Abstract: A filter unit, system and method for removing grease, oil and other particulates from air. The filter unit includes a housing having upstream and downstream walls and a cavity therebetween. The upstream wall has an entrance opening aligned with a downstream wall portion, and the downstream wall has first and second exit openings aligned with first and second upstream wall portions. A heat exchanger is disposed within the cavity and includes first and second upstream conduits within the entrance opening and first and second downstream conduits within the first and second exit opening. The entrance and exit openings are arranged to define S-shaped air flow paths through the housing between the entrance and exit openings, each of which flows around a downstream side of one of the upstream conduits then around an upstream side of one of the downstream conduits before exiting through one of the exit openings.

Abstract: Filter units and filtration systems, as well as methods of using such units and systems to remove particulates from air, for example, within a kitchen environment. Such a filter unit includes a heat exchanger within a housing, an access opening at a lateral end of the filter unit that defines a lateral narrowed section of the filter unit. The access opening provides access to headers of the heat exchanger through openings in enclosures that partially enclose ends of the headers. If one or more filter units are combined end-to-end to form a filtration system, a closure can be provided to removably close a through-passage formed by the access openings of two adjacent units.

Abstract: A filter unit, system and method for removing grease, oil and other particulates from air. The filter unit includes a housing having upstream and downstream walls and a cavity therebetween. The upstream wall has an entrance opening aligned with a downstream wall portion, and the downstream wall has first and second exit openings aligned with first and second upstream wall portions. A heat exchanger is disposed within the cavity and includes first and second upstream conduits within the entrance opening and first and second downstream conduits within the first and second exit opening. The entrance and exit openings are arranged to define S-shaped air flow paths through the housing between the entrance and exit openings, each of which flows around a downstream side of one of the upstream conduits then around an upstream side of one of the downstream conduits before exiting through one of the exit openings.

Abstract: A filter unit, system and method for removing grease, oil and other particulates from air, for example, in a kitchen environment. The filter unit includes a housing having an upstream side, an downstream side, and a cavity therebetween, a heat exchanger disposed within the cavity and comprising at least two tubes, at least one entrance aperture disposed on the upstream side of the housing and defined by at least one fin, at least one baffle disposed on the downstream side of the housing so as to be oppositely disposed from the at least one entrance aperture, and at least one exit aperture disposed on the downstream side of the housing adjacent the at least one baffle. The baffle and fin define at least one flow path through the housing and around the tubes.

Abstract: A heat exchanger assembly includes at least first and second coils adapted to contain a fluid therein and at least two support members securing the coils. Each of the first and second coils are individually formed of at least one tube including an inlet at an uppermost extent thereof and an outlet at a lowermost extent thereof and include a vertical column containing a plurality of horizontal rows and a plurality of bends at opposite ends of the horizontal rows and fluidically interconnecting the horizontal rows thereof in series to define a serpentine configuration. The first and second coils are adjacent each other and nested so that the horizontal rows of the first coil are parallel to the horizontal rows of the second coil and at least some of the horizontal rows of the first coil are disposed between adjacent pairs of the horizontal rows of the second coil.

Abstract: A filter unit, system and method for removing grease, oil and other particulates from air, for example, in a kitchen environment. The filter unit includes a housing having an upstream side, an downstream side, and a cavity therebetween, a heat exchanger disposed within the cavity and comprising at least two tubes, at least one entrance aperture disposed on the upstream side of the housing and defined by at least one fin, at least one baffle disposed on the downstream side of the housing so as to be oppositely disposed from the at least one entrance aperture, and at least one exit aperture disposed on the downstream side of the housing adjacent the at least one baffle. The baffle and fin define at least one flow path through the housing and around the tubes.

Abstract: A valve assembly is disclosed. The valve assembly includes a valve body having inlet and outlet openings. A central cavity is defined by the valve body. A movable poppet is positioned within the cavity. A plug closes the cavity and a spring extends between the rear end of the poppet and the plug. The rear end of the poppet defines a cylindrical recess and the valve body defines a drain opening adjacent the outlet. The cylindrical recess provides a fluid passage to the drain opening. The poppet is opened when the fluid pressure on the inlet side overcomes the force of the spring and is closed when the force of the spring is greater than the fluid pressure force on the front of the poppet.