Design Of Condensing Wall-hung Gas Boiler-floor Heating System And Study On The Effect Of Buffering Water Tank

With the rapid development of China's economy and the general improvement of people's living standards,environmental pollution has increasingly become an urgent problem to be solved,seriously affecting people's daily health and life.Therefore,the state has issued some relevant policies,among which the "coal to gas" policy is a current development trend.In recent years,the number of cold days in winter in southern China has increased significantly,and bad weather often occurs.The main manifestations are as follows:(1)the average outdoor temperature is significantly lower,the average monthly temperature of the coldest month is 0-10 degrees C,and even some areas have broken the historical extreme;(2)the temperature has decreased greatly,and the temperature lasts longer at the low end;(3)rainy,snowy,rainy and snowy days.The monthly average relative humidity is about 80%,which shows an increasing trend.The voice of heating in southern urban areas of China has shown a marked growth trend,and the voice of appeal has obviously increased.Especially in Hangzhou,where the economic living standard is relatively high in Zhejiang Province,the winter is wet and cold,the summer is muggy and hot,the humidity is high throughout the year,the indoor temperature in winter is low,and the comfort experience of residents is poor.In view of the above description,the independent heating system of condensing wall-mounted furnace-floor heating is selected as the research object after comprehensive consideration.The concept of energy saving and emission reduction has a long history.It has always been a national key environmental protection requirement,and vigorously advocates the use of clean energy.Because of its high efficiency,environmental protection and energy saving,condensing wall-hanging furnace has gradually become one of the development directions of heating sources.Natural gas has always been the representative of clean energy.The condensing wall-hanging furnace uses it as the combustion medium to recover sensible heat from the combustion flue gas and latent heat from the flue gas.Therefore,the thermal efficiency of the condensing wall-hanging furnace is obviously improved and the purpose of energy saving and emission reduction is achieved.Therefore,the condensing wall-hanging furnace isadopted in this research.According to the structure and function of condensing wall-hanging furnace,it is divided into three heating modes:heating only,heating system plus domestic hot water,heating system plus domestic hot water plus external water tank.Firstly,the condensing wall-mounted stove-floor heating system is introduced and systematically analyzed.Combining with an engineering example of a residential district in Binjiang District of Hangzhou City,the above three independent heating modes are compared,and the advantages and disadvantages of comfort under different modes are compared.Finally,the economic analysis of three heating modes is carried out.According to the characteristics of the three heating modes,this paper provides reasonable guidance for the designers and users of the independent household gas condensing wall-mounted furnace-floor heating system.The test results show that for the condensing wall-mounted stove-floor heating system without buffer tank,the starting and stopping frequency of the condensing wall-mounted stove is higher than that of the system with buffer tank.The first floor heating system only has heating system;the second floor heating system adds domestic hot water;the third floor heating system adds domestic hot water plus external water tank(buffer water tank).The indoor temperature of three condensing wall-mounted furnace-floor heating systems is tested,and the operation of the three systems is analyzed according to the test results.In the three heating modes,the single heating system starts and stops relatively frequently,but because the user area is relatively small,the effect is still possible.In the condensing wall-hanging furnace plus domestic hot water system,the starting and stopping period of the condensing wall-hanging furnace is shorter than that of the system with buffer water tank,and the starting and stopping period of the system with buffer water tank is longer.The room temperature is relatively stable because of the heat storage performance of the floor heating itself.The economic analysis of the system shows that the condensing wall-mounted furnace-floor heating system is cheaper than the air-conditioning heating system.