Dealing with dangerous vapors that can corrode equipment is part of designing any exhaust mechanical system for a fume hood. The design of the component is essentially two cylinders, one inside of another. Sponsored Forums Private Forums Authors. Unfortunately my roof boot didnt fare so well.
The no-loss stackhead shown is only one type. The two cylinders are welded together with spacers so the rain water has plenty of room to fall between the two cylinders and onto the roof. It is an inexpensive solution to keep your fume hood dry while still maintaining an open space to vertically exhaust contaminated air. A Zero Pressure Weathercap can save the day; any fume hood mechanical system without one is incomplete.
Whether you are installing a new roaster, or just need to fix an old or troubling installation, a no-loss stackhead will help your equipment run better, your coffee taste better and your neighbors stay happier. Being located in Florida, we get plenty of rain to put this to the test. Newer Post Older Post Home. The secondary reason for using a no-loss stackhead has to do with pollution control--more specifically, with reducing your chances of getting nuisance complaints caused by smoke and smell emanating from your stack.
No-loss stackheads are designed to keep rain out of a stack by using the principle that rain does not fall straight down. The primary reason that no-loss stackheads are important to coffee roasters is that they are, simply, the correct stack termination for equipment with positive pressure exhausts like coffee roasters.
Please use a valid email address to subscribe. Google Sponsor Google Sponsor. I just tested this in a downpour and I was looking straight up the tube and just getting a tiny bit of random splash mist hitting my eye while cars were floating down the street.
Therefore the rain follows the path of least resistance to the outside of the duct where there is near zero pressure and near zero velocity. I figured as much but I was unable to find a storm collar or a cover boot at the home store, so I guess I'm off to the roofing store to find that finishing fix.
This is due to the increased back pressure caused by higher-velocity and higher-volume exhausts. But what about the rain? Perhaps I should have used PVC for the riser.