Welcome to BigScreenBiz.com

Does anyone have a heat exchanger connected to their lamphouse exhaust? Is this even do-able? Many of you tropical folk probably don't even think about heating, but up in the frozen North winters be mighty cold. -40C with the windchill is a common temperature....skin freezes in under a minute...winds of 100k.....uh, you get the picture.

I was thinking if I connect a heat exchanger to the exhaust pipe, I could blow the heat back into the booth, office, lobby area. Would something like this comprimise the vent system for the bulbs?

The King

---

'The King is only as wise as his Jester'

In many jurisdictions lamphouses must be directly vented to the outside. No other diversions are allowed.

[This message has been edited by Ken Layton (edited October 03, 2003).]

I think I remember a post either here or on Film-Tech about this.
If I recall correctly there is an issue with small traces of (or possibility of) harmful gases that could be in the exhaust from the lamphouse, which is why it has to be vented to the outside.

Tony

I'm talking about a type of 'heat recovery' unit. some homes have an air exchanger to draw in fresh outside air. the exhaust air passes through some sort of plate or duct that warms the incoming air, but never actually mixes fresh and exhaust air. I'd like to put the hot air from the lamphouse to good use, but I really don't want to breathe in tons of ozone.

The King

---

'The King is only as wise as his Jester'

JOE <> The problem here is the fact that you probably won't be producing enough heat to justify the cost of a heat exchanger, in relation to how much heat you can gain from it... Depending on your lamp size, the heat it produces (at the exhaust) is about equivalent to a good sized hair blow dryer, unless you have something in the range of 4k watts, or larger... Since the heat exchanger isn't nearly 100% efficient, you can recover only part of that, and I doubt that what you will recover will justify the cost of recovering it... Now, I am going to make a confession, and you gotta swear you won't rat me out... I built my own lamphouse conversions, and the last item on the lamphouse is a fairly quiet blower which normally exhausts the lamphouse into a gravity/draft system dumping into outside atmosphere... In cold weather I loosen the clamps at the top of the flex connecting hoses, and install plugs in the gravity duct which have a bracket to support the exhaust flex, and dump all the heat into the booth... I utilize 100% of the heat from the lamps... Is this safe?... Well, the booth is fireproof, having been built back in the nitrate days (I finally did away with the fire drops about 20 years ago, when the state finally admitted they weren't necessary any longer) so there is no fire danger (which is questionable IF there is, under ANY circumstance, with xenon)... The lamps are supposidly ozone free, and it hasn't been that long ago that ozone producing lamps were sold to reduce bacterial contaminations and odors, and touted as healthful... Every other week something that has been "good" for you, is NOW declared "bad" for you, then reversed again, so what can you believe... I suspect that even IF there is a small amount of ozone produced, it isn't that unhealthy... Besides, I am a 3 pack-a-day smoker, and have worked with asbestos based brake linings, and clutch facings, hydrocarbon based carburator cleaner, fiberglass, lacquer paints, leaded paint, leaded gasoline, formaldehyde and hundreds of other things which are NOW declared to be health hazzards... To be sure, something will eventually kill me, but I doubt that it will be the short time exposure to the exhaust from a Xenon lamphouse... In the meantime, I supplement the heat in my booth with some "free" heat for a couple of months a year, and it feels damned good!...

Ozone free lamps don't produce much ozone but the spark gap in many ignitors do
Ozone will bleach lungs and even though it is a disenfectant (kills virus's and bacteria on contact) so is Javex and I doubt you would want a shot of it on the rocks either
Also the air exhausted from a lamphouse is usually very dry and will just add to any static issues you might have in the booth

OK, in a 10 screen, with a common projection booth, operating 12 hours per day, I tend to agree with you... In a single screen operating 4 to 5 hours per day, I don't... There aren't that many ignitor pulses involved (unless you have serious lamp/supply problems)... Every time you flip ANY light switch, you produce a small electrical discharge which also produces a very small amount of Ozone... I run 6k reels, and humidity/stactic electricity has never been a problem, but there is a metal cake pan full of water sitting on top of the radiator in the booth, just for comfort's sake in cold weather... Would I deliberately inhale large amounts of Ozone?... No sooner than I would inhale acid fumes, dust, or any number of other potentially toxic stuff, but I'd bet the family jewels that the Ozone levels in my booth with the Xenon exhaust disconnected are considerably lower than what you would find in the typical power generating plant, or anywhere near a decent sized transformer bank... Nobody seeks out dangerous envoirnments, but common sense has to play a role: you can't spend your life worrying about the Methane content in cow farts... It all boils down to the parts per million...

#1 make sure that your building is well insulated, your heat system in perfect tune, thermostats watched and respected, and that doors-windows-etc. are well sealed.
#2 a heating person could tell you what you stand to gain in hard #'s but I'll bet it isn't worth it.

My lease is heat included so I don't think about this too much.

I'm more concerned how to keep a booth cool!

---

Michael Hurley
Impresario