In High pressure natural circulation boilers the flue gases flow through the following boiler accessories :
1. Superheater
2. Air-preheater
3. Economizer
4. I.D. fan
The correct sequence of the flow of flue gases through these boiler accessories is :
1
1, 3, 4, 2
2
3, 1, 4, 2
3
3, 1, 2, 4
4
1, 3, 2, 4