Refrigeration systems deteriorate silently: the condenser gets a little dustier every week, a flare connection leaks a few hundred grams a year, the contactor contacts blacken. As long as the room temperature is held nobody notices; the system simply runs longer and uses more electricity. The fault appears on the hottest day of the year, when the room is full. Periodic maintenance catches this decline by measurement; its cost is small beside a storeful of spoiled product or a burnt-out compressor.
The monthly and seasonal jobs are mostly visual: cleaning the condenser fins with compressed air or water (more often in a dusty environment and in the poplar fluff season), the frost and ice condition of the evaporator, the drain line being clear, the door gaskets and heaters, the noise and vibration of the fans, the oil level and moisture indicator in the sight glass, the alarm records in the controller. These checks can also be done by the business’s own staff. Every irregularity seen should be noted together with the date.
Once or twice a year a certified technician carries out maintenance with measurements: suction and discharge pressure, superheat, subcooling, discharge temperature, compressor and fan currents, the tightness of the electrical terminals, the contactor contacts, the pressure switch and safety settings, the current of the defrost heaters, an oil acid test and, if necessary, replacement of the filter drier. The leak check is carried out at a frequency that depends on the CO₂ equivalent of the charge under the F-gas regulation, and is recorded. The measured values are compared with those of the previous maintenance.
The value of maintenance lies in the record. If the same values are written on the same form at every visit, the trend becomes visible: a condensing temperature that has risen by 3 K compared with last year, or a compressor current that is slowly increasing, gives notice months before the failure. A remote monitoring system keeps this record automatically. The most suitable time is the spring months, before the summer load begins. For spare parts and suitable models you can consult our catalog, and for maintenance you can contact the Sonkar service network.