CONDENSATION HOT-WATER BOILER FOR EXTERNAL ARRANGEMENT Russian patent published in 2013 - IPC F24H1/00 

FIELD: heating.

SUBSTANCE: boiler includes a hydrothermoinsulated housing with a stack base, two heat exchangers, which are parallel connected as per a straight-flow downward scheme and made from various materials. External heat exchanger is made for example from carbon steel, and internal heat exchanger is made from noncorroding materials.

EFFECT: cheaper heat and higher condensation use effect both at natural, and forced circulation of heat carrier with preservation of the boiler operability at blackout.

2 cl, 1 dwg