Abstract: A hot water supply device includes a combustion part, a combustion fan, a heat exchange part, a water supply part, a hot water discharge part, and a control part. In the hot water supply device, in a pre-purge step of a heating operation, the presence or absence of a disturbance factor is determined based on rotational responsiveness and deviation of the combustion fan with respect to a scavenging rotation speed. When there is no disturbance factor, in an ignition step, detection of a failure sign is performed based on responsiveness and deviation of the combustion fan with respect to an ignition rotation speed.

Abstract: A hot water supply device includes a combustion part, a combustion fan, a heat exchange part, a water supply part, a hot water discharge part, and a control part. In the hot water supply device, in a pre-purge step of a heating operation, the presence or absence of a disturbance factor is determined based on rotational responsiveness and deviation of the combustion fan with respect to a scavenging rotation speed. When there is no disturbance factor, in an ignition step, detection of a failure sign is performed based on responsiveness and deviation of the combustion fan with respect to an ignition rotation speed.

Abstract: Provided is a shell composition that is formed with a water-insoluble powder such as starch and/or a water-soluble polymer such as dextrin as a base component, and with locust bean gum and/or xanthan gum as a gelling agent. This shell composition enables a novel shell composition which can favorably form a shell without using carrageenan, has favorable properties that enable the shell composition to substitute traditional shells that use a gelatin shell or carrageenan, and comprises a plant-derived base.