Here's how steam boilers can be used to produce hot water:

1. Indirect Heating: In an indirect heating setup, the steam produced by the boiler is used to indirectly heat a separate system of water, which then becomes hot water. This can be achieved through a heat exchanger. The steam does not directly come into contact with the water that is being heated for domestic or industrial use.

2. Dual-Purpose Boilers: Some boilers are designed to serve dual purposes, producing both steam and hot water. These boilers can be used for heating applications that require either steam or hot water.

3. Cascading Systems: In certain setups, steam can be converted into hot water by allowing it to release its heat energy to a water system. This might involve using steam to heat a tank of water, which then becomes hot water for distribution.

However, for most hot water applications, using dedicated hot water boilers or heaters is more common and efficient. Hot water boilers are specifically designed to heat water for domestic or industrial use directly, without the need for generating steam. These boilers operate at lower temperatures and pressures compared to steam boilers, which makes them more suitable for hot water production.

When choosing between a steam boiler and a hot water boiler, consider factors such as your specific hot water demand, efficiency requirements, ease of maintenance, and the overall cost-effectiveness of the system. Consulting with experts in the field of heating systems can help you make the best choice for your needs.