Boilers
Boilers are used to heat water for water-based heating systems such as radiant floors or radiators. They are also commonly used to provide the domestic hot water needs, as they can be quite efficient (up to 96% if using gas).
They are available in a variety of fuel types (wood, oil, and gas) and a variety of corresponding efficiencies.
Other devices commonly used instead of boilers are tankless water heaters and high efficiency tank-style water heaters. The tankless heaters are often used due to their lower upfront costs. The high efficiency tank heaters are commonly used if a tank is required for heat exchange from another system, like solar or geothermal.
