Using low-temperature NMR (¹H, ¹⁹F) technique in the slow exchange regime, the solutions containing tetrabutylammonium (TBA) acetate and HF have been studied in an aprotic freon mixture, CDF₃/CDF ₂Cl, exhibiting a dielectric permittivity, which increases strongly by lowering the temperature. Two different hydrogen bonded anionic clusters, a 1:1 cluster of the type AcO^δ-⋯H⋯F ^-1+δ+ ([AcOHF]^-) and a 2:1 cluster of the type AcOH⋯F^-⋯HOAc ([(AcOH)₂F]^-) have been detected in equilibrium with each other, both forming ion pairs with the TBA countercation. [AcOHF]^- exhibits an extremely strong hydrogen bond, with a proton shared between partially negatively charged oxygen and fluorine atoms. The NMR chemical shifts and scalar spin-spin coupling constants, ¹J(FH), have been measured in the temperature range between 110 and 160 K, where separate NMR signals are observed for both species. In addition, H/D isotope effects on the ¹⁹F NMR chemical shielding have been measured for both clusters. In contrast to the related complexes [(FH) _nF]^- (n=1-4) studied previously, the NMR parameters of [AcOHF]^- and of [(AcOH)₂F]^- depend strongly on temperature. This effect is associated with the increasing polarity of the solvent with decreasing temperatures, established earlier, which displaces the proton from fluorine to oxygen. As a motive power of this conversion, preferential solvation of the compact fluoride ion as compared to acetate is proposed.