Fluid to Fluid Heat Exchanger or Chiller? How to Choose?
This is a question that you may be asking yourself? Both units control temperature, however there are differences between a Chiller and a Heat Exchanger.
Let’s start with understanding the basic difference between a Chiller and a Heat Exchanger. Fluid to fluid heat exchangers do not have a refrigeration system. They are ideal when in-house water is either too cold, too dirty or does not have enough pressure to adequately support your water cooled equipment. The Heat Exchangers provide a clean stable, controlled closed-loop water cooling system. The fluid to fluid heat exchangers offer the advantage of removing heat from the circulating coolant (via a water to water heat exchanger) and transfer heat to either tap or facilities water. The actual temperature of the circulating coolant is controlled by a temperature controller and a solenoid valve. Due to varying water supplies, a gate valve is also used to regulate flow/pressure of the facility or house water supply.
What about Chillers?
Chillers are a little different. Chillers are available as either Air-Cooled or Water-Cooled models. The basic pieces and parts in a chiller (both air-cooled and water-cooled) are rather similar. Both contain a compressor, condenser, evaporator and an expansion valve. An air-cooled chiller removes the heat by blowing cool air on the condenser, thereby lowering the temperature.
A water-cooled chiller removes the heat by circulating cool water through the lines in the condenser. Chillers feature refrigeration systems and provide rugged, accurate and economical cooling. The Recirculating Chillers feature a compressor, CFC-free refrigerant and a hot-gas by-pass valve.
How Do Water Cooled Chillers & Air Cooled Chillers Work?
The process begins with the evaporator. A liquid refrigerant flows over the evaporator tube bundle and as it evaporates it absorbs heat from the water circulating through the bundle and creates a vapor. The compressor then forces the vapor out of the evaporator and in to the condenser. The vapor condenses on or in the condenser tubes, giving up its heat to the cooling water (or air). The high pressure liquid refrigerant from the condenser then passes through the expansion device that reduces the refrigerant pressure and temperature as it enters the evaporator. The refrigerant again flows over the chilled water coils absorbing more heat and completing the cycle.
Still Not Sure if I need a Fluid to Fluid Heat Exchanger or Chiller?
It is at this point you should contact a sales person. After you describe your process and needs, the sales person will be able to guide you to the best unit for your specific needs. You may if you desire size a chiller yourself using a simple, easy to follow formula. However, a sales person will be willing to answer your questions, confirm your calculations and guide you to the best unit for your requirements.