What term describes a self-contained appliance for supplying steam or hot water?

The term that describes a self-contained appliance for supplying steam or hot water is "boiler, low pressure." A boiler is specifically designed to heat water and produce steam through the combustion of fuel or through electrical heating. It operates under a system that contains water and pressure, making it capable of providing both steam and hot water to various heating systems, including radiators and underfloor heating.

The term "low pressure" indicates that the boiler operates within specific pressure limits, which is crucial for safety and efficiency in residential and commercial applications. These appliances are integral to heating systems, especially in settings where a significant quantity of hot water or steam is required for heating spaces or processes.

Other terms like "furnace," "heat exchanger," and "water heater" refer to different types of heating equipment. A furnace primarily generates warm air for heating spaces, while a heat exchanger is a device used to transfer heat between two or more fluids without mixing them. Although a water heater provides hot water, it typically doesn't produce steam and may not be classified as a self-contained unit in the same way a boiler is.