Cycling losses in refrigeration equipment: An experimental evaluation

Cycling losses may be defined as those inefficiencies that reduce the performances of units during the transient period. They may be quantified by comparing the Energy Efficiency Ratio (EER) of a cycling unit and the EER of the same unit working continuously.The on-off control is the most widespread strategy for modulating; therefore, a reliable evaluation of cycling losses is fundamental to assess the EER of the system. The mentioned losses have been experimentally evaluated on a test rig, and logged data demonstrate a loss up to 13% with respect to steady operations when the load factor is lower than 10% and a Thermostatic Expansion Valve (TEV) is used. The insertion of a solenoid valve in series with the TEV can reduce the losses but the best results are obtained by using the Electronic Expansion Valve (EEV) instead of the TEV.