Month: July 2015

What’s the difference between a water cooled chiller and air cooled chiller?

chiller

An air-cooled chiller has a condenser that is cooled by the environment air. The air-cooled chillers are preferred for small or medium installations but lately the quality improvement in their structure, allows the usage, in modular type, for large installations also. An air-cooled chiller is preferred especially in cases that there is not enough water or the water is very expensive. The water-cooled chillers have water cooled condenser connected with cooling tower and are usually preferred for medium and large installations where there is sufficiency of water. In addition, they are also preferred in cases that is demanded constant performance of the system, independently of the ambient temperature (industrial air conditioning, air conditioning of digital systems etc), because the capacity of the water-cooled chillers are not affected by the ambient temperature fluctuations.

A commonly asked question is what chiller is the best, air cooled or water cooled. The answer to that question is that there is no one perfect chiller for all applications. There are many aspects that come into effect when choosing what chiller would be best for a building and its cooling system.

Space is one of these issues. Air cooled chillers can utilize open space, such as a parking lot, roof or ground level area. Water cooled chillers are smaller in size, but require a mechanical room and cooling towers. On the flip side, air cooled chillers can have serious issues with recirculation if there are walls higher than the unit or too many units to close together. If there is a situation where outside walls are required for building code and the unit will not be receiving enough fresh air, then a water cooled application may be the best option.

Sound is another issue than may come into the equation. With any chiller sound is inevitable, air cooled chillers generally have a different decibel because of their fans. There are things that can be done to reduce the sound on chillers, but the best way to negate the sound is to purchase a quieter unit upon decision.

When it comes time to install a new chiller, these points should help in that field. There are many advantages and disadvantages to both kinds of chillers and some of those are listed below:

Air Cooled Advantages                                 

  • Install cost is generally lower
  • Less Maintenance depending on application
  • No need for a mechanical room
  • Cooling Tower not needed
  • Condenser pumps not required

 

Water Cooled Advantages

  • Usually have a longer life
  • Higher efficiency
  • Indoor placement
  • Larger tonnage capabilities
  • Refrigeration containment

 

Air Cooled Disadvantages

  • Generally less efficient
  • Life span is not as long
  • Usually have more operating noise

 

Water Cooled Disadvantages

  • Additional maintenance costs
  • Water treatment costs
  • Mechanical room needed

Whaley Unveils WHALE-SOFT™ – All New Elaborate Equipment Testing & Quality Standards System

After many months of planning, March 2015 marked a monumental moment in the history of Whaley Products, Inc.  A new era of Whaley equipment quality and consistency emerges as WHALE-SOFT™ Testing Software was launched and became a standard manufacturing procedure.

Whaley describes its new testing system to include the following procedures:

  • Each chiller system receives the following tests to ensure quality & consistency:

o   Test #1:  The chiller system’s refrigerant circuit is vacuum tested for 4 hours to negative PSIG pressure.

o   Test #2:  The chiller system’s refrigerant circuit is nitrogen tested to a minimum of 40psi for at least 30 minutes to confirm it is leak-free.

  • If a leak is found, the leak is repaired, and a new 30 minute nitrogen leak test is completed until a successful 30 minute nitrogen leak test is achieved.

o   Test #3:  The chiller system’s hydronic circuit is ran through a simulated WATER ONLY circulation loop at its rated flow rate for 5 minutes.

  • If a leak is found, the leak is repaired, and a new 5 minute leak test is completed until a successful 5 minute leak test is achieved.

o   Test #4:  The complete chiller system is ran through a simulated heat load circulation loop for 10 minutes to confirm the chiller system cools the loop sufficiently.  If the chiller system is a dual circuit system (20ton chiller with 2each 10ton refrigerant circuits), then each refrigerant circuit is tested for 10 minutes independently to confirm that each of the refrigerant circuits are functioning properly.

  • There are two separate heat load run testing stations.  The difference in the two is the type of heat transfer fluid the client’s chiller system will utilize.  The first is for straight-water applications only, and the second is for glycol applications.  A food-grade propylene glycol is utilized in the glycol testing station, and is maintained at 45% to 50% at all times.  If a client desires for their unit to be tested down to a specific fluid temperature, Whaley runs the chiller system or longer than 10minutes (if necessary), to achieve the lower fluid temperature.  The minimum for water is 40 degF, and the minimum for glycol is 10 degF, for standard R-410A refrigeration systems.  Whaley also offers alternative refrigerant systems for lower than 5F leaving glycol temperature.

A microprocessor interface is utilized in order to receive test data from a variety of sensor input from the simulation circulation test loops.  The test data streams live in the WHALE-SOFT™ Testing Software environment, and testing certificates in addition to start/end image screen shots of the software showing time stamps are provided to the customer for proof that their equipment was fully tested, demonstrating its full functional operation.

Below you will see an example of the WHALE-SOFT™ Testing Software interface.

whaley