Abstract: A water heating apparatus having structure for recovering sensible and latent heat from flue gases generated in a heater thereof and transferring the heat to water to be heated. The apparatus has a closed circuit for liquid, such as water, in which are positioned two heat exchangers. One of the heat exchangers is positioned in the heater of the apparatus for transferring heat from a burner of the heater to liquid in the closed circuit. The other heat exchanger is positioned in a water pass-through system to heat the water therein. The apparatus has an air pass-through system for carrying flue gases from the heater out an exhaust pipe. The flue gases travel through a third heat exchanger positioned in the water pass-through system whereby sensible and latent heat from the flue gases are transferred to water in the water pass-through system, further heating the water therein.

Abstract: A fireplace adapted to heat multiple heating zones of a building, controlled by a control circuit which adjusts the heat input to the fireplace, airflow through the fireplace and ducting of the airflow to the various zones individually in response to a call for heat by thermostats in the zones. The fireplace may also be adapted to provide cooled or circulated air to the zones and may also serve to provide heating to the zones in the event of an electrical power outage. The fireplace is provided with a cabinet having ducts through which air is conveyed by use of a fan to a tube-type heat exchanger, the heat exchanger also in communication with the hot flue gases exiting the combustion chamber of the fireplace. The air heated by the heat exchanger is conveyed to a multitude of fireplace outlets, each of which is provided with a damper which regulates the airflow through the outlet to one of the zones to be heated, depending on whether that zone calls for heat through its thermostat.

Abstract: A burner for the combustion of fuel and air in an industrial furnace, for use in connection with preheated combustion air, is provided having an equal number of evenly spaced air jets and fuel jets. The air jets and fuel jets are discharged so that they initially diverge away from one another, but eventually, the fuel jets are entrained by the air jets. During the course of their trajectories, before meeting, the air jets and fuel jets entrain resident furnace gases which results in heavy dilution of the fuel and air before combustion. The dilution causes off-stoichiometric combustion conditions and results in a lower flame temperature. This is similar in effect to external flue gas recirculation. As well, the fuel jets undergo pyrolysis in the course of their trajectories before entrainment occurs. This creates a reducing zone in which the NOx in the resident furnace gases being entrained is reduced, in part, back to molecular nitrogen.

Abstract: A range for sealed combustion of a gaseous fuel has a hob assembly and an oven. The hob assembly comprises a glass ceramic cooking surface sealed to a support box and one or more burners. The hob assembly and oven are connected to a fresh air intake/exhaust manifold, such that there is no air exchange between the range and the room in which it is located. Narrow heat transfer passageways are defined between the cooking surface and an internal surface around each burner.

Abstract: A method of forming a burner for a gaseous mixture of fuel and an oxidant mixes a random mix of refactory fibers, the fibers being predominantly alumina and silica, and then forms a burner body from the fiber mix. Passageways are then formed in the burner body by perforating the burner body with pins. This is achieved by providing comb assemblies each having a plurality of pins, which are pressed into the body from either side and then removed, and the body is then indexed for further sets of holes to be formed. The burner body can be treated with colloidal silica and subsequently baked to bond and preshrink the fibers, both before and after the forming of ports or passageways.

Abstract: There is provided a range for sealed combustion of a gaseous fuel comprising a hob assembly and an oven. The hob assembly comprises a glass ceramic cooking surface sealed to a support box and one or more burners. The hob assembly and oven are connected to a fresh air intake/exhaust manifold, such that there is no air exchange between the range and the room in which it is located.

Abstract: A sealed combustion, low profile gas-fired baseboard heater has a heat exchanger which is U-shaped, and which has upper and lower horizontal sections. Appropriate inlets are provided for air and combustion gas, and a gas valve. The air inlet may be coaxial with an exhaust for combustion gases. The heater may include a combustion blower, in which case the heat exchanger can include fins and other features to improve heat transfer. A natural draft version includes a larger bore tubular heat exchanger. Ignition can be by way of a pilot. Alternatively, a hot surface igniter, with safety lockout-timing device, can be used.

Abstract: A heat exchanger has two regenerative beds and two valves connected to the beds for controlling the flow through them. Each valve has two ports connected to the beds and two other ports. The valves are mechanically linked and actuated together. The valves serve to alternate two gas flows between the two beds, to effect heat and moisture transfer between the gas flows. Each valve has two valve members mounted on a common valve shaft controlling the connections between its ports.

Abstract: A heating and ventilating system has a space heating device, in which heat is generated by combustion of a fuel, and which heats air for a building. A heat exchanger has one side through which exhaust air from the building flows to the exterior. Through the other side of the heat exchanger, fresh, makeup air for the building is supplied, and this may pass through the heater. An exhaust conduit from the heater, for combustion products, opens into the exhaust air line connected to the one side of the heat exchanger. This enables heat to be extracted from air leaving the building and further heat to be extracted from the combustion products, this heat being transferred to the incoming air in the heat exchanger.

Abstract: A compact apparatus for residential, commercial and industrial airconditioning involving balanced heat recovery ventilation, heating, humidification, dehumidification, cooling and air filtration comprises two treatment vessels, each containing a compact packed bed of a solid sorbent material, a heater and a solid heat exchanging material, a 4-way valve for switching the flows of the exhausted stale air and the incoming fresh air between the two treatment vessels to permit a cyclic countercurrent short cycle operation of the packed beds to achieve efficient transfer of heat and moisture between the two air streams. The two treatment vessels are complemented with a combustor, a direct evaporative cooler and a solid state process controler permitting operation of the apparatus to provide the required services during the winter-heating season, summer-cooling season and the rest of the year-ventilation season to maintain comfort in the air conditioned space.

Abstract: A water heater tank having a vertical, open-ended flue formed by a cylindrical wall extending therethrough, a metal annulus formed at the bottom of the flue wall, said annulus being continuously affixed to or integral with the bottom of the flue wall for effective heat transfer from the annulus to the flue wall, said annulus having an upturned lip on the inner side thereof such that said annulus will collect and retain condensate forming on the flue wall for subsequent evaporation of said condensate.

Abstract: Improved furnaces are described in which secondary and tertiary heat exchanges are incorporated into new and existing hot-air furnace systems for controlled cooling of hot combustion products by co-current and countercurrent heat exchanges. Hot combustion products are cooled to a temperature at which latent heat of water vapor contained in combustion gases are substantially recovered.In one embodiment of our invention, a secondary heat exchanger comprises inter alia a closed hollow annular drum concentric with and spaced from a cylindrical combustion chamber, said annular drum having an upper annulus preferably filled with randomly packed refractory material.A second embodiment of our invention comprises a closed double-annuli drum heat exchanger concentric with and spaced from a cylindrical combustion chamber.Finned tube or thermosiphon heat exchangers can be arranged sequentially with the primary heat exchanger combustion chamber to function as a secondary heat exchanger or as a tertiary heat exchanger.

Abstract: A flue heat exchanger particularly adapted for use in a water heater tank comprising a plurality of segments of a metallic or non-metallic non-friable refractory material randomly packed within a flue. Rounded metallic sections of steel pipe or copper tubing having a length not less than one-half and not more than twice the diameter of said pipe or tubing are preferred.

Abstract: A method and apparatus for providing a continuous indication of the interior condition of a water heater tank are shown herein. Iron interior surface of water heater tank is normally protected from corrosion by cathodic protection with the provision of a sacrificial anode element made of a highly anodic metal. A zinc probe is incorporated in the water heater tank such that the potential measured between the zinc probe and the iron interior surface indicates the condition of the sacrificial anode element thus providing an indication of the effectiveness of the cathodic protection. The zinc probe may be conveniently incorporated in the drain cork of the water heater tank.