CETIAT has accomplished measurements of a combined
brine-to-water heat pump using desuper¬hea¬ting of the compressed refrigerant.
Fig. 1 depicts the layout of the system. The system has the following operation
modes: space heating only and combined space heating and DHW production by
desuperheating. In addition, an electrical back-up heater is used, if there is
no space heating, during night times and if the maximum temperature of the
storage tank is less than 60°C.
The testing of the system has been performed according to existing standards and
standards being currently discussed or introduced: The single heating mode
according to EN 14511, CEN/TS 14825 for part load operation, EN 255-3 and
M/324 with the European reference tapping
cycles No.2. In conclusion, a test procedure for these types of heat pump
systems is proposed.
Fig. 1: Simultaneous brine-to-water heat pump of French
EdF has performed tests for part load operation of
an air-to-water heat pump in heating and in cooling mode at
different load ratios [5% to 100%], different capacities of the
distribution/emission system [11, 22, 33 l/kW] and different
settings of the hysteresis controller. Delivered results shall
serve as hints for the calculation method by providing
correction factors for part load operation.. Fig. 2 shows the
layout of the test rig for the part load testing.
Fig. 2: Layout of the test-rig for the testing of part-load
operation of an air-to-water heat pump