Abstract:
Systems and methods are disclosed for validating the installation and operation of a fault detection and diagnostic module that monitors a component of an HVAC system. A remote diagnostic server is in operative communication with the HVAC system, and with the fault detection and diagnostic module. A user device communicates data to the remote diagnostic server that defines an association between the fault detection and diagnostic module and the HVAC system. The remote diagnostic server initiates an installation validation by sending a command to the HVAC system that causes the monitored component to initiate an event that is expected to be reported by the fault detection and diagnostic module. For example, a fan motor is turned on. If correctly installed, the fault detection and diagnostic module senses the event, and reports the event to the remote diagnostic server, which confirms the association. The remote diagnostic server sends a message to the user device indicating the result of the validation.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of and priority to U.S. Provisional Application Ser. No. 62/328,791 entitled “METHOD OF ASSOCIATING A DIAGNOSTIC MODULE TO HVAC SYSTEM COMPONENTS” and filed Apr. 28, 2016, the entirety of which is hereby incorporated by reference herein for all purposes. 
     
    
     BACKGROUND 
     1. Technical Field 
       [0002]    The present disclosure is directed to fault detection and diagnostics in a heating, air conditioning, and ventilation (HVAC) system, and in particular, to systems and methods for verifying proper installation and operation of a fault detection and diagnostic module with respect to an associated HVAC component. 
       2. Background of Related Art 
       [0003]    HVAC systems include a number of components that are subject to wear and tear or other faults, which, if undetected, can degrade system efficiency, cause component failure or system shutdown, and, ultimately, cause customer dissatisfaction. As a result, manufacturers have placed increased emphasis on the detection and diagnosis of HVAC component faults in order to enhance the reliability of HVAC systems, and to reduce the impact of faults when they do occur. 
         [0004]    A typical HVAC system includes components such as a compressor, an outdoor unit fan, and an indoor unit fan, each of which is driven by its own electric motor. Some HVAC systems include other components, such as auxiliary heaters, reversing valves (e.g., as employed in a heat pump), dampers, and so forth. If a failure occurs in an HVAC component, a service technician is called to the site to troubleshoot the problem using diagnostic tools such as multimeters, pressure and temperature gauges, and so forth. Some HVAC systems include a self-diagnosis feature which displays diagnostic information, such as a trouble code, on a display panel accessible to a technician at the site. Such self-diagnostic features may have limited benefit, because the information provided by such a feature is only available at the unit (which may be in a hard-to-reach location, such as an attic or crawl space), and may not include information about other components in the system. 
         [0005]    Dedicated monitoring devices have been devised which collect diagnostic data from HVAC components during operation, however many service technicians have been reluctant to embrace this technology because installing and configuring these devices can be tedious, error-prone, and time-consuming. An HVAC monitoring device which is easily installable and configurable would be a welcome advance in the art. 
       SUMMARY 
       [0006]    In one aspect, the present disclosure is directed to a method for a diagnostic server to digitally associate a diagnostic module with a system controller, such as a thermostat, in an HVAC system. In an exemplary embodiment, the method includes the server sending a command message to the thermostat directing operation of a component in the HVAC system. The diagnostic module detects a process response in the HVAC system and sends a message to the server reporting the process response. The message may include HVAC system identifying information. The server associates the thermostat with the diagnostic module based on the process response message. 
         [0007]    In some embodiments, the method includes establishing a connection between the server and the diagnostic module through a router. In some embodiments, the identifying information includes an Internet address for the router. In some embodiments, the command message is sent to the thermostat through the router. In some embodiments, the method includes a user initiating the associating process on the thermostat. In some embodiments, the diagnostic module automatically requests initiation of the associating process after the connection is established. In some embodiments, a user establishes the connection by interacting with the diagnostic module through a user interface and further comprising the user initiating the associating process by establishing the connection. 
         [0008]    In another aspect, the present embodiment is directed to a diagnostic server for an HVAC system. The HVAC system includes a thermostat having an Internet connection through a router, indoor HVAC equipment in communication with the thermostat and outdoor HVAC equipment in communication with the thermostat. The indoor and/or outdoor HVAC equipment may be coupled to the thermostat via a wired (e.g., electrical or optical) or wireless (e.g., WiFi, Z-Wave, Zigbee, Bluetooth) connection. The HVAC system includes one or more diagnostic modules that receive sensor data from the indoor HVAC equipment and the outdoor HVAC equipment, and send messages through the Internet to a diagnostic server. At least one of the diagnostic modules has a wireless Internet connection through a router to the diagnostic server. The diagnostic server includes an Internet interface configured to send a command message to the thermostat directing operation of one or more components in the indoor HVAC equipment and the outdoor HVAC equipment, and receive a message comprising HVAC system identifying information and HVAC system process information from the diagnostic module. The diagnostic server also includes a database configured to record the association of the thermostat with the diagnostic module. 
         [0009]    In some embodiments, the HVAC system identifying information includes an Internet address for the router. In some embodiments, the diagnostic server is configured to receive an initiating message from the thermostat. In some embodiments, the diagnostic server is configured to receive an initiating message from the diagnostic module. In some embodiments, the diagnostic server is configured to send a message though the diagnostic module to a user interface indicating the association of the thermostat with the diagnostic module. 
         [0010]    In yet another aspect, the present disclosure is directed to a fault detection and diagnostic module for use with an HVAC component. In an exemplary embodiment, the fault detection and diagnostic module includes an electrical interface configured for receiving a sensed property of the HVAC component, a wireless network interface configured for operation in an ad-hoc mode and an infrastructure mode, a processor, and non-transitory memory. The non-transitory memory includes a set of executable instructions which, when executed by the processor, cause the fault detection and diagnostic module to operate the wireless network interface in an ad-hoc mode to communicate with a user device, receive network credentials from the user device, utilize the network credentials operate the wireless network interface in an infrastructure mode to communicate with a wireless router, and transmit an association request via the wireless network interface in an infrastructure mode to a remote diagnostic server. 
         [0011]    In some embodiments, the set of executable instructions cause the fault detection and diagnostic module to receive an association results message from the remote diagnostic server indicative of the results of an association process. In some embodiments, the executable instructions cause the fault detection and diagnostic module to transmit a message based at least in part upon the association results message to the user device. In some embodiments, the set of executable instructions cause the fault detection and diagnostic module to receive an association initialization request from the user device. In some embodiments, the set of executable instructions cause the fault detection and diagnostic module to transmit a diagnostic message to the remote diagnostic server in accordance with a sensed property of the HVAC component received by the electrical interface. 
         [0012]    In some embodiments, the fault detection and diagnostic module includes a diagnostic data bus communications interface configured for receiving diagnostic data from a second fault detection and diagnostic module. In some embodiments, the set of executable instructions cause the fault detection and diagnostic module to transmit diagnostic data received from a second fault detection and diagnostic module to the remote diagnostic server. 
         [0013]    In still another aspect, the present disclosure is directed to an HVAC diagnostic system. In an exemplary embodiment, the HVAC diagnostic system includes an HVAC system which includes a thermostat having an Internet connection through a router, indoor HVAC equipment comprising a plurality of components electrically connected to the thermostat, outdoor HVAC equipment comprising a plurality of components electrically connected to the thermostat, and one or more diagnostic modules having a wireless Internet connection through a router, wherein the diagnostic modules receive sensor data from the indoor HVAC equipment and the outdoor HVAC equipment and send messages through the Internet. The HVAC diagnostic system also includes a diagnostic server having an Internet interface configured to send a command message to the thermostat directing operation of the plurality of components in the indoor HVAC equipment and the outdoor HVAC equipment and receive a message comprising HVAC system identifying information and HVAC system process information from the one or more diagnostic modules, and a database configured to record an association of the thermostat with the diagnostic module. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]    Various embodiments of the disclosed system and method are described herein with reference to the drawings wherein: 
           [0015]      FIG. 1  is a block diagram of an HVAC diagnostic system configured for automatic association of a diagnostic module with a diagnostic server in accordance with an embodiment of the present disclosure; 
           [0016]      FIG. 2  is a pictorial diagram of the HVAC diagnostic system of  FIG. 1  installed at a customer site; 
           [0017]      FIG. 3A  illustrates a user interface for associating an HVAC diagnostics module in accordance with an embodiment of the present disclosure; 
           [0018]      FIG. 3B  illustrates another user interface for associating an HVAC diagnostics module in accordance with an embodiment of the present disclosure; 
           [0019]      FIG. 3C  illustrates yet another user interface for associating an HVAC diagnostics module in accordance with an embodiment of the present disclosure; and 
           [0020]      FIG. 4  is a flow chart illustrating a method of associating a diagnostic module with a thermostat in an HVAC system in accordance with an embodiment of the present disclosure. 
       
    
    
       [0021]    The various aspects of the present disclosure mentioned above are described in further detail with reference to the aforementioned figures and the following detailed description of exemplary embodiments. 
       DETAILED DESCRIPTION 
       [0022]    Particular illustrative embodiments of the present disclosure are described hereinbelow with reference to the accompanying drawings; however, the disclosed embodiments are merely examples of the disclosure, which may be embodied in various forms. Well-known functions or constructions and repetitive matter are not described in detail to avoid obscuring the present disclosure in unnecessary or redundant detail. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present disclosure in virtually any appropriately detailed structure. In this description, as well as in the drawings, like-referenced numbers represent elements which may perform the same, similar, or equivalent functions. The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments. The word “example” may be used interchangeably with the term “exemplary.” 
         [0023]    The present disclosure is described herein in terms of functional block components and various processing and communication steps. It should be appreciated that such functional blocks configured to perform the specified functions may be embodied in analog circuitry, digital circuitry, and/or instructions executable on a processor. For example, the present disclosure may employ various discrete components, integrated circuit components (e.g., memory elements, processing elements, communications elements, logic elements, look-up tables, and the like) which may carry out a variety of functions, whether independently, in cooperation with one or more other components, and/or under the control of one or more processors or other control devices. It should be appreciated that the particular implementations described herein are illustrative of the disclosure and its best mode and are not intended to otherwise limit the scope of the present disclosure in any way. 
         [0024]    The present disclosure is directed to improved systems and methods for associating an internet-enabled HVAC diagnostic module with the specific HVAC equipment to which the diagnostic module is connected. The disclosed method provides a closed-loop confirmation that eliminates the need for manual or human intervention, thus saving time and eliminating data entry errors. A command or set of commands is initiated by a remote diagnostic server and sent to a thermostat, which, in turn, controls the monitored equipment. The equipment&#39;s response to this command is then sensed by the diagnostic module, and transmitted back to the diagnostic server. Upon receiving this data, the diagnostic server is able to confirm that proper association between the diagnostic module and equipment has been established. The diagnostic server stores the identity of the thermostat and of the diagnostic modules as being associated at a single customer site, such as a residence or commercial building. This information may also stored in association with a customer account for providing service, for collecting performance and fault data for analysis, and so forth. 
         [0025]    An HVAC installation includes a diagnostic module configured to monitor the indoor HVAC unit and the outdoor HVAC unit. The diagnostic module includes a wireless interface (e.g., a WiFi interface) to provide connectivity to the remote diagnostic server. In some embodiments, an indoor diagnostic module is configured to monitor the indoor HVAC unit, and an outdoor diagnostic module is configured to monitor the outdoor HVAC unit. Indoor and outdoor diagnostic modules communicate with each other via a dedicated diagnostic bus. The outdoor diagnostic module communicates its diagnostic information to the indoor module. The indoor module communicates its diagnostic information, as well as diagnostic information received from the outdoor module, to the remote diagnostic server. A diagnostic server, diagnostic modules, and a dedicated diagnostic data bus for use with an HVAC system are disclosed in co-owned U.S. Utility patent application Ser. No. 15/006,651, filed Jan. 26, 2016, entitled “Remote Monitoring of an HVAC System for Fault Detection and Diagnostics” and in co-owned U.S. Utility patent application Ser. No. 15/006,584, filed Jan. 26, 2016, entitled “Diagnostic Data Bus for Acquiring and Communicating Diagnostic Information from HVAC Systems,” the entirety of each which is incorporated herein by reference. 
         [0026]    Initially, the indoor diagnostic module is configured to become a member of a wireless WiFi network at the site. To accomplish this, upon initial power-up, or alternatively, in response to a user input such as a button-press, the diagnostic module provides an ad-hoc WiFi network to which a user device (smart phone, tablet, notebook computer, etc.) is joined. The indoor diagnostic module includes a webserver which provides a web-based interface to the user device upon establishment of the ad-hoc connection, which facilitates entry of local WiFi authentication credentials (SSID, and if required, a wireless password) for the wireless router at a particular site into indoor diagnostic module the indoor diagnostic module. The indoor diagnostic module then uses the authentication credentials to connect to the local WiFi network to establish an Internet connection through the wireless router. 
         [0027]    To associate the diagnostic module to the HVAC system, the diagnostic module passes a request, which contains the public IP of the local site (or an alternate unique identifier) to the diagnostic server. When the diagnostic server receives this request, it in turn issues a command to the thermostat associated with the same public IP (or same alternate unique identifier) as the diagnostic module. For example, a command “turn on the indoor blower” is sent to the thermostat, which in turn, causes the indoor blower to turn on. By design, the diagnostic module senses the fact that the indoor blower has been activated, and communicates data conveying this fact back to the diagnostic server. Once the diagnostic server receives the expected response from the diagnostic module, e.g., that the indoor blower is indeed on, the association between the diagnostic module(s) and the premises HVAC equipment is confirmed. A unique identifier of the diagnostic module is stored by the diagnostic server, together with a unique identifier of the thermostat, and other information relating to the installation (e.g., account identification, customer name, address, equipment model numbers, installation date, warranty information, customer service notes, historical fault and service data, and so forth). 
         [0028]    With reference to  FIG. 1 , an exemplary embodiment of an HVAC diagnostic system  10  configured for automatic association of a diagnostic module  28 ,  30  with a diagnostic server  16  is shown. The system  10  includes a diagnostic server  16  that is specially configured to implement and execute the methods of the present disclosure and for operative communication with one or more components of an HVAC system  11 . HVAC system includes a thermostat  14  in operative communication with an HVAC indoor unit  24  and an HVAC outdoor unit  26 . Indoor unit  24  includes an electrically-powered blower to circulate indoor air through indoor unit  24 , and may be configured as a furnace/evaporator coil combination unit, a package unit, a modular air handler, a dedicated air handler, and the like. Outdoor unit  26  includes an electrically-powered compressor and an electrically-powered fan, and may be configured as an air conditioner condensing unit or a heat pump. 
         [0029]    Thermostat  14  controls the operation of indoor unit  24  and outdoor unit  26  via local control bus  20 . Local control bus  20  operates using any communications protocol suitable for use in HVAC system  11 . For example, and without limitation, where indoor unit  24  and/or outdoor unit  26  employ single- or dual-speed motors, local control bus  20  may operate using 24V switched circuits which typically correspond to well-known color coding schemes (Rc, Rh, C, Y, W, Y2, W2, G, E, O, V, etc.). In variable-speed installations, local control bus  20  may employ digital signaling protocols such as, without limitation, CAN bus, RS-485, ComfortLink II™, ClimateTalk™, and the like. 
         [0030]    Thermostat  14  controls the operation of indoor unit  24  and/or outdoor unit  26  in accordance with user inputs (eg., temperature setpoints, scheduled setbacks, and the like) in combination with environmental inputs (such as those obtained from, e.g., temperature, humidity, and/or occupancy sensors) to achieve the desired environmental conditions within the premises  13  in which HVAC system  11  is installed. Thermostat  14  additionally is configured to control the operation of indoor unit  24  and/or outdoor unit  26  in accordance with remote commands received from diagnostic server  16 , enabling indoor unit  24  and/or outdoor unit  26  to be remote-controlled by diagnostic server  16 . 
         [0031]    Thermostat  14  includes a unique identifier  15 , such as an electronic serial number, an IP address, and/or combinations thereof, which identifies thermostat  14  to diagnostic server  16 . Indoor diagnostic module  28  includes a unique identifier  29 , such as an electronic serial number, an IP address, and/or combinations thereof, which identifies indoor diagnostic module  28  to diagnostic server  16 . At least a portion of the unique identifier  15  and/or unique identifier  29  may be stored in read-only (unalterable) memory included within thermostat  14  and/or indoor diagnostic module  28 , respectively. It is an aspect of the present disclosure to enable the diagnostic server  16  to associate the unique identifier  15  of thermostat  14  with the unique identifier  29  of indoor diagnostic module  28  in a substantially automated manner, e.g., with minimal or no human intervention. 
         [0032]    In some embodiments, where the HVAC system does not include a traditional thermostat in favor of a separate HVAC system controller or an HVAC system controller included with another HVAC component (e.g., an air handler or furnace), the techniques described herein may be used to associate a diagnostic module with the HVAC system controller in use with any particular system. 
         [0033]    Indoor diagnostic module  28  is configured to sense one or more operational parameters of indoor unit  24  and communicate data indicative of the sensed parameters to diagnostic server  16 . Examples of operational parameters of indoor unit  24  which may be sensed by indoor diagnostic module  28  include, without limitation, blower motor current, blower motor speed, indoor liquid temperature, air inlet temperature, air outlet temperature, and so forth. Outdoor diagnostic module  30  is configured to sense one or more operational parameters of outdoor unit  26  and communicate data indicative of the sensed parameters to indoor diagnostic module  28 . Examples of operational parameters of outdoor unit  26  which may be sensed by outdoor diagnostic module  30  include, without limitation, compressor motor current, compressor motor speed, saturated suction pressure and/or temperature, saturated discharge pressure and/or temperature, fan motor current, fan motor speed, reversing valve status, and so forth. Indoor diagnostic module  28  is further configured to receive diagnostic data from outdoor diagnostic module  30  and to communicate the outdoor data to diagnostic server  16 . 
         [0034]    Indoor diagnostic module  28  includes a WiFi interface  27 . Upon initial power-up, or alternatively, in response to a user input such as a button-press, indoor diagnostic module  28  configures WiFi interface  27  to operate in an ad-hoc WiFi mode to enable a user device  32  to connect to indoor diagnostic module  28  to facilitate preliminary network setup, e.g., to establish a network connection between indoor diagnostic module  28  and router  12 . 
         [0035]    With reference now to  FIGS. 3A-3C , indoor diagnostic module  28  includes a webserver which provides a web-based interface  34  to the user device  32  upon establishment of the ad-hoc connection. User interface  34  includes a network SSID data entry field  35  and a password data entry field  36  into which a user enters the WiFi authentication credentials required to join the local WiFi network of router  12 . User interface  34  may include additional fields as required, for example, to enter an alternate unique identifier. Upon successful connection of indoor diagnostic module  28  to router  12 , an auto-associate button  37  enables the user to initiate an association process ( FIG. 3B ). In some embodiments, indoor diagnostic module  28  optionally or alternatively initiates the association process immediately upon successful connection to router  12 , e.g., without requiring the use of auto-associate button  37 . In yet other embodiments, a user may initiate the association process by employing an auto-associate button, or similar user interface element, that is provided by thermostat  14 . A status message  39  is displayed upon completion of the auto-association process ( FIG. 3C ). In some embodiments, a progress bar may be displayed to inform the user as steps of the process are completed. For example, “connecting to router,” “router connected,” “connecting to remote server,” “performing auto-association,” “association successful” and/or “association failure” may be presented on user interface  34  to keep the user informed as to the status of the HVAC diagnostic module association process. 
         [0036]    With reference to  FIG. 4 , an HVAC diagnostic module association process  100  in accordance with the present disclosure is described in more detail. In step  105 , a communications link is established between indoor diagnostic module  28  and remote diagnostic server  16 . In embodiments, the communications link is established, at least in part, by indoor diagnostic module  28  receiving authentication credentials required to join a wireless (WiFi) network which includes as one of its nodes thermostat  14 . In some embodiments, the communications link is established, at least in part, by indoor diagnostic module  28  obtaining a local network address (e.g., private IP address), which may be obtained via user input or may be obtained automatically from the network (e.g., via dynamic host configuration protocol, also referred to as DHCP). In some embodiments, internet connectivity between indoor diagnostic module  28  and remote diagnostic server  16  may be confirmed by sending a test message from indoor diagnostic module  28  to a remote network node (e.g., to remote diagnostic server  16 ) and receiving, at indoor diagnostic module  28 , a response therefrom to confirm the establishment of the network communication link. 
         [0037]    In step  110 , indoor diagnostic module  28  causes an association request message to be transmitted the remote diagnostic server. The association request message includes a unique identifier of the diagnostic module and the public IP address of indoor diagnostic module  28 . Note that, while indoor diagnostic module  28  and thermostat  14  each have distinct local (non-public) IP addresses, indoor diagnostic module  28  and thermostat  14  share a common public IP address identified with router  12 , which serves as the internet gateway for the local WiFi network for indoor diagnostic module  28  and thermostat  14 . 
         [0038]    Upon receipt of the association request, diagnostic server  16  queries a database to identify a thermostat having the same public IP as indoor diagnostic module  28 , which, here, is thermostat  14 . If additional information is required to facilitate remote communication between diagnostic server  16  and thermostat  14  (e.g., login credentials needed to remotely access thermostat  14 ), this information is retrieved from the database. In step  120 , the diagnostic server  16  transmits a remote command to thermostat  14  to change a current operational status of HVAC indoor unit  24  and/or HVAC outdoor unit  26 . An example remote command may include “turn on HVAC indoor unit  24 ,” “change compressor speed of HVAC outdoor unit  26 ” and so forth. 
         [0039]    In some embodiments, diagnostic server  16  will, upon receipt of an association request from diagnostic module  28 , transmit a remote command to thermostat  14  using the public IP address included within the association request, and, optionally, predetermined authentication credentials which are reserved for diagnostic use. In these embodiments, diagnostic server  16  is able to associate a diagnostic module  28  to HVAC system  11 , which includes thermostat  14 , HVAC indoor unit  24  and/or HVAC outdoor unit  26 , without the need for a customer account, or any other data relating to HVAC system, to be established or stored prior to performing association process  100 . 
         [0040]    Thermostat  14  executes the remote command received from diagnostic server  16 , which in turn, causes the specified HVAC component to perform the specified operation. If the diagnostic module connected to the specified HVAC component is properly installed and provisioned, it will sense the new operational state of the specified HVAC component, and, as expected, transmit a diagnostic message to remote server  16  that indicates the new operational state. If the expected message is received by diagnostic server  16 , the association is deemed a success, and the fact of the association is recorded by diagnostic server  16 . 
         [0041]    For example, if diagnostic server  16  sent a remote command “set compressor speed of outdoor unit to maximum” to thermostat  14 , HVAC outdoor unit  26  would respond in kind. Outdoor diagnostic module  30  then, if properly functioning, detects the compressor speed change exhibited by HVAC outdoor unit  26  and communicates a diagnostic message conveying the changed status to indoor diagnostic module  28  via dedicated diagnostic bus  22  (step  125 ). Next, indoor diagnostic module  28  transmits the diagnostic message to diagnostic server  16 . Note that the detection may be accomplished by, for example, a speed sensor (tachometer) coupled to the compressor shaft, by detecting an input current or other electrical property (e.g., back EMF) of the compressor motor, or by detecting a pressure or temperature differential seen between the compressor suction and discharge ports. 
         [0042]    In step  130 , if diagnostic server  16  receives the expected diagnostic message from the target diagnostic module, it is concluded in step  135  that the target diagnostic module is properly associated with thermostat  14 , HVAC system  11 , and/or premises  13  and, optionally, in the step  140  the fact of this association is recorded by diagnostic server  16  to facilitate subsequent diagnostic data analysis. On the other hand, if the expected diagnostic message is not received, in step  145  it is concluded that the association has failed. In some embodiments, if the diagnostic message is received but contains unexpected results, the association may be deemed inconclusive. In embodiments, diagnostic server  16  transmits a message indicating the results of the association process to indoor diagnostic module  28 . In embodiments, the results of the association process (success, failure, inconclusive) are conveyed by indoor diagnostic module  28  to user device  32  and/or thermostat  14 . In embodiments, the results of the association process are conveyed by diagnostic server  16  to indoor diagnostic module  28 , user device  32 , and/or thermostat  14 . 
         [0043]    In another aspect, an alternative method of association is disclosed which requires little or no user input. Since all thermostat events and all diagnostic events are stored in diagnostic server  16 , an attempt is made to automatically pair the devices by comparing the two sequences of events to identify a correlation between thermostat events (e.g., call for cooling) and diagnostic events (e.g., compressor on and indoor unit blower on) over a period of time. As the period of time that a correlation is identified increases, the confidence that the devices are connected to the same system also increases. After reaching a predetermined confidence threshold, the association of thermostat  14  and indoor diagnostic module  28  is deemed to be established. In embodiments, the results of the association process are conveyed by diagnostic server  16  to indoor diagnostic module  28 , user device  32 , and/or thermostat  14 . 
         [0044]    Note that, in order to efficiently match diagnostic devices and thermostats, only those devices and thermostats which are not known to be associated are considered for event sequence correlation. In some embodiments, an installer can initiate pairing by exercising some predetermined thermostat control gesture (e.g., fan mode: on-auto-on-auto a number of times). The predefined sequence of events emanating from each device (thermostat and diagnostic device) are detected by diagnostic server  16 , which, in turn, initiate correlation detection between thermostat events and diagnostic events. Such an approach also has advantages in that the installer is not required to generate any inputs into the thermostat other than to simply perform the predetermined thermostat control gesture. 
       ASPECTS 
       [0045]    It is noted that any of aspects 1-7, any of aspects 8-12, any of aspects 13-19, and/or aspect 20 may be combined with each other in any combination. 
         [0046]    Aspect 1. A method of a diagnostic server digitally associating a diagnostic module with a thermostat in an HVAC system, the method comprising the server sending a command message to the thermostat directing operation of a component in the HVAC system; the diagnostic module detecting a process response in the HVAC system and sending a message to the server reporting the process response and comprising HVAC system identifying information; and the server associating the thermostat with the diagnostic module. 
         [0047]    Aspect 2. The method according to aspect 1, further comprising establishing a connection between the server and the diagnostic module through a router. 
         [0048]    Aspect 3. The method according to any of aspects 1-2, wherein the identifying information includes an Internet address for the router. 
         [0049]    Aspect 4. The method according to any of aspects 1-3, wherein the command message is sent to the thermostat through the router. 
         [0050]    Aspect 5. The method according to any of aspects 1-4, further comprising a user initiating the associating process on the thermostat. 
         [0051]    Aspect 6. The method according to any of aspects 1-5, further comprising the diagnostic module automatically requesting initiation of the associating process after the connection is established. 
         [0052]    Aspect 7. The method according to any of aspects 1-6, wherein a user establishes the connection by interacting with the diagnostic module through a user interface and further comprising the user initiating the associating process by establishing the connection. 
         [0053]    Aspect 8. A diagnostic server for an HVAC system comprising a thermostat having an Internet connection through a router, indoor HVAC equipment electrically connected to the thermostat, outdoor HVAC equipment electrically connected to the thermostat, and one or more diagnostic modules having a wireless Internet connection through a router to the diagnostic server that receive sensor data from the indoor HVAC equipment and the outdoor HVAC equipment and send messages through the Internet to a diagnostic server, the server comprising an Internet interface configured to send a command message to the thermostat directing operation of one or more components in the indoor HVAC equipment and the outdoor HVAC equipment and receive a message comprising HVAC system identifying information and HVAC system process information from the diagnostic module; and a database configured to record the association of the thermostat with the diagnostic module. 
         [0054]    Aspect 9. The diagnostic server according to aspect 8, wherein the identifying information includes an Internet address for the router. 
         [0055]    Aspect 10. The diagnostic server according to any of aspects 8-9, further configured to receive an initiating message from the thermostat. 
         [0056]    Aspect 11. The diagnostic server according to any of aspects 8-10, further configured to receive an initiating message from the diagnostic module. 
         [0057]    Aspect 12. The diagnostic server according any of aspects 8-11, further configured to send a message though the diagnostic module to a user interface indicating the association of the thermostat with the diagnostic module. 
         [0058]    Aspect 13. A fault detection and diagnostic module for use with an HVAC component, comprising an electrical interface configured for receiving a sensed property of the HVAC component; a wireless network interface configured for operation in an ad-hoc mode and an infrastructure mode; a processor; and non transitory memory including a set of executable instructions which, when executed by the processor, cause the fault detection and diagnostic module to operate the wireless network interface in an ad-hoc mode to communicate with a user device; receive network credentials from the user device; utilize the network credentials operate the wireless network interface in an infrastructure mode to communicate with a wireless router; and transmit an association request via the wireless network interface in an infrastructure mode to a remote diagnostic server. 
         [0059]    Aspect 14. The fault detection and diagnostic module according to aspect 13, wherein the set of executable instructions, when executed by the processor, further cause the fault detection and diagnostic module to receive an association results message from the remote diagnostic server indicative of the results of an association process. 
         [0060]    Aspect 15. The fault detection and diagnostic module according to any of aspects 13-14, wherein the set of executable instructions, when executed by the processor, further cause the fault detection and diagnostic module to transmit a message based at least in part upon the association results message to the user device. 
         [0061]    Aspect 16. The fault detection and diagnostic module according to any of aspects 13-15, wherein the set of executable instructions, when executed by the processor, further cause the fault detection and diagnostic module to receive an association initialization request from the user device. 
         [0062]    Aspect 17. The fault detection and diagnostic module according to any of aspects 13-16, wherein the set of executable instructions, when executed by the processor, further cause the fault detection and diagnostic module to transmit a diagnostic message to the remote diagnostic server in accordance with a sensed property of the HVAC component received by the electrical interface. 
         [0063]    Aspect 18. The fault detection and diagnostic module according to any of aspects 13-17, further comprising a diagnostic data bus communications interface configured for receiving diagnostic data from a second fault detection and diagnostic module. 
         [0064]    Aspect 19. The fault detection and diagnostic module according to any of aspects 13-18, wherein the set of executable instructions, when executed by the processor, further cause the fault detection and diagnostic module to transmit diagnostic data received from a second fault detection and diagnostic module to the remote diagnostic server. 
         [0065]    Aspect 20. An HVAC diagnostic system, comprising an HVAC system comprising a thermostat having an Internet connection through a router; indoor HVAC equipment comprising a plurality of components electrically connected to the thermostat, outdoor HVAC equipment comprising a plurality of components electrically connected to the thermostat, and one or more diagnostic modules having a wireless Internet connection through a router, wherein the diagnostic modules receive sensor data from the indoor HVAC equipment and the outdoor HVAC equipment and send messages through the Internet; and a diagnostic server, comprising an Internet interface configured to send a command message to the thermostat directing operation of the plurality of components in the indoor HVAC equipment and the outdoor HVAC equipment, and receive a message comprising HVAC system identifying information and HVAC system process information from the one or more diagnostic modules; and a database configured to record an association of the thermostat with the diagnostic module. 
         [0066]    Particular embodiments of the present disclosure have been described herein, however, it is to be understood that the disclosed embodiments are merely examples of the disclosure, which may be embodied in various forms. Well-known functions or constructions are not described in detail to avoid obscuring the present disclosure in unnecessary detail. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present disclosure in any appropriately detailed structure.