Remove top, sides and water tank carrier
A = Vent tube
B = solenoid coil (should move Nucleus, with spring and seal) up a tube
C= Might be bayonet fitting, or could be a nut you have to undo
Remove vent tube, then remove B, undo nut on left…slides off (remember which wires connected to what, or leave them on if you can). Then you will see if C is a nut, or part of a bayonet type tool less fitting. After removal of that tube, depending on the type of solenoid, you should be able to remove the nucleus. Check seat and sealing pad for debris and remove.
If it’s not a type with a nucleus, you may have to go for more disassembly. Take lots of photos to be able to ask for more guidance, if it’s not like I think. There are different ways this can be done.