A hookah device having a heating unit, a head for holding a cooking element, a pipe, and a base. The heating unit for use with the hookah device can be provided with optimally placed vents along a bottom wall, a sidewall, and a top wall to facilitate circulation of fresh air and heated air. An optional thermometer can be mounted to the housing for recording a temperature reading with a combustion chamber of the heating unit.

A furnace includes a gas burner exposed to a heat-exchange tube. An inducer is fluidly coupled to the heat-exchange tube and configured to induce draft air through the heat-exchange tube. A regulator is fluidly coupled to the gas burner. A rollout shield is disposed adjacent to the gas burner. A rollout switch is disposed in the rollout shield. The rollout switch is electrically coupled to the regulator. At least one vent is formed through the rollout shield adjacent to the rollout switch. The vent provides a path for a rollout flame to the rollout switch. The at least one vent is disposed on at least two sides of the rollout switch.

An air handling unit (AHU) for a heating, ventilation, air conditioning, and refrigeration (HVACR) system includes a housing and a combustion heater disposed within the housing. The housing includes a combustion section with a first channel and a second channel. The combustion heater includes heat exchanger tubes and a tube support that supports heat exchanger tubes within the combustion section. The tube support slidably disposed in the first channel and the second channel. The combustion heater configured to be slidably removable from the AHU. An AHU for an HVACR system includes a housing with a fan section and a fan assembly disposed within the housing. The fan assembly including a pair of grooves slidably disposed on a pair of rails of the housing. The fan assembly configured to be both slidably removable from the AHU and liftably removable from the AHU.

An air handling unit (AHU) for a heating, ventilation, air conditioning, and refrigeration (HVACR) system includes a housing and a combustion heater disposed within the housing. The housing includes a combustion section with a first channel and a second channel. The combustion heater includes heat exchanger tubes and a tube support that supports heat exchanger tubes within the combustion section. The tube support slidably disposed in the first channel and the second channel. The combustion heater configured to be slidably removable from the AHU. An AHU for an HVACR system includes a housing with a fan section and a fan assembly disposed within the housing. The fan assembly including a pair of grooves slidably disposed on a pair of rails of the housing. The fan assembly configured to be both slidably removable from the AHU and liftably removable from the AHU.

A fault detection system for detecting a flow restriction in an air handler is provided. The system includes a coil, air and liquid temperature sensors, a smart valve and a notification device. The coil is located in an air stream of the air handler. The air temperature sensors are located in the air stream, one sensor determining an air temperature of air upstream of the coil and another determines an air temperature downstream of the coil. The liquid temperature sensors determine a liquid temperature entering the coil and exiting the coil. The smart valve includes a controller in communication with the liquid temperature sensors and at least one of the air temperature sensors that uses the measured air temperature downstream of the coil and a valve actuator position to determine whether the coil is operating at a reduced capacity. The notification device communicates with the controller of the smart valve.

A fault detection system for detecting a flow restriction in an air handler is provided. The system includes a coil, air and liquid temperature sensors, a smart valve and a notification device. The coil is located in an air stream of the air handler. The air temperature sensors are located in the air stream, one sensor determining an air temperature of air upstream of the coil and another determines an air temperature downstream of the coil. The liquid temperature sensors determine a liquid temperature entering the coil and exiting the coil. The smart valve includes a controller in communication with the liquid temperature sensors and at least one of the air temperature sensors that uses the measured air temperature downstream of the coil and a valve actuator position to determine whether the coil is operating at a reduced capacity. The notification device communicates with the controller of the smart valve.

Tubing structures are connected to each other to form a tubing assembly having one or more fluid pathways from a fluid entrance to a fluid exit. A heating device is bonded to the tubing structures along a length of the tubing assembly. The heating device has a flexibility to follow along one or more bends present along the length of the tubing assembly. The heating device includes one or more heater traces embedded within an encasing material. The encasing material is thermally conductive and electrically insulative. The one or more heater traces are formed of a material that generates heat in the presence of an electrical current. The heating device has a continuous and unbroken structure along the length of the tubing assembly. An encapsulation layer of thermal insulating material is disposed over the tubing assembly and covers the heating device.

A furnace for a heating, ventilation, and/or air conditioning (HVAC) system includes a first set of heat exchanger tubes positioned within an air flow path of the furnace through which an air flow may be directed, a second set of heat exchanger tubes positioned within the air flow path of the furnace, and a deflector baffle positioned within the air flow path and configured to direct a portion of the air flow toward the second set of heat exchanger tubes. The first set of heat exchanger tubes, the deflector baffle, and the second set of heat exchanger tubes are each respectively offset from one another in a direction of the air flow along the air flow path.

A burner assembly according to aspects of the disclosure includes a burner surface carried by a burner, the burner surface extending outward from a front side of the burner, a housing coupled to the burner on a side opposite the front side of the burner, a gasket disposed between the burner and the housing, a thermally anisotropic protective covering located on the front side of the burner and surrounding a perimeter of the burner surface, and an igniter positioned adjacent to the burner surface.

A high turndown furnace for an air handling system. In one example, the furnace includes a plurality of tubes divisible by four with a first modulating valve supplying gas to ¼ of the tubes and a second modulating valve supplying gas to ¾ of the tubes. In one aspect, the furnace is capable of providing a 16:1 turndown. In one aspect, the furnace is capable of providing seamless turndown operation throughout the entire firing range.