust blower, used back in the days of arc lamps, with in-line fans like you have in forced-air heating systems. I have the manuals from the Christies but nowhere does it list a recommended CFM / air flow requirement. Do any of you folks have this info? Thanks!  |  IP: Logged Dustin Mitchell Phenomenal Film Handler Posts: 1865 From: Mondovi, WI, USA Registered: Mar 2000 posted 08-22-2006 12:44 PM                     The amount of airflow required will depend on the size of your lamp. I've heard on this site the rule of thumb 'if it can suck the Sunday paper up the stack then you have enough airflow.'  |  IP: Logged Monte L Fullmer Film God Posts: 8367 From: Nampa, Idaho, USA Registered: Nov 2004 posted 08-22-2006 12:44 PM                     Definitely - Good luck - Monte  |  IP: Logged Gary Crawford Expert Film Handler Posts: 200 From: Neptune NJ USA Registered: Nov 2003 posted 08-22-2006 12:53 PM                     If by size you mean wattage...2000. If you mean the size of the lamphouse...oh, I'd say...about a cubit-and-three-quarters long, a cubit wide and a cubit tall, give or take... I've seen some posts in here that claim improper CFM can make the lamp run too hot, or too cool, and the bulb life will suffer, etc etc etc, so was just wondering if anyone had some historic Christie ventilation info that might be important. Don't think the Sunday paper will fit into the lamphouse, and if it did fit, the heat of the bulb would set in on fire, and all the soot and ashes from the newsprint, and the charred wiring in the lamp, and the theater owner whining and crying...  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 08-22-2006 02:13 PM                        Minimum of 500 cfm at the stack, with doors closed and all stack back pressure accounted for. 1000 cfm is better. I do not recommend in line blowers. The squirrel cage blower should be located above the projector on the underside of the roof. You are correct in removing roof-mounted units due to their expense and failure rate. This has been covered fully within the last 90 days. Louis  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 08-22-2006 02:27 PM                     I use a Dayton 985 cfm which is the smallest blower I will install and if you run 3kw or larger more like 1500 cfm. Measured with doors closed but dowser open! Mark  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 08-22-2006 05:42 PM                     Agreed, I have yet to find an issue of "overcooling", and I can proudly report in excess of a YEAR's worth of grind house running on one 6K lamp with 1500CFM exhaust. (Christie lamphouses+Christie bulbs, of course) The more the better. The opening on the top of your lamphouse will ultimately be the restrictive factor, so put in the biggest mother of a fan you can. PS - your subject title sucks as badly as that little fan on top of your old console did. Please change it to reflect what we are really talking about. Christie makes more than this one product, ya know.  |  IP: Logged Gary Crawford Expert Film Handler Posts: 200 From: Neptune NJ USA Registered: Nov 2003 posted 08-23-2006 12:49 PM                     Title fixed. 1000 CFM, better 1500, and in-line fans not recommended. Thanks guys.  |  IP: Logged John Pytlak Film God Posts: 9987 From: Rochester, NY 14650-1922 Registered: Jan 2000 posted 08-25-2006 10:44 AM                        Although you want to be sure that the lamphouse blower has sufficient airflow to properly cool the lamp, Osram cautions against overcooling a lamp, or cooling it unevenly, as it creates turbulance inside the lamp, leading to an unstable arc plasma: http://ecom.mysylvania.com/miniapps/FileNet2/EngineeringBulletins/ENGR_BLTN11.pdf quote: See page 25 about "Excessive Cooling"  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 08-25-2006 04:30 PM                        I, too, have heard that from Osram. I have NEVER found it to be true in actual use. (TWO Sunday newspapers worth is about right...hold on to your cleaning rag!!) Louis  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 08-25-2006 04:35 PM                     Actually I have had occasion of over cooled lamps several times that cause premature unstability  |  IP: Logged

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