Rooftop Barometric Relief
Rooftop Barometric Relief
(OP)
We have a constant volume hvac system utilizing package rooftop equipment with a supply fan, no return fan, and an economizer. When the unit was installed the barometric relief was missing(not installed). The unit is set up to supply a minimum amount of outside air for ventilation. The space is over pressurized when the unit is running. No provision was made to relieve pressure. Will adding the barometric relief dampers to the units relieve pressure from the building on a "non-economizer" day or does the relief only operate when the unit is on 100% OA (economizer mode)? Thank you very much for any reply.





RE: Rooftop Barometric Relief
As the economiser opens, the space would pressurise to a higher equilibrium, so a barometric damper will be forced open to compensate. This may open gradually in proportion to the outdoor air, or flap open with a on/off economiser.
RE: Rooftop Barometric Relief
So now your relief air can't get out. With this kind of unit you have to duct a relief duct off of the return, put in a relief damper, and duct to a separate opening thru the roof.
RE: Rooftop Barometric Relief
RE: Rooftop Barometric Relief
RE: Rooftop Barometric Relief
RE: Rooftop Barometric Relief