Contractor for Hood Ventilation
We have kitchen range hoods in all the apartments in our three story brownstone. Unfortunately we are having a few problems. When the unit on the second floor is in use, some of the fumes come in through the hood in the kitchen on the third floor instead of exiting completely through the vent on…
We have kitchen range hoods in all the apartments in our three story brownstone. Unfortunately we are having a few problems. When the unit on the second floor is in use, some of the fumes come in through the hood in the kitchen on the third floor instead of exiting completely through the vent on the roof. So you can smell what the apartment below is cooking for dinner. It also doesn’t seem particularly safe.
We think we might need a fan of some kind installed on the roof where the vent opens in order to suck up the air more forcefully and prevent some of it from drifting in through the hood in the other apartment. Can anyone recommend someone who is expert in this kind of thing? I’m reluctant to hire just any old GC because it was our GC who installed these ducts/vents in the first place. I would prefer someone who has specific expertise with this type of ventilation.
Thanks a lot!
We recently had the same issue in our 4-unit co-op–we already had a fan on the roof but it wasn’t sufficient. We worked with All HVAC, 718-833-0148. They figured out what the max CFM the vent stack could take, which then determined what the CFM of each unit’s fant could be. But the main solution involved, as masterbuilder described above, installing backdraft dampers in each unit.
Sounds like a backdraft damper issue. Pull the mesh grease filter off and see if the butterfly flaps on the damper are stuck open. What about the fumes from the first floor? Why would those exhaust but not from the second? Usually I hold up a lightweight ribbon or piece of paper to a fan. If it is pulling air, then the ribbon should stick to the fan grille. Test each one.
There should be enough CFMs to exhaust each unit otherwise. If there are dampers in-line (meaning inside the concealed ductwork), one could have been installed the wrong way as well. There should be one located at the exhaust terminal at or near the roof.
Did the GC use smooth, rigid metal ducting (best)? Or flexible ducting? If flexible, the duct could be crimped. Also, only certain kinds of duct tape are actually rated for duct work, and over time the wrong tape will deteriorate and the ducting can come loose.
Check for simple issues first. Also see if you can add charcoal filters to the range hoods. Many have that option these days. The smell of food cooking is not hazardous – it’s grease build up that could cause a fire.
If you do decide to add a unit, take a look at Panasonic fans.
George Fraschietti, Electric Motors and Pumps, on Carroll Street