By the way of analysing the water flow design of several typical water heating systems, the paper introduces the basic request of the water flow design, and helps related people to understand the thinking for water flow design of the water heating system.

The composition of warm-air heating system using gas-fired unit heater as heat source in a separate house is introduced.

Taking a small natatorium in Tianjin for research object,the ventilation heating load of heating and ventilation system with hot blast and its ratio in total heating load in winter are calculated.

The existing problem in steam air heater & drainage system for No.

trofit of drainage system of steam air heater in fossil-fired power plant;