An indoor unit includes a housing that houses an electrical-component storage box that includes a body portion, a lid portion, and an engagement mechanism portion that engages the body portion and the lid portion with each other in a detachable manner. The lid portion covers an open region on a side of the body portion. The engagement mechanism portion includes an engagement claw portion provided at one of the body and lid portions and an engagement hole portion into which the claw portion is inserted, and which is formed at the other of the body and lid portions.

Air handling unit (1), AHU, comprises a plurality of modules (100), each of which includes a sensor (101), configured to detect values of a physical property and generate a control signal (101), an actuator (102), configured to perform air handling operations and a peripheral controller (103), connected to the sensor (101), to receive the control signal (101), and to the actuator (102), to control it through a command signal (102). The modules (100) of the plurality of modules are operatively interconnected according to a predetermined layout. The air handling unit (1), AHU includes a central control unit (200), connected to each peripheral controller (103), to exchange signals with each peripheral controller (103). Each peripheral controller (103) of the modules (100) of the plurality of modules is programmable, with the possibility of varying a control logic, in response to a location of the respective module (100) within the predetermined layout and/or depending on the sensor and the actuator connected to the correspondent peripheral controller.

Embodiments of the present disclosure provide a protection circuit and an air conditioner, which are applied to the field of air conditioner technologies and used to protect an indoor unit. The protection circuit provided by the embodiments of the present disclosure includes: a positive temperature coefficient thermistor; a signal input terminal; and a communication module; wherein a first end of the positive temperature coefficient thermistor is connected to the signal input terminal, and a second end of the positive temperature coefficient thermistor is connected to the communication module.

An air conditioning system has an air conditioner, which includes an outdoor unit and an indoor unit that configure a refrigerant circuit, and a controller, which controls the running of the air conditioner. The controller does not allow operation of the air conditioner to start in a case where a signal from a ventilation unit that includes a ventilation fan for ventilation and ventilates a target space or a refrigerant leak sensor that detects refrigerant leakage in the target space is not input to the controller. Because of this, even in a configuration where an air conditioner and a ventilation unit are installed independently of each other, operation of the air conditioner can be performed in a state in which there is reliably established a countermeasure such as the ventilation unit being operated when the refrigerant has leaked, and safety and security with respect to refrigerant leakage are reliably ensured.

A method for operating an air conditioner includes transmitting a plurality of signals between a remote user interface and the air conditioner through a plurality of wires that extend between the remote user interface and the air conditioner when the air conditioner is in a diagnostic mode. Each signal of the plurality of signals corresponds to a respective one of the plurality of wires. The method also include sequentially presenting a respective one or more characters on a display of a user interface of the air conditioner in response to each signal of the plurality of signals being received at the air conditioner.

Systems and methods are described for attributing a primary causative agent for HVAC system usage being above or below an average, the HVAC system being controlled by a self-programming network-connected thermostat. Systems and method are also described interactively and graphically displaying schedule information to a user of an HVAC system controlled by a network-connected thermostat. The displayed information can include indications of the manner in which one or more setpoints was created or last modified. Historical HVAC performance information can also be displayed that can include details of certain energy-effecting events such as setpoint changes, adaptive recovery, as well as automatic and manually set non-occupancy modes.

Apparatuses, systems, and methods for de-energizing an indoor HVAC unit are provided herein. The system comprises an outdoor HVAC unit, an indoor HVAC unit, signal cables coupled between the outdoor HVAC unit and the indoor HVAC unit, and an air-gap switch connected to the indoor HVAC unit. The signal cables are configured to electrically power the indoor HVAC unit from the outdoor HVAC unit. The air-gap switch is connected to the indoor HVAC unit and is configured to selectively sever a connection between the signal cables and the indoor HVAC unit. The air-gap switch provides an electrical safety measure for servicing and maintaining the indoor HVAC unit.

A thermostat that is configured to be releasably secured to a wall mountable connector, wherein the wall mountable connector includes a jumper switch that permits an installer or other professional to easily form an electrical connection between different wiring terminals of the wall mountable connector in accordance with how particular field wires are connected to the wiring terminals of the wall mountable connector. The thermostat is further configured to automatically determine the position of the jumper switch of the wall mountable connector, and in some cases, change the control of at least some functionality of the thermostat and/or HVAC equipment depending on the position of the jumper switch.

Systems and methods are described for attributing a primary causative agent for HVAC system usage being above or below an average, the HVAC system being controlled by a self-programming network-connected thermostat. Systems and method are also described interactively and graphically displaying schedule information to a user of an HVAC system controlled by a network-connected thermostat. The displayed information can include indications of the manner in which one or more setpoints was created or last modified. Historical HVAC performance information can also be displayed that can include details of certain energy-effecting events such as setpoint changes, adaptive recovery, as well as automatic and manually set non-occupancy modes.

In certain embodiments, a controller turns a heat pump system on in heating mode or cooling mode and determines a position for the heat pump system's reversing valve based on an O/B setting. The O/B setting indicates to configure the reversing valve in a first position that causes refrigerant to flow in a first direction when in heating mode and in a second position that causes the refrigerant to flow in a second, opposite direction when in cooling mode. The controller determines whether to maintain or reverse the O/B setting. If the heat pump system heats while in the heating mode or cools while in the cooling mode, the O/B setting is maintained. If the heat pump system cools while in the heating mode or heats while in the cooling mode, the O/B setting is reversed.