GT5-Unofficial/main/java/gregtech/common/tileentities/boilers
..
GT_MetaTileEntity_Boiler.java
GT_MetaTileEntity_Boiler_Bronze.java
GT_MetaTileEntity_Boiler_Lava.java
GT_MetaTileEntity_Boiler_Solar.java
GT_MetaTileEntity_Boiler_Steel.java