Patent Application
20170198941
The invention relates to fresh air ventilation for a building. More specifically, the invention relates to fresh air ventilation for a building through utilization of the heating system of the building, wherein the heating system includes a blower fan to expel exhaust gases from the furnace combustion chamber and wherein combustion air is provided from outside the building through a pipe or other dedicated ductwork.
Prior to the introduction of high efficiency furnaces, typical heating systems incorporated a furnace which was designed to use air from inside the building for combustion, and due to the higher heat of the exhaust, the gases passed upward through a chimney to the outside of the building. With this type of furnace design, replacement air is provided through leaks around windows and doors and when opening the doors to enter the building.
Contemporary buildings are designed to be more airtight to retain heat energy by eliminating drafts and air leakage. As such, there is a need to provide adequate ventilation into a building to offset contaminated air generated by chemicals and pollution inherent in the indoor environment. These pollutants include household cleaning chemicals, outgases from laminated plywood and particle board construction materials as well as plastic products such as carpeting and other flooring materials. As such, a need has been established to provide fresh external air to be included in the air contained in a building.
In addition to tighter building construction, energy efficiency standards require manufacturers to produce furnaces that convert as much fuel energy as possible into heat to be used in a building. With most of the fuel energy being converted within the furnace, the cooler exhaust gases cannot easily flow out of the chimney through convection. For this reason, high efficiency furnace manufacturers have included a blower fan to expel exhaust gases from the furnace and to draw in combustion air, in most cases, from outside the building.
Modern buildings typically incorporate high efficiency furnaces to supply heat. Most such furnaces include high efficiency heat exchangers which have the effect of reducing the temperature of the gases exhausted from the furnace combustion chamber. Because of the low temperature of the exhaust gases, these types of furnaces require a fan to remove the exhaust gases from the furnace to the exterior of the building, an action which is typically accomplished through a PVC pipe. Combustion air can be provided from inside the building but is typically drawn by the combustion fan from outside the building into the furnace through a second PVC pipe. In operation, air is drawn into the furnace combustion chamber, travels through the heat exchanger or exchangers and is ultimately exhausted through a PVC pipe to the outside of the building through the action of the exhaust fan included in the furnace.
To provide fresh air, many buildings include ventilation systems featuring ‘heat recovery ventilators’ which are units designed to recover heat energy through exchange of air from inside the building with air from outside the building by passing the air through a radiator type heat exchanger, an action designed to heat the air coming into the building with the radiant temperature of the air leaving the building as shown in U.S. Pat. No. 7,073,566, U.S. Pat. No. 6,450,244 and U.S. Pat. No. 6,575,228. These systems typically are stand alone designs that do not require action from the furnace or air conditioner to operate. Because of their exclusive function, these systems can be quite costly to purchase and install. These types of heat recovery ventilator systems do not utilize the furnace combustion fan as a ventilation component to expel interior air from the building.
As a solution to this need for an efficient and inexpensive ventilation system, the present invention provides fresh air introduction into a building while exhausting stale air from the building in a simple and cost effective manner.
The present invention provides interior air management in a building by allowing outside ‘fresh’ air to be brought into the building in the most efficient manner. The present invention may also have the effect of reducing humidity in a building when the system is in the heating mode, while also balancing air pressure between the exterior and interior atmosphere.
The present invention describes a ventilation system which includes:
In relation to the above descriptions, incoming air for the furnace combustion chamber can travel via 2 pathways or modes. In a first mode, air is drawn into the furnace in a typical manner, that being through a pipe from outside the building, and, in the case of the present invention, through a manifold, into the combustion chamber. Alternately in a second mode, air from inside the building is drawn into the furnace through the first manifold, and in a preferred embodiment, replacement air is provided through a second manifold wherein air is drawn from outside the building from an area remote from the furnace exhaust, into the interior of the building preferably through the cold air return ductwork of the furnace. In this second mode, combustion air is drawn from the interior of the building from an area near the manifold or through special ductwork designed to pull air from a remote location inside the building. In a third, combination mode, combustion air is drawn from both the interior of the building and the exterior of the building through a first manifold thereby blending or mixing various amounts of outside air with air from inside the building which is then drawn into the furnace combustion chamber, while in a preferred embodiment and in cooperation with a separate second manifold, varying amounts of outside air enters the building preferably through the cold air return ductwork of the building thereby blending with the interior air returning to the furnace. Dampers may be required to control air speed and air volume appropriate for air entering the cold air return ductwork and to prevent air from entering the building when the system is off or when fresh air is not desired. In a further embodiment, interior air could be siphoned off the cold air return ductwork of the building heating/ventilation system from a point ‘upstream’ from where fresh exterior air is introduced into the cold air return ductwork.
It should also be noted that replacement air could be provided through cracks and gaps in the building or through operation of windows and doors in the same manner as incorporated in non high-efficiency heating systems. In this embodiment, a second manifold to allow air into the building would not be utilized.
In a further embodiment, fresh air could be introduced into the building while the furnace is off and a ventilation or air conditioning fan is operating. Interior air exchange could be accomplished by operating the combustion blower fan of the heating system to exhaust interior air, with the gate within the first manifold correctly positioned and the combustion burner not operating and thereby not producing heat, while fresh air would be introduced into the building through the second manifold, preferably by blending exterior air into the air included in the cold air return ductwork through drawing action of the blower motor of the furnace/air conditioning system. In a further embodiment, a separate fan could be used to provide air movement to the outside of the building when the system is in the cooling or ventilation mode. Additional electric fans may also be used to assist in air movement.
Regarding the present invention, it should be noted that the air replacement process described could include a heat transfer element or heat recovery ventilator system such as a radiator type heat exchanger, wherein incoming air would be preheated with the radiant temperature of the air from inside the building or by the air being exhausted to the outside of the building.
Operation of gates which control the direction of the fresh air and/or combustion air could be controlled manually, or in a preferred embodiment, by an electronic control system in coordination with electric motors or solenoids designed to control the action of the movable air gates which could be operated in coordination with each other or independently from each other to optimize the desired air movements. In a non-limiting embodiment, the manifold controls could be included within or near the thermostat controls for the building, with possible air supply choices being ‘fresh’ to include outside air or ‘recirculate’ to recycle the existing interior air. From an operational perspective, the air choices are similar to choices available in automobile ventilation systems.
The present invention would be used with a high efficiency furnace that includes forced air ductwork or could be used with a high efficiency furnace wherein a separate ventilation ductwork system is utilized. This type of furnace and separate ductwork could be incorporated when using a hot water radiant heating system or other heating system which utilizes an exhaust fan for the combustion burner and wherein ventilation and/or cooling is provided through a separate ductwork system. Additional modifications and additions could be incorporated without deviating from the scope of the invention.
The accompanying drawings are meant to describe a non-limiting design for manifolds which could be used to facilitate the air transfers previously described. The views in the figures are included as partial views of the manifolds in that the upper cover for the manifolds and control elements for the movable air control gates are not fully described. As a visual aid, arrows shown on the drawings depict air flows into and out of the manifolds and the cold air return ductwork of the building. The drawings describe the method and system in plan view showing the manifolds, each with a plurality of ports, movable air control gates and a representation of the manual or electronic control mechanisms used to control the gates.
As shown in FIGS. (1-3), various air flows are directed through action of special manifolds (10 & 12) which are designed to facilitate the direction of the air flows through adjustment of movable air control gates (20 & 22).
In reference to FIGS. (1-3) , first manifold (10) comprises exterior air inlet port (40), furnace combustion air outlet port (30), and interior air inlet port (50) which directs air from inside of the building into the manifold (10). Within manifold (10), a movable air control gate (20) is located and designed in such manner as to direct the air from inside or outside the building to the combustion air outlet port (30) while also creating a substantial barrier to seal off the undesired air pathways and eliminate or control air leakage between the ports during use. In addition, second manifold (12) comprises exterior air inlet port (60) and outlet port (70) and movable air gate (22) which is designed to control the air traveling into the building preferably through the cold air return ductwork (80). In standard mode and as best shown in
In operation, manifolds (10 & 12), including corresponding movable air control gates (20 & 22), will operate in 2 basic modes. In a first mode as shown in FIG. (1), outside air enters the manifold through fresh air inlet port (40) and continues through the manifold to furnace combustion burner outlet port (30). This mode allows the furnace combustion air to be supplied from outside the building in the same manner as existing high efficiency furnace designs. In a second mode, through repositioning of the movable air control gate (20) located in first manifold (10) and as shown in FIG. (2), air from the interior of the building will be directed to the furnace combustion burner outlet port (30). In a preferred embodiment, replacement air will be introduced into the building through action of the air control gate (22) located in second manifold (12), through inlet port (60) and outlet port (70) and preferably blended into air returning to the furnace through the cold air return ductwork (80). In this manner, air from outside the building is introduced into the building while air from inside the building is exhausted through the fan induced exhaust of the furnace combustion burner.
The non-limiting drawings of manifolds (10 & 12) shown in plan view in FIGS. (1-3) include a representation of control mechanisms (A & B) which will operate gates (20 & 22) either remotely and/or through automatic controls. In operation as shown in FIGS. (1-3), movable air control gates (20 & 22) located inside manifolds (10 & 12) would be operated by control mechanisms (A & B) and will, in a first embodiment, and as shown in FIG. (1) be positioned to allow outside air to be directed to the furnace combustion burner outlet port (30) wherein the air is further directed to the combustion fan of the furnace while air entering the second manifold (12) is prevented by air control gate (22) from introduction into the cold air return (80). In a second embodiment, as best shown in
In a third embodiment and as shown in FIG. (3), the adjustable air control gates (20 & 22) located in manifolds (10 & 12) could be moved by control mechanisms (A & B) to a position which would allow a variable amount of exterior air and interior air to be supplied to the furnace combustion burner outlet port (30) and then to the furnace combustion fan and ultimately to the exterior of the building while, in coordination and in a preferred embodiment, a variable amount of fresh air to enter through second manifold (12) via inlet port (60) to outlet port (70) and thereby blend with air present in the cold air return ductwork (80) of the building. The movable air control gates (20 & 22), through action of control mechanisms (A & B), could operate in an independent manner, allowing interior air to exit and, by positioning air control gate (22) in manifold (12), allow an optimum amount of exterior air to enter the building, or if necessary, to block air from entering.
In a fourth, non-preferred embodiment, furnace combustion air could be drawn from inside the building without inclusion of the second manifold (12), with replacement air being provided through cracks around windows and doors in addition to air entering the building during use of the windows and doors. In such embodiment, only first manifold (10) would be utilized and would operate in the same manner as shown in the FIGS. (1-3).
In a preferred but not limiting embodiment, movable air control gates (20 & 22) will be designed to be able to independently seal off the air channels to the exterior when the heating system is not in use. Separate dampers may also be included in the pipe or pipes connecting the manifold to the cold air return ductwork to allow adjustment of the amount of fresh air entering the building and thereby blending with the inside air returning to the furnace. In addition, supplemental air filters and cleaners could be included in the air inlet system prior to the air entering the cold air return ductwork (80).
In operation, movable air control gates (20 & 22) are positioned through mechanical means which are in turn controlled through manual, electromechanical, pneumatic, or other means and are represented by (A & B) in the drawings to position the gates (20 & 22) to allow either air from outside the building or air from inside the building to be directed to the furnace combustion burner, while in cooperation, air from outside the building can be blocked or allowed to enter the building through second manifold (12). It should be noted that control means (A & B) could operate air gates (20 & 22) independently or in coordination with each other to optimize air transfer while also being designed to prevent inclusion of exterior air into the building when the heating system is not in operation.
In a preferred but not limiting embodiment, a user may operate a physical or electronic ‘switch’, possibly incorporated into the thermostat located within the living quarters of the building, which will send a signal to the control mechanisms represented as (A & B) which operate the movable air control gates (20 & 22) located within the manifolds (10 & 12). The switch could have positions which represent ‘fresh’ which would open the manifolds to allow all or a variable amount of exterior air into the building through the cold air return, or ‘recirculate’ which would have the effect of recycling the interior air and wherein no exterior air is added to the interior of the building. The action of switching the direction of the air flows may be manually chosen or it could be automatically controlled, possibly based on humidity level, barometric pressure, or could be time sensitive to position the manifolds (20 & 22) to allow inclusion of fresh air at selected time intervals or could be determined by other parameters. Settings which would allow variable amounts of fresh air into the building through the second manifold (12) without the operation of the first manifold (10) could also be incorporated without deviating from the scope of the invention.
This application claims the benefit of Provisional Patent Application 62/125,850 dated Feb. 2, 2015, Confirmation No. 4151.
