Increasing Efficiency of a Condensing Boiler by Improving the Design and Operating Characteristics of the Consumer

Condensing boilers can achieve significantly higher efficiency than conventional ones due to possibility to recover latent heat of vaporization from the flue gas. But it can be achieved when return temperature of heating system is sufficiently low (below the dew temperature of the flue gas), which directly depends on thermal modes of the heat consumer. The work evaluates ways of increasing performance of a condensing boiler by implementing energy efficient solutions in buildings. It has been found that the biggest increase in boiler efficiency (by 6.6 %) can be achieved by switching to low-temperature heating systems. Applying intermittent heating is in second place in terms of the possibility of increasing boiler efficiency (up to 3.5 %). Insulation of the house also increases boiler efficiency, but less than the previous two solutions (up to 2.7%). Complex analysis has shown that reducing return temperature of the heating system by increasing heating area or using more efficient radiators, switching to intermittent heating and improving building insulation can increase the average seasonal efficiency of the condensing boiler by 8.8%. Seasonal natural gas consumption can be reduced by 69%.