ChillerMax

A New Approach to Maintaining Chiller Efficiency

Importance of Maintaining Chiller Efficiency

• Centrifugal water chillers can account for 20% to 40% of a facility’s total energy consumption.
• Centrifugal water chillers can lose as much as 30% efficiency and still appear to be operating satisfactorily.

Cost of Inefficiency

10,000 Ton Chiller Plant:

• Average cost to run chillers = $1,170,000
  (Assumptions: .65kw/ton, $0.06/kwh, 3,000 EFLH)
  
• Assuming 15% efficiency loss = $1,345,500

$175,500 in Wasted Energy!

Reality of Chiller Plant Operation

• Chiller logs are routinely taken, but analysis of the data is difficult and problems may not be identified in a timely manner.
• In many plants, the assumption is made that if the chiller is running and the building is cool, everything is OK.

Typical Chiller Maintenance Program

• Periodic logging using clipboard and log sheet
• BAS monitoring of:
  • Condenser water temperatures
  • Chilled water temperatures
  • Amps
• Routine periodic and annual maintenance

Log Readings Alone Are Not Efficient

• On the surface, chillers appear to be reliable and putting out a consistent supply of chilled water.

• A well-constructed chiller log sheet can reveal problems that cost you money.
  

• For example, this log sheet was taken at a chiller plant with over 40,000 tons of chiller capacity. Periodic logging has not identified an obvious problem.
  
  

ChillerMax: The High-Tech Solution

• Operator visits all operating chillers and collects data on a daily basis.
• Operator hot syncs with the website for chiller report.

Or…

• Using Autolog, log data can be entered directly from a BAS system.
• Problems are identified and quantified by source.
• Corrective actions are given and scheduled.
• Efficiency is restored or maintained.

ChillerMax Monitors Performance

• Easy data entry using PDA simplifies logging while adding value to the process.
  

ChillerMax Identifies Problems

• Fouled condenser or evaporator tubes
• Loss of refrigerant charge
• Cooling tower problems
• Water flow problems
• Non-condensables in the chiller
• Incorrect chill water or condenser water temperature set points

ChillerMax: Easy to Use

ChillerMax Dashboard

ChillerMax: Provides Solutions

Review the possible solutions to the problems indicated. If necessary, discuss with subcontractor such as water treatment or mcehanical services contractor.

Logsheet View

ChillerMax: Looks at Trends

Condition Based Maintenance

• Maintenance tasks assigned based on need, not an arbitrary schedule such as:
  • Tube brushing
  • Leak testing
  • Oil changes.
• Can result in significant reduction in annual maintenance costs.

Example: Emory University

• Chiller “annual maintenance” costs reduced by identifying tasks based on operational parameters.
• Condenser tube brushing reduced from 38 chillers per year to 15 in 2003 and 8 in 2005.
• Only one oil change required in 2003.

Cleaning Internally Enhanced Tubes

Internally Enhanced Tubes

• Spiral grooves
• Expanded tube surface

Dirty Tube
(Microbiological Fouling)

Lessons Learned

Two-Direction Versus Single-Direction Tube Brushing

ChillerMax Identifies Problem

ChillerMax Restores Efficiency

Lessons Learned with Internally Enhanced Tubes

Brush with a cleaning machine using dual rotation action

Use a brush designed for internally enhanced tubes

Change brushes as required, use a bore scope to inspect tubes

Connection End Heads

A Tube Sheet, or a Full Flow Filter?

For additional information contact:

Don Tomovich
302-753-7940
[email protected]