摘要 |
<p>A heating system for a building comprises a boiler and radiators to which hot water is supplied from the boiler, in which at least some of the return water flow from the radiators, typically at 6° C., circulates through a first heat exchanger to cool the exhausting products of combustion, means is provided to direct a small part of the return water flow through at least one heat exchanger which gives up heat to the building and/or to the boiler heating the water for heating he building, to cool the diverted water to well below the dew point, and means is provided to supply the cooled water to a second heat exchanger through which the already cooled exhaust products of combustion have to pass after leaving the first heat exchanger, to achieve full condensation of the water vapour content of the products of combustion form the boiler.</p> |