Abstract: A method and a thermostat for a multi-thermostat temperature control system are provided. The system includes a thermostat including at least one processor communicatively coupled to at least one memory device. The thermostat is configured to receive one or more input signal commands permitting a recovery from a demand management system load shedding event and determine a pseudo-random starting time window from which a recovery starting time is selected. The pseudo-random starting time is based on a value accessible to the thermostat that is unique to the thermostat. The starting time window includes a primary delay window and a secondary delay window within the primary delay window. The thermostat is also configured to start an operation of a conditioning unit associated with the thermostat at the selected time.

Abstract: A system and a method of detecting a condensate line blockage in an air conditioning unit includes receiving a call for cooling indication from a thermostat associated with the air conditioning unit and detecting a pattern of a plurality of loss of power (LOP) to the air conditioning unit events, the LOP events caused by a trip of a condensate drain line switch. The method also includes analyzing the detected pattern for at least one of a frequency of LOP events in a predetermined time period and an elapsed time between successive LOP events, and initiating a condensate line blockage alert when the analyzed pattern meets predetermined condensate line blockage criteria.

Abstract: A multi-thermostat temperature control system and related methods include thermostats spaced about respective conditioning zones in conditioned spaces. The control system includes a thermostat controller configured to store a temperature setpoint value for each of the thermostats in an operating schedule. The thermostat controller is also configured to transmit a first control signal to the conditioning units to control an operation of the conditioning units to maintain a temperature of the conditioned spaces at a first respective temperature setpoint value and to receive offset values for respective ones of the thermostats wherein the one or more offset values are determined to counter the temperature effects of a local heat load in the conditioned spaces proximate an associated thermostat.

Abstract: A system and a method of detecting a condensate line blockage in an air conditioning unit includes receiving a call for cooling indication from a thermostat associated with the air conditioning unit and detecting a pattern of a plurality of loss of power (LOP) to the air conditioning unit events, the LOP events caused by a trip of a condensate drain line switch. The method also includes analyzing the detected pattern for at least one of a frequency of LOP events in a predetermined time period and an elapsed time between successive LOP events, and initiating a condensate line blockage alert when the analyzed pattern meets predetermined condensate line blockage criteria.

Abstract: A method for controlling operation of a fuel-fired heating appliance having a burner, a fuel flow control for controlling a fuel flow to the burner, and a combustion air blower for supplying combustion air to the burner, includes iteratively (1) determining the quality of combustion by sensing a flame at the burner and outputting a time-varying flame current signal that includes an ionization signal from the flame; sampling the flame current signal to obtain a time record of the flame current signal; using a Fourier transformation, transforming the time record into a frequency spectrum of frequency components that include frequency components of the ionization signal, the frequency spectrum having a spectrum shaped defined by various frequency components of the flame current signal; and determining whether the frequency spectrum indicates flame stability or instability.

Abstract: A monitoring system for monitoring a heating, ventilation, and air conditioning (HVAC) system of a building is provided. The monitoring system includes a monitoring server and a monitoring client. The monitoring server is configured to receive an aggregate current value from a monitoring device, wherein the aggregate current value represents a total current flowing through the HVAC system, determine a commanded operating mode of the HVAC system in response to the aggregate current value, wherein operating modes of the HVAC system include at least one of an idle mode and an ON mode, and analyze a system condition of the HVAC system based on the determined commanded operating mode. The monitoring client is configured to command the monitoring server to execute validation testing based on data received from monitoring the HVAC system, display results of validation testing, display real-time system performance data, and display an alert during a system malfunction.

Abstract: A method of operating a heating, ventilation, or air conditioning (HVAC) monitoring system includes, at a remote monitoring apparatus, receiving and storing frames of data from a local monitoring device installed at a building. Each of the frames includes time domain current data based on a measured aggregate current supplied to a plurality of components of an HVAC system of the building and frequency domain data based on the measured aggregate current. The method includes, based on the frequency domain current data and exclusive of individual current data from a plurality of individual current sensors, determining an individual contribution of a first component of the HVAC system to the measured aggregate current. The method includes transmitting information based on the stored current data to an HVAC manufacturer. The method includes, if a problem is identified with the first component using the determined individual contribution, transmitting an alert message.

Abstract: A monitoring system for a heating, ventilation, and air conditioning (HVAC) system of a residence includes a monitoring device installed at the residence and a server located remotely from the residence. The monitoring device measures an aggregate current supplied to a plurality of components of the HVAC system and transmits current data based on the measured aggregate current. The server receives the transmitted current data and, based on the received current, assesses whether a failure has occurred in a first component of the plurality of components of the HVAC system and assesses whether a failure has occurred in a second component of the plurality of components of the HVAC system.

Abstract: A powered anode current drive device is configured to automatically determine an anode drive current that offsets galvanic corrosion in a vessel. A method alerts a user on a change of an output of a powered anode current drive device. The method includes receiving an anode drive level output of the powered anode current drive device, determining electrical characteristics of the anode drive level output, analyzing the determined electrical characteristics for anomalous behavior, and generating an alert of the anomalous behavior.

Abstract: A system and methods of controlling a powered anode are disclosed. The method includes varying an electrical power input driving the powered anode through a range of values of a first electrical parameter, the range defined by an upper range limit and a lower range limit and measuring a current value of a second electrical parameter of the electrical power input during the varying. The method also includes determining a slope between the measured current values of the first and corresponding second electrical parameters and measured previous values of the first and second electrical parameters and comparing the determined slope to a predetermined slope threshold range and applying the current value of a first electrical parameter to the electrical power input when a discontinuity in the slope is determined.

Abstract: A circulator blower controller for a circulator blower of a heating, ventilation, and air conditioning (HVAC) system of a building includes an interface configured to receive a demand signal with an operating mode from a thermostat. A switching circuit selectively connects power to a tap of a motor of the circulator blower. A data store configured to store a mapping from a speed to the tap. For each tap, a processor observes power consumed by the circulator blower while power is connected to the tap by the switching circuit. The processor determines the mapping by sorting the taps based on observed power consumption. The processor selects a first speed based on the demand signal from the thermostat. The processor identifies a first tap from the mapping based on the first speed and generates the tap selection signal to control the switching circuit to connect power to the first tap.

Abstract: A monitoring system for an HVAC system of a building includes a monitoring server located remotely from the building. The monitoring server receives, from a device installed at the building, (i) time-domain current data based on a measured aggregate current supplied to a plurality of components of the HVAC system, and (ii) data based on frequency-domain current data of the measured aggregate current. Based on the received data, the monitoring server accesses (i) whether a failure has occurred in a first component of the plurality of components and (ii) generates a preliminary advisory in response to determining that the failure has occurred. The monitoring server compares the preliminary advisory to a threshold value based on data stored from prior advisories. If the preliminary advisory is on a first side of the threshold value, the monitoring server provides the preliminary advisory as a first advisory to a technician for review.

Abstract: A monitoring system for a heating, ventilation, and air conditioning (HVAC) system of a residence includes a monitoring device installed at the residence and a server located remotely from the residence. The monitoring device measures an aggregate current supplied to a plurality of components of the HVAC system and transmits current data based on the measured aggregate current. The server receives the transmitted current data and, based on the received current, assesses whether a failure has occurred in a first component of the plurality of components of the HVAC system and assesses whether a failure has occurred in a second component of the plurality of components of the HVAC system.

Abstract: A method of operating a heating, ventilation, or air conditioning (HVAC) monitoring system includes, at a remote monitoring apparatus, receiving and storing frames of data from a local monitoring device installed at a building. Each of the frames includes time domain current data based on a measured aggregate current supplied to a plurality of components of an HVAC system of the building and frequency domain data based on the measured aggregate current. The method includes, based on the frequency domain current data and exclusive of individual current data from a plurality of individual current sensors, determining an individual contribution of a first component of the HVAC system to the measured aggregate current. The method includes transmitting information based on the stored current data to an HVAC manufacturer. The method includes, if a problem is identified with the first component using the determined individual contribution, transmitting an alert message.

Abstract: Disclosed are exemplary embodiments of apparatus and methods for adjusting controller set points based on outdoor temperature. In an exemplary embodiment, a climate control system controller for providing climate control in a structure includes a processor and memory configured to obtain adjusted heating and cooling set point values determined by combining adjustment amounts with heating and cooling set points set for the climate control system. The adjustment amounts are determined in accordance with deviations of sensed outdoor ambient temperature (OAT) values from an intermediate OAT value predefined in a range of OAT values. The controller, in response to sensed outdoor temperatures in the range of OAT values, controls heating and cooling in the structure in accordance with the adjusted heating and cooling set point values.

Abstract: A monitoring system for a heating, ventilation, and air conditioning (HVAC) system of a building includes a monitoring device installed at the building, a monitoring server located remotely from the building, and a review server. The monitoring device measures an aggregate current supplied to components of the HVAC system and transmits current data based on the measured aggregate current. The monitoring server receives the transmitted current data and, based on the received current data, assesses whether failures have occurred in first and second components of the HVAC components. The monitoring server generates a first advisory in response to determining that the failure has occurred in the first component. The review server provides the first advisory to a technician for review and, in response to the technician verifying that the failure has occurred, transmits a first alert.

Abstract: A monitoring system for a heating, ventilation, and air conditioning (HVAC) system of a residence includes a monitoring device installed at the residence and a server located remotely from the residence. The monitoring device measures an aggregate current supplied to a plurality of components of the HVAC system and transmits current data based on the measured aggregate current. The server receives the transmitted current data and, based on the received current, assesses whether a failure has occurred in a first component of the plurality of components of the HVAC system and assesses whether a failure has occurred in a second component of the plurality of components of the HVAC system.

Abstract: A monitoring system for monitoring a heating, ventilation, and air conditioning (HVAC) system of a building is provided. The monitoring system includes a monitoring server and a monitoring client. The monitoring server is configured to receive an aggregate current value from a monitoring device, wherein the aggregate current value represents a total current flowing through the HVAC system, determine a commanded operating mode of the HVAC system in response to the aggregate current value, wherein operating modes of the HVAC system include at least one of an idle mode and an ON mode, and analyze a system condition of the HVAC system based on the determined commanded operating mode. The monitoring client is configured to command the monitoring server to execute validation testing based on data received from monitoring the HVAC system, display results of validation testing, display real-time system performance data, and display an alert during a system malfunction.

Abstract: A method of operating a heating, ventilation, or air conditioning (HVAC) monitoring service is described. The method includes: providing a local device for installation in an HVAC system of a residential or commercial building; periodically receiving data from the local device across a wide area network, wherein the received data includes electrical sensor data including at least one of current or power; and storing the received data. The method further includes: analyzing the stored data to selectively identify problems and selectively predict faults of the HVAC system; receiving a subscription fee corresponding to the building, the subscription fee applying to a calendar period; and during the calendar period, providing information on the identified problems and the predicted faults to a customer corresponding to the building.

Abstract: A monitoring system for a heating, ventilation, and air conditioning (HVAC) system of a building includes a monitoring device and a server. The monitoring device is installed at the building. The monitoring device (i) measures an aggregate current supplied to a plurality of components of the HVAC system and (ii) transmits current data based on the measured aggregate current. The server is located remotely from the building. The server receives the transmitted current data and, based on the received current, assesses whether a failure has occurred in a first component of the plurality of components of the HVAC system and assesses whether a failure has occurred in a second component of the plurality of components of the HVAC system.