Wire detection for an HVAC controller

#The present disclosure pertains to a Heating, Ventilation, and/or Air Conditioning (HVAC) system for a building. More particularly, the present disclosure pertains to devices for controlling an HVAC system.

#Heating, Ventilation, and/or Air Conditioning (HVAC) systems are often used to control the comfort level within a building or other structure. Such HVAC systems typically include an HVAC controller that controls various HVAC components of the HVAC system in order to affect and/or control one or more environmental conditions within the building. In many cases, the HVAC controller is mounted within the building and provides control signals to various HVAC components of the HVAC system. Improvements in the hardware, user experience, and functionality of such HVAC controllers, including remote sensor devices, would be desirable.

#The disclosure is directed to HVAC controllers that are configured to receive signals such as temperature signals from a plurality of different temperature sensors, and to utilize these temperature signals in controlling an HVAC system. In a particular example of the disclosure, a Heating, Cooling and Ventilation (HVAC) controller for controlling an HVAC system within a building structure is configured to communicate with the HVAC system via field wires extending from the HVAC system to the HVAC controller. The HVAC controller includes a housing, a user interface accessible from an exterior of the housing, a temperature sensor disposed relative to the housing, a first input terminal configured to be electrically coupled with a first field wire, a second input terminal configured to be electrically coupled with a second field wire, and a double pole relay including two input terminals and two output terminals, wherein the two input terminals are operatively coupled to a power source, a first of the two output terminals is operatively coupled to the first input terminal, and a second of the two output terminals is operatively coupled to the second input terminal. The double pole relay includes an open state where the first and second of the two output terminals are disconnected from the two input terminals and thus the power source, and a closed state where the first and second of the two output terminals are connected to the power source via the two input terminals. Control circuitry is operably coupled to the temperature sensor and the double pole relay, wherein the control circuitry is configured change the double pole relay between the open state and the closed state based at least in part on a temperature sensed by the temperature sensor to control operation of at least part of the HVAC system. The control circuitry further includes a first wire sensing circuit operably coupled with the first input terminal, wherein when the double pole relay is the open state, the first wire sensing circuit is configured to electrically detect when the first field wire is electrically coupled with the first input terminal and a second wire sensing circuit operably coupled with the second input terminal, wherein when the double pole relay is the open state, the second wire sensing circuit is configured to electrically detect when the second field wire is electrically coupled with the second input terminal.

#The disclosure may be more completely understood in consideration of the following description of various illustrative embodiments of the disclosure in connection with the accompanying drawings, in which:

#FIG. 1 is a schematic view of an illustrative HVAC system servicing a building;

#FIG. 2 is a schematic view of an illustrative HVAC control system that may facilitate access and/or control of the HVAC system of FIG. 1;

#While the disclosure is amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit aspects of the disclosure to the particular illustrative embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the disclosure.

#The following description should be read with reference to the drawings wherein like reference numerals indicate like elements. The drawings, which are not necessarily to scale, are not intended to limit the scope of the disclosure. In some of the figures, elements not believed necessary to an understanding of relationships among illustrated components may have been omitted for clarity.

#All numbers are herein assumed to be modified by the term “about”, unless the content clearly dictates otherwise. The recitation of numerical ranges by endpoints includes all numbers subsumed within that range (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, and 5).