The condenser is the mirror image of the evaporator: the evaporator takes in heat, the condenser gives it off. Vapour arriving from the compressor at 60–80 °C passes through finned tubes, gives its heat to the outside air blown by the fans and condenses into liquid. The heat it rejects is the sum of the heat removed from the room and the electricity consumed by the compressor; so the condenser is always sized larger than the evaporator.
The air-cooled condenser is the most common type: fan-driven, placed outdoors or on the roof. A housed condenser is a model whose fan and body are enclosed to run quietly; it is preferred in residential areas and around supermarkets. In large plants evaporative (water-spray) or water-cooled condensers give a lower condensing temperature.
Condenser capacity is chosen for the highest summer ambient temperature; the catalog value is given for 32 °C ambient and a stated condensing temperature, and at 40 °C the capacity falls by about 20%. If the condenser is undersized or gets dirty, condensing pressure rises, the compressor struggles, capacity drops and electricity consumption rises; the high-pressure switch shuts the system down.
The most important maintenance job is keeping the fins clean: dust, pollen and poplar fluff cut capacity seriously within a few months. The condenser should be placed in the shade, where air flow is unobstructed and the hot air cannot recirculate onto itself. Our condenser and housed condenser models are listed in the catalog with capacity tables.