THE MODEL FOR POWER EFFICIENCY ASSESSMENT OF CONDENSATION HEATING INSTALLATIONS

The main part of heating systems and domestic hot water systems are based on the natural gas boilers. For increasing the overall performance of such heating system the condensation gas boilers was developed and are used. However even such type of boilers don't use all energy which is released from a fuel combustion. The main factors influencing the lowering of overall performance of condensation gas boilers in case of operation in real conditions are considered. The structure of the developed mathematical model allowing estimating the overall performance of condensation gas boilers (CGB) in the conditions of real operation is considered. Performace evaluation computer experiments of such CGB during a heating season for real weather conditions of two regions of Ukraine was made. Graphic dependences of temperature conditions and heating system effectiveness change throughout a heating season are given. It was proved that normal CGB does not completely use all calorific value of fuel, thus, it isn't effective. It was also proved that the efficiency of such boilers significantly changes during a heating season depending on weather conditions and doesn't reach the greatest possible value. The possibility of increasing the efficiency of CGB due to hydraulic division of heating and condensation sections and use of the vapor-compression heat pump for deeper cooling of combustion gases and removing of the highest possible amount of thermal energy from them are considered. The scheme of heat pump connection to the heating system with a convenient gas boiler and the separate condensation economizer allowing to cool combustion gases deeply below a dew point and to warm up the return heat carrier before a boiler input is provided. The technological diagram of the year-round use of the heat pump for hot water heating after the end of heating season, without gas use is offered.