In the project described in this paper an experimental rig for a one-stage absorption heat transformer was designed
and constructed. One aim of the project was to reduce the investment costs for the apparatus. This incorporates new and less
expensive compact brazed plate heat exchangers for generator, evaporator, condenser and solution heat exchanger. The absorber
was designed as a helical coil pipe absorber, where the weak solution trickles down as a falling film outside of the coil. The tests
of the equipment involved measurements using a mixture of trifluorethanol (TFE) and tetraethyleneglycoldimethylether (E181). The
process characteristics were investigated for different temperatures of the rich solution leaving the absorber. Experimental results are
presented and compared with the results of a computer simulation model. Additionally the model was used to compare the COP of the
heat transformation process with the mixtures lithium bromide–water (LiBr–H2O) and ammonia–water (NH3–H2O). Furthermore, the
overall heat and mass transfer coefficients for the plate heat exchangers and the falling film absorber were evaluated and compared
with those of shell and tube heat exchangers