EVAPORATIVE CONDENSERS – COLD WEATHER CONSIDERATIONS
There are two problems that must be considered if a system is to be operated in
• keeping the water from freezing, if periods of extremely cold weather
• maintaining adequate head pressure to ensure refrigerant flow to the
If properly sized, an evaporative condenser can be operated dry in the winter to
prevent freezing and maintain head pressure. Other options to prevent freeze-ups are shown in figure below. The problem of maintaining satisfactory head pressure with a
condenser can be resolved by means of various control methods. For example, fan operation can be controlled by a switch that is actuated by the temperature of the spray water or the leaving air. Another method makes use of an air bypass assembly, with the by-passed air controlled by a motorized damper that is actuated by the temperature of the spray water or the leaving air. In addition to these control methods, it is possible to use a Winterstat® valve to bypass the refrigerant travel in the condenser.
Methods of avoiding a freeze-up.
The previous information is from Technical Institute Manual #3 available from The Refrigeration Service Engineers online store. RSES.org