Abstract: An HVAC system having an airflow path, a primary heat exchanger disposed along the airflow path, wherein the airflow path at least partially passes through the primary heat exchanger, and a multipurpose cabinet selectively configurable between at least a first configuration for housing a first type of auxiliary heat transfer component and a second configuration for housing a second type of auxiliary heat transfer component, wherein the airflow path at least partially passes through the multipurpose cabinet.

Abstract: An air handling unit has an interior wall configured to selectively retain a removable component of the air handling unit. An air handling unit has an interior wall configured as a drain pan. An air handling unit has an outer skin joined to the interior wall, an insulator disposed between the interior wall and the outer skin, and the interior wall has a mounting channel configured to selectively retain a removable component of the air handling unit.

Abstract: An air handling unit has a first modular cabinet comprising a first profile, a second modular cabinet comprising a second profile that is complementary to the first profile, and the first profile comprises an alignment feature. An air handling unit has a heat exchanger cabinet comprising a first profile, a blower cabinet comprising a second profile complementary to the first profile, a first connector system disposed at least partially on each of the heat exchanger cabinet and the blower cabinet, and the first connector system is operable to releasably secure the first profile to the second profile. An air handling unit has a first modular cabinet comprising a first portion of a first connection system and a second modular cabinet comprising a second portion of the first connection system. A component of the first portion may be least partially received within the second portion.

Abstract: Systems and methods for fault detection and diagnosis (FDD) in a heating, ventilation and air conditioning (HVAC) system include a server identifying a fault and one or more predicted causes of the fault based on measurements of operational parameters from the HVAC system. The server also receives and utilizes information associated with the reported fault from service technicians who service the HVAC to correct the reported fault condition. The information includes details of the corrective measures successfully implemented by the technicians to correct the fault, and a determination of whether the server correctly identified the actual fault. The information is implemented by the server to improve the accuracy of the FDD algorithms based on measured parameters of the HVAC system.

Abstract: A fault detection module and related methods of prognostic fault detection for an HVAC system are disclosed. Baseline operating parameters of an HVAC system operating in a known balanced state are collected during a calibration period. A set of coefficients for an enthalpy model are generated from the collected baseline parameters to define the balanced operation of the HVAC system. During normal operating times, runtime operating parameters of the HVAC system are collected. The expected high-side and low-side enthalpies are computed using the enthalpy model, and compared to actual high-side and low-side enthalpies. The relationships between expected and actual enthalpies are utilized to determine whether a potential or actual fault condition exists, and optionally, the nature of the fault. A fault message indicating the fault is transmitted to one or more recipient devices.

Abstract: A diagnostic data collection device and a diagnostic data bus are disclosed. In an embodiment, the diagnostic data collection device includes a diagnostic communication interface and a flexible interface module. The interface module is configurable to measure one or more electrical properties associated with an HVAC component, such as voltage, current, resistance. Electrical properties may include a sensor output and may include analog and digital signals. The diagnostic data collection device generates an exception message if the sensed property is out of specification. Evaluation rules are provided to detect various types of failures, including transient failures, steady state failures, and trending failures. The diagnostic data collection device self-calibrates by recording electrical properties during normal operation of the HVAC equipment.

Abstract: A method and system for detecting and diagnosing faults in a heating, ventilation and air conditioning (HVAC) system includes a remote server receiving data from sensors associated with the HVAC system. The data received includes measured sensor data, from both HVAC equipment and co-located sensors, and identifying criteria for identifying the piece of equipment associated with the sensor and/or identifying a location of the sensor, which may or may not be on or in the HVAC equipment. A probability that a fault exists and/or a likelihood of occurrence of a fault in one of the pieces of the equipment is calculated based on the data received, and an alert is generated in accordance with an analysis thereof, which may include comparison of the probability and/or likelihood with predetermined threshold(s).

Abstract: An air handling unit has a cabinet forming a duct, a mixed-flow blower assembly configured to provide airflow through the duct, and a refrigeration coil assembly disposed within the cabinet and downstream of the mixed-flow blower assembly. Another air handling unit has a cabinet forming a duct having a generally downstream direction and a blower assembly to provide airflow through the duct. The blower assembly may have an axis of rotation generally parallel to the downstream direction and the blower assembly may be configured to primarily expel air in a direction that has a directional component that extends radially away from the axis of rotation.

Abstract: A drain pan level monitoring system of an air conditioning system comprises a level sensor that generates a level sensor output signal related to a sensed level of condensation buildup within a drain pan. A method of monitoring a liquid level buildup in a drain pan of an air handling unit comprises determining a level of liquid buildup in the drain pan and determining whether an action should be taken in response to the determined level of liquid buildup by comparing the determined level of liquid buildup to a predetermined value. A method of preventing liquid overflow of a drain pan of an air handling unit comprises monitoring a pressure related to a liquid level buildup within the drain pan and taking an action when the pressure meets a predetermined criteria.

Abstract: An air handling unit has a blower assembly, a first interior zone, and a second interior zone and the blower assembly physically separates the first interior zone from the second interior zone. A method includes providing a cabinet configured to receive a blower assembly, inserting a blower assembly into the air duct, and closing a cabinet door of the cabinet, wherein upon closing the cabinet door, the primary air flow path from a location within the cabinet downstream of the blower assembly to a location within the cabinet upstream of the blower assembly is through a blower housing of the blower assembly. A blower assembly has a blower housing comprising at least one air inlet and at least one air outlet and a blower deck extending from the outlet, wherein the blower deck comprises at least one substantially flat component having a substantially orthogonal wall extending from the flat component.

Abstract: An HVAC system having an airflow path, a primary heat exchanger disposed along the airflow path, wherein the airflow path at least partially passes through the primary heat exchanger, and a multipurpose cabinet selectively configurable between at least a first configuration for housing a first type of auxiliary heat transfer component and a second configuration for housing a second type of auxiliary heat transfer component, wherein the airflow path at least partially passes through the multipurpose cabinet.

Abstract: An air handling unit has an interior wall configured to selectively retain a removable component of the air handling unit. An air handling unit has an interior wall configured as a drain pan. An air handling unit has an outer skin joined to the interior wall, an insulator disposed between the interior wall and the outer skin, and the interior wall has a mounting channel configured to selectively retain a removable component of the air handling unit.

Abstract: An air handling unit has a first modular cabinet comprising a first profile, a second modular cabinet comprising a second profile that is complementary to the first profile, and the first profile comprises an alignment feature. An air handling unit has a heat exchanger cabinet comprising a first profile, a blower cabinet comprising a second profile complementary to the first profile, a first connector system disposed at least partially on each of the heat exchanger cabinet and the blower cabinet, and the first connector system is operable to releasably secure the first profile to the second profile. An air handling unit has a first modular cabinet comprising a first portion of a first connection system and a second modular cabinet comprising a second portion of the first connection system. A component of the first portion may be least partially received within the second portion.

Abstract: An air handling unit has a cabinet forming a duct, a mixed-flow blower assembly configured to provide airflow through the duct, and a refrigeration coil assembly disposed within the cabinet and downstream of the mixed-flow blower assembly. Another air handling unit has a cabinet forming a duct having a generally downstream direction and a blower assembly to provide airflow through the duct. The blower assembly may have an axis of rotation generally parallel to the downstream direction and the blower assembly may be configured to primarily expel air in a direction that has a directional component that extends radially away from the axis of rotation.

Abstract: A drain pan level monitoring system of an air conditioning system comprises a level sensor that generates a level sensor output signal related to a sensed level of condensation buildup within a drain pan. A method of monitoring a liquid level buildup in a drain pan of an air handling unit comprises determining a level of liquid buildup in the drain pan and determining whether an action should be taken in response to the determined level of liquid buildup by comparing the determined level of liquid buildup to a predetermined value. A method of preventing liquid overflow of a drain pan of an air handling unit comprises monitoring a pressure related to a liquid level buildup within the drain pan and taking an action when the pressure meets a predetermined criteria.

Abstract: The present invention is a lightweight tent having a sloping roof that overhangs the door and preferably the base of the tent as well at one or both ends. This latter slope allows the tent to be erected using a single supporting member, and provides good ventilation while simultaneously providing good protection from the elements. The lightweight tent is constructed from a waterproof canopy having generally trapezoidal sides joined to a floor that preferably tapers from the front to the rear. Its roof slopes downward from the front to the rear, with at least its front side edges tilting toward the ridgeline at an angle less than ninety degrees.

Abstract: The present invention provides a method for establishing fixation during computerized visual field perimetry, requiring the subject to verbally identify the symbol employed as fixation targets as they each appear. Speech recognition techniques are then employed to evaluate the subject's response, and, upon correctly identifying the fixation symbol, a visual test stimulus is displayed at a predetermined location within the subject's field of vision. Fixation is established by displaying to the subject fixation targets represented by varying symbols, which may be displayed at one or more locations on a display monitor. These so-called fixation symbols, include geometrical shapes, letters, numbers, pictures or other symbols readily identifiable by the subject. When a fixation symbol appears, the subject verbally identifies the symbol by saying the name of the symbol into a microphone.

Abstract: An air conditioner includes an outdoor section comprising an outdoor coil, a fan, and a refrigerant compressor housed within a cabinet. The cabinet includes an outer wrapper supported by a plastic base. The base and wrapper include features that facilitate the cabinet's assembly and shipping, enhance its appearance, and ensure its functional and structural integrity. For example, the base includes breakaway shipping tabs, lead-ins that help guide the wrapper and coil into position during assembly, and snaps that help hold the wrapper in place with a minimal number of screws. The wrapper includes watertight screw-receiving dimples for mounting electrical hardware, side panels that interconnect by way of a novel vertically sliding fit, and a spacer for protecting the coil from being crushed by the wrapper. A frame that supports the fan also supports the cabinet's top cover.

Abstract: A novel contrast sensitivity test utilizing an adaptive contrast threshold algorithm is proposed. The contrast sensitivity test is embodied as a two-alternative forced choice examination using grating stimuli of randomly interleaved spatial frequencies. The stimulus's orientation is either tilted to the left or right of vertical. During an examination, a succession of grating stimuli is presented to the subject, and the subject asked to indicate the orientation of each stimulus. The contrast level for the next stimulus is varied depending on the subject's response to the previous one using an adaptive weighted up-down algorithm. For each correct response, the contrast level is reduced, whereas for each incorrect response the contrast level is increased. Importantly, the amount by which the contrast level is lowered is different from the amount by which it is raised, and as the examination progresses, the amount changes.

Abstract: A novel visual field test utilizing oscillating visual stimuli is proposed, which may be used to diagnose for eye disorders, such as glaucoma or macular degeneration. Such visual stimuli oscillate in color, polarity, saturation, luminance or intensity. Preferably, the visual test pattern consists of oscillating visual stimuli arranged in a pattern, such as a repeating or grid pattern, covering substantially all of the field of vision being tested. And, may include the use of frequency doubling visual stimuli. In use, the visual field test pattern is positioned in front of the patient so as to cover substantially all of the field of vision being tested, typically about a solid angle of 40° or more. The eye under examination is fixated, and the patient asked to indicate areas where the oscillating visual stimuli are dissimilar, such as by outlining those areas different from the rest of the visual field test pattern.