Hot water apparatus with flanged connections

A hot water apparatus comprising:

• a heat exchanger including a heat exchange portion and a first case in which the heat exchange portion is housed;
• and
• a housing including a second case connected to the first case of the heat exchanger,
• the first case of the heat exchanger including
• a first circumferential wall portion,
• a first opening provided at a lower end of the first circumferential wall portion, and
• a first flange portion located above the first opening and extending outward from the first circumferential wall portion,
• the second case of the housing including
• a second flange portion connected to the first flange portion,
• a second circumferential wall portion arranged inside the second flange portion, and
• a second opening provided at an upper end of the second circumferential wall portion,
• the first circumferential wall portion of the heat exchanger including a downwardly-extending wall portion that is inserted through the second opening of the housing into an inside of the second circumferential wall portion,
• in a state where the downwardly-extending wall portion is arranged inside the second circumferential wall portion, the first opening being located below an upper surface of the second flange portion,
• wherein the downwardly-extending wall portion is arranged such that a gap is interposed between the downwardly-extending wall portion and the second circumferential wall portion,
• the housing includes a connection portion connected to a lower end of the second circumferential wall portion,
• the connection portion extends toward an inside of the second circumferential wall portion, and is arranged such that a gap is interposed between the connection portion and a lower end of the downwardly-extending wall portion, and
• the gap between the downwardly-extending wall portion and the second circumferential wall portion is greater than the gap between the downwardly-extending wall portion and the connection portion.