Heating and hot water supply system

A heating and hot water supply system, comprising:

• a combustion unit that combusts a fuel to generate a combustion gas;
• a heat exchange unit that heats a heat medium for heating and hot water for hot water supply according to exchange of heat with the combustion gas;
• and
• an exhaust unit that exhausts the combustion gas after heat exchange,
• wherein the heat exchange unit includes a plate type heat exchanger formed by laminating a plurality of vertically upright rectangular plates with gaps therebetween, and is configured to heat the heat medium for heating by causing the combustion gas and the heat medium for heating to alternately flow through the plurality of gaps of the plate type heat exchanger, and
• an inlet for the heat medium for heating is provided at a lower corner part of the plate type heat exchanger, a discharge opening for the heat medium for heating is provided at an upper corner part farthest from the inlet, and a hot water passage for hot water supply through which the hot water for hot water supply flows only in a plate lamination direction in the plate type heat exchanger is provided at an upper corner part on the side above the inlet, but not flows in the gaps between the vertically upright rectangular plates.