Abstract: A furnace for heating air includes a primary heat exchanger and a secondary heat exchanger to transfer heat from a flow of hot gases, the secondary heat exchanger being arranged downstream from the primary heat exchanger. A collection/discharge box fluidly couples an outlet of the primary heat exchanger and an inlet of the secondary heat exchanger. An enclosure houses the primary heat exchanger, the collection/discharge box, and the secondary heat exchanger, and includes an air inlet and an air outlet. A main air flow path extends through the enclosure from the air inlet to the air outlet, and the primary and secondary heat exchangers are arranged along the main air flow path. An air bypass channel is arranged to be fluidly parallel to a section of the main air flow path, and the collection/discharge box is arranged along the bypass channel.

Abstract: An air inlet hood for use with a ventilation system has an air inlet face to receive a flow of fresh ventilation air, and an air outlet face to deliver the air into the ventilation system. A rainwater collection channel is disposed along edges bounding the air inlet face to collect rainwater falling on the air inlet hood. A rainwater reservoir receives the collected rainwater from the rainwater collection channel, and dispenses the collected rainwater away from the air inlet face in order to prevent rainwater from being entrained into the ventilation air.

Abstract: An air inlet hood for use with a ventilation system has an air inlet face to receive a flow of fresh ventilation air, and an air outlet face to deliver the air into the ventilation system. A rainwater collection channel is disposed along edges bounding the air inlet face to collect rainwater falling on the air inlet hood. A rainwater reservoir receives the collected rainwater from the rainwater collection channel, and dispenses the collected rainwater away from the air inlet face in order to prevent rainwater from being entrained into the ventilation air.

Abstract: A furnace for heating air includes a primary heat exchanger and a secondary heat exchanger to transfer heat from a flow of hot gases, the secondary heat exchanger being arranged downstream from the primary heat exchanger. A collection/discharge box fluidly couples an outlet of the primary heat exchanger and an inlet of the secondary heat exchanger. An enclosure houses the primary heat exchanger, the collection/discharge box, and the secondary heat exchanger, and includes an air inlet and an air outlet. A main air flow path extends through the enclosure from the air inlet to the air outlet, and the primary and secondary heat exchangers are arranged along the main air flow path. An air bypass channel is arranged to be fluidly parallel to a section of the main air flow path, and the collection/discharge box is arranged along the bypass channel.

Abstract: A gas-fired unit heater (10) is provided and includes a burner (20), a heat exchanger tube (18) located to receive a flow of the combustion products from the burner (20), the tube (18) including at least one linear tube run (30) extending along a longitudinal axis (18), and a corrugated baffle (40) received in the tube run (30).