Abstract: An operation apparatus monitoring system includes an operation apparatus as a monitoring target. The operation apparatus includes a control part capable of executing control of acquiring multiple pieces of apparatus information associated with an operation status and periodically transmitting acquired data of the multiple pieces of apparatus information to a monitoring apparatus. In the control part, multiple groups are set, and data of the multiple pieces of apparatus information are grouped to belong to at least one of the multiple groups and are stored. Transmission of data of the multiple pieces of apparatus information to the monitoring apparatus is executed according to a sequence of data transmission to the monitoring apparatus determined for each group.

Abstract: When a voltage signal is input to input terminals as a positive voltage, the voltage conversion circuit generates a control voltage proportional to an input voltage by a voltage-dividing circuit according to resistance elements, a voltage follower circuit according to an operational amplifier, and a voltage-dividing circuit according to resistance elements. When a voltage signal is input to the input terminals as a negative voltage, since the operational amplifier outputs a power supply voltage according to an input of the negative voltage, the voltage conversion circuit generates a predetermined positive voltage obtained by dividing the power supply voltage by the resistance elements as the control voltage. The predetermined positive voltage is higher than a voltage range of the control voltage when the voltage signal is input as the positive voltage.

Abstract: When a hot water supply operation is started, a single mode is used in which hot water is output only from a second hot water supply circuit of a water heater, by cut-off of a flow path in a first hot water supply circuit of a space-heating water heater by a cut-off mechanism. When a load imposed by hot water supply by the second hot water supply circuit increases during the hot water supply operation in the single mode, the cut-off mechanism is opened to start hot water output from the first hot water supply circuit and a hot water supply operation in a parallel mode is performed in which hot water is output from both of the first hot water supply circuit and the second hot water supply circuit.

Abstract: In a heating and hot water supply apparatus, a heat exchanger for hot water supply includes a primary-side path and a secondary-side path. A bypass path branches from a heating circulation path and is configured such that a heat transfer medium heated by a heating device flows through the primary-side path without passing through a heating terminal when hot water supply operation is performed and then joins the heating circulation path again. A control unit controls a flow rate regulating valve so that a hot water flow rate does not exceed a reference limit flow rate when hot water supply operation is performed. The reference limit flow rate is set on the basis of the smaller one between a maximum heating capacity of the heating device and a heating capacity of the heating device at which an output temperature of the heated heat transfer medium reaches an upper limit temperature.

Abstract: A distribution valve controls a distribution ratio of a heat transfer medium between a hot water supply path including a heat exchanger for hot water supply and a beating circulation path through which the heat transfer medium is supplied to a heating terminal. A bypass flow rate control valve controls a bypass ratio which is a ratio of a flow rate of low temperature water introduced into a bypass pipe that bypasses the heat exchanger for hot water supply to a flow rate of low temperature water introduced into a water inlet pipe. The bypass ratio is regulated so that a hot water temperature detected by a temperature sensor reaches a hot water target temperature. During a simultaneous operation of hot water supply and heating, the distribution valve is controlled so that, when a bypass ratio is low, a distribution ratio is higher than when a bypass ratio is high.

Abstract: A solenoid valve driving apparatus includes switching means for ON/OFF-controlling application of a direct current voltage to a solenoid of a solenoid valve, and signal outputting means. A first period and a consecutive second period are set as a valve opening operation period of the solenoid valve. When the signal outputting means outputs the PWM signal to the switching means, a duty ratio of the output signal is set to be higher in the second period than in the first period so that a power supplied to the solenoid is larger in the second period than in the first period. As a result, a valve opening operation is performed in the solenoid valve reliably, and loud noise generation during the valve opening operation is suppressed.

Abstract: A distribution valve controls a distribution ratio of a heat transfer medium between a hot water supply path including a heat exchanger for hot water supply and a beating circulation path through which the heat transfer medium is supplied to a heating terminal. A bypass flow rate control valve controls a bypass ratio which is a ratio of a flow rate of low temperature water introduced into a bypass pipe that bypasses the heat exchanger for hot water supply to a flow rate of low temperature water introduced into a water inlet pipe. The bypass ratio is regulated so that a hot water temperature detected by a temperature sensor reaches a hot water target temperature. During a simultaneous operation of hot water supply and heating, the distribution valve is controlled so that, when a bypass ratio is low, a distribution ratio is higher than when a bypass ratio is high.

Abstract: In a heating and hot water supply apparatus, a heat exchanger for hot water supply includes a primary-side path and a secondary-side path. A bypass path branches from a heating circulation path and is configured such that a heat transfer medium heated by a heating device flows through the primary-side path without passing through a heating terminal when hot water supply operation is performed and then joins the heating circulation path again. A control unit controls a flow rate regulating valve so that a hot water flow rate does not exceed a reference limit flow rate when hot water supply operation is performed. The reference limit flow rate is set on the basis of the smaller one between a maximum heating capacity of the heating device and a heating capacity of the heating device at which an output temperature of the heated heat transfer medium reaches an upper limit temperature.

Abstract: When a voltage signal is input to input terminals as a positive voltage, the voltage conversion circuit generates a control voltage proportional to an input voltage by a voltage-dividing circuit according to resistance elements, a voltage follower circuit according to an operational amplifier, and a voltage-dividing circuit according to resistance elements. When a voltage signal is input to the input terminals as a negative voltage, since the operational amplifier outputs a power supply voltage according to an input of the negative voltage, the voltage conversion circuit generates a predetermined positive voltage obtained by dividing the power supply voltage by the resistance elements as the control voltage. The predetermined positive voltage is higher than a voltage range of the control voltage when the voltage signal is input as the positive voltage.

Abstract: When a hot water supply operation is started, a single mode is used in which hot water is output only from a second hot water supply circuit of a water heater, by cut-off of a flow path in a first hot water supply circuit of a space-heating water heater by a cut-off mechanism. When a load imposed by hot water supply by the second hot water supply circuit increases during the hot water supply operation in the single mode, the cut-off mechanism is opened to start hot water output from the first hot water supply circuit and a hot water supply operation in a parallel mode is performed in which hot water is output from both of the first hot water supply circuit and the second hot water supply circuit.

Abstract: A solenoid valve driving apparatus includes switching means for ON/OFF-controlling application of a direct current voltage to a solenoid of a solenoid valve, and signal outputting means. A first period and a consecutive second period are set as a valve opening operation period of the solenoid valve. When the signal outputting means outputs the PWM signal to the switching means, a duty ratio of the output signal is set to be higher in the second period than in the first period so that a power supplied to the solenoid is larger in the second period than in the first period. As a result, a valve opening operation is performed in the solenoid valve reliably, and loud noise generation during the valve opening operation is suppressed.