An air conditioner shut-off system includes an overflow conduit that is coupled, at one end, to the drainage system of an air handler unit of the air conditioner system. The opposite end of the overflow conduit is positioned over an overflow container, which is suspended by a harness at the lower end of the harness. The upper end of the harness being operably coupled to the shut off switch throw of a shut off switch, which is provided on or proximate to the air handler unit. If the drainage system becomes obstructed, water will flow into the overflow container through the conduit, and eventually the mass of the water accumulated in the overflow container will produce enough force acting on the shut off switch throw through the harness to flip the shut off switch throw to the OFF position, resulting in the air conditioner system being shut off.

In various examples, the subject matter of this disclosure relates to devices, systems, and methods for air purification systems. According to one embodiment, a multi-filtration air purification system can include a photocatalytic oxidizer (PCO) filter including an ultraviolet (UV) emitter, the PCO filter disposed within an air filter receiving region of the air purification system. In one implementation, the air purification system can include a removable air filter disposed over the PCO filter and located within the air filter receiving region, where the removable air filter can include a switch trigger. In some instances, the air filter receiving region can include a switch configured to receive the switch trigger, where the switch and switch trigger together are configured to disable operation of the air purification system when the removable air filter is removed from the air filter receiving region.

In various examples, the subject matter of this disclosure relates to devices, systems, and methods for air purification systems. According to one embodiment, a multi-filtration air purification system can include a photocatalytic oxidizer (PCO) filter including an ultraviolet (UV) emitter, the PCO filter disposed within an air filter receiving region of the air purification system. In one implementation, the air purification system can include a removable air filter disposed over the PCO filter and located within the air filter receiving region, where the removable air filter can include a switch trigger. In some instances, the air filter receiving region can include a switch configured to receive the switch trigger, where the switch and switch trigger together are configured to disable operation of the air purification system when the removable air filter is removed from the air filter receiving region.

A refrigeration cycle apparatus (1) is capable of performing a refrigeration cycle using a small-GWP refrigerant. The refrigeration cycle apparatus (1) includes a refrigerant circuit (10) and a refrigerant enclosed in the refrigerant circuit (10). The refrigerant circuit includes a compressor (21), a condenser (23), a decompressing section (24), and an evaporator (31). The refrigerant contains at least 1,2-difluoroethylene.

A refrigeration cycle apparatus (1) is capable of performing a refrigeration cycle using a small-GWP refrigerant. The refrigeration cycle apparatus (1) includes a refrigerant circuit (10) and a refrigerant enclosed in the refrigerant circuit (10). The refrigerant circuit includes a compressor (21), a condenser (23), a decompressing section (24), and an evaporator (31). The refrigerant contains at least 1,2-difluoroethylene.

A server rack includes an air inlet configured to intake air from outside of the server rack, an air exhaust outlet configured to exhaust air to an outside of the server rack, an inlet temperature sensor configured to measure the temperature of inlet air, a heat exchanger provided at an air exhaust outlet of the server rack, a power consumption sensor provided to a power supply of the server rack and configured to measure electrical power consumption of the server rack, and a heat exchange controller configured to control heat exchange between the heat exchanger and the exhaust air based on measurements from the inlet temperature sensor and the power consumption sensor.

A server rack includes an air inlet configured to intake air from outside of the server rack, an air exhaust outlet configured to exhaust air to an outside of the server rack, an inlet temperature sensor configured to measure the temperature of inlet air, a heat exchanger provided at an air exhaust outlet of the server rack, a power consumption sensor provided to a power supply of the server rack and configured to measure electrical power consumption of the server rack, and a heat exchange controller configured to control heat exchange between the heat exchanger and the exhaust air based on measurements from the inlet temperature sensor and the power consumption sensor.

An ECM including a motor body and a motor controller. The motor body includes a stator assembly. The stator assembly includes a stator winding. The motor controller includes a control circuit board, and the control circuit board includes a power source, a microprocessor, an insulated-gate bipolar transistor (IGBT) inverter circuit, and a plurality of universal interface modules. The motor controller is configured to be connected to a main control board of a heating, ventilation, and air conditioning (HVAC) system, to receive a command from the HVAC system, and to control the operation of the motor body based on the command. The power source is configured to supply power to each electric circuit of the motor controller. The IGBT inverter circuit includes an output terminal; the stator winding includes a coil winding; and the output terminal is connected to the coil winding.

An ECM including a motor body and a motor controller. The motor body includes a stator assembly. The stator assembly includes a stator winding. The motor controller includes a control circuit board, and the control circuit board includes a power source, a microprocessor, an insulated-gate bipolar transistor (IGBT) inverter circuit, and a plurality of universal interface modules. The motor controller is configured to be connected to a main control board of a heating, ventilation, and air conditioning (HVAC) system, to receive a command from the HVAC system, and to control the operation of the motor body based on the command. The power source is configured to supply power to each electric circuit of the motor controller. The IGBT inverter circuit includes an output terminal; the stator winding includes a coil winding; and the output terminal is connected to the coil winding.

A UV light disinfectant system is provided that addresses the problems associated with catastrophic failure of the device due to the presence of moisture or corrosive elements getting into the light fixture and damaging internal power connections of the device. Additionally, the UV light disinfectant system is provided with safety features that prevent unintentional exposure of maintenance personnel to the intense UV light used to disinfect air passing through the duct on which the device is mounted.