The ubiquitous coexistence of majority insulating 245 phases and minority superconducting (SC) phases in A(x)Fe(2-y)Se(2) (A = K, Cs, Rb, Tl/Rb, Tl/K) formed by high-temperature routes makes pure SC phases highly desirable for studying the intrinsic properties of this SC family. Here we report that there are at least two pure SC phases, KxFe2Se2(NH3)(y) (x approximate to 0.3 and 0.6), determined mainly by potassium concentration in the K-intercalated iron selenides formed via the liquid ammonia route. K0.3Fe2Se2(NH3)(0.47) corresponds to the 44 K phase with lattice constant c = 15.56(1) angstrom and Ka(6)Fe(2)Se(2)(NH3)(0.37) to the 30 K phase with c = 14.84(1) angstrom. With higher potassium doping, the 44 K phase can be converted into the 30 K phase. NH3 has little, if any, effect on superconductivity. Thus, the conclusions should apply to both K0.3Fe2Se2 and K0.6Fe2Se2 SC phases. K(0.3)Pe(2)Se(2)(NH3)(0.47) and K0.6Fe2Se2(NH3)(0.37) stand out among known superconductors as their structures are stable only at particular potassium doping levels, and hence the variation of T-c with doping is not dome-like.