Originally Posted by
APGLaser
Hey everyone, Im going to try and pack in every last bit of information I have that can help possibly answer my dilemma here.
I began working at the place im at about a year ago now. We have two lasers here..
1. Hurricane CO2 Laser Cutter 4' x 5' Table.
2. Trotec 300 Fiber Engraving laser
Over the winter we had a few issues with what seemed to be the acrylic gas's not exiting the building. Upon some reviewing I thought I had figured out the problem and everything began running smoothly, with no smells or complaints from anyone in the building. I used to work as an Auto Technician & Body Man so these smells really don't phase me but everyone else seems to get terrible headaches and are just miserable throughout the day when I have to cut something out on the Hurricane.
Our exhaust system is as followed (please bear in mind im just going by what I can physically see, i am no HVAC specialist or anything nor was i around when the system was installed)
I have some absolutely terrible sketch of the setup, i am attempting to draw it on paint so i can save it and post it here. so far im failing.
Every unit I have EVER seen has a simple. simple Tube > Fan > Outside setup and these people have zero problems. My boss went out of his way and bought a BOFA AD1500IQ Fume Extractor. The BOFA is ONLY hooked up to the Hurricane laser. The Trotec & Bofa however push air to the SAME exhaust pipe. it comes to a "T" and then one big pipe (12"+) take the gas to the upstairs unit.
The upstairs unit is a FANTECH SHR8004 Unit (Air Exchanger) the small room which this unit is contained it ABSOLUTELY REEKS of the acrylic gas
Whoever installed the EXHAUST and New-Air Intake seems to be a fool to me. On the side of our building you can see (2) vents. One being the intake, one the exhaust. To my knowledge all exhaust venting should be directly out of the roof. Now, we are sort-of in a valley so i feel like the airflow is coming over the building, pushing the Exhausted air from the top to the ground and being sucked back in by the new air. (however i could be completely wrong, thats why im here!)
Airflow numbers we are running.
The BOFA is pulling a solid 600CFM, which was recommended by the guys at BOFA to clear the Hurricane laser bed.
The FANTECH unit SAYS it pulls an average of 772CFM
Is it possible that throughout ALL this piping, we are losing so much CFM that the gases don't make it through the FANTECH and outside?
From back of the laser to the bofa there is roughly 36" of pipe the BOFA exhaust port to the Main Exhaust line is another 70" or so (mind you both of these have @ least 1 slight bend in them, they are the stretchy metal pipe.. i dont know the name, sorry) Mind you the TROTEC laser ALSO has a pipe thats roughly 70" bout only 4/5" diameter. now those two pieces of piping join into a roughly 4ft long section of what i think is 8-10" pipe, then from there it steps up to 12"+. The 12"+ Pipe is about 13 FEET long. From there it makes a 90 degree turn up, with another about 4/5 foot of square duct work it finally reachs the fan tech.
Im sorry if i was all over the place and confuse anyone, im confused as heck myself and just want to figure this out!
Thanks
-Jesse