1. Industrial Resources, Inc.
A TRAINING SERVICES COMPANY
Chiller System
Training Programs
Click to Start Program

2. INDUSTRIAL RESOURCES, INC.
Chiller System
Training Program
Module 11
CHILLED WATER SYSTEM
© Industrial Resources, Inc.

3. OBJECTIVES
State from memory the functions of the Chilled Water System.
Describe how the Chilled Water System operates, and where it is located, used and maintained.
List the normal operating parameters of the Chilled Water System.

4. FUNCTION
The Chilled Water System circulates chilled water for air conditioning, temperature sensitive equipment, and other cold water applications.

5. BASIC SYSTEM DESCRIPTION
A chilled water system consists of chilled water pumps, sand filters, isolation valves, and chillers that range in capacity.
Water typically leaves the chillers at 39oF and reenters the chiller plant at approximately 55oF.
Chilled water is pumped through various sizes of piping to the operating cooling equipment.

6. SYSTEM FLOW PATH Typical System Flow Path
This drawing Illustrates a typical flow path of a chilled water system. Returning Chilled Water passes through the operational chilled water pumps. Chilled Water Pumps that are not operating are valved out to prevent flow through the pump. A portion of the Chilled Water Return is directed through the sand filter to remove particulates from the water. The majority of the water is directed to the Chillers, where the water is cooled back down to the chilled water supply setpoint. The chilled water is then directed to the loads at the plant and those on the Chilled Water Supply Distribution system. Chillers and Chilled Water Pumps are enabled and disabled, as required by the load on the system. At peak load all of the Chillers and Pumps are operating, as the load reduces, chillers and pumps are removed from service.
Typical System Flow Path

7. SYSTEM FLOW PATH
The returned water enters the chilled water pumps at the flow setpoint.
At the chilled water pumps’ outlets the water flows to the chiller evaporator inlets.
In the evaporators, the water is chilled to 39°F and exits the evaporator outlets at the required pressure and flow rate.
The water exiting the evaporators flows out to the campus and is also distributed in-plant.
Water returned from the Power Plant is combined with water returned from the in-plant users, and completes the loop as it is fed back into the chilled water pumps.

8. SYSTEM MAJOR COMPONENTS
Objectives:
Describe how the chilled water system components operate.
State from memory, the names and purposes of the major components of the chilled water system.
Describe the locations of the chilled water system components.
Describe how and from where the chilled water system is controlled.
Objectives:
Describe how the chilled water system components operate.
State from memory, the names and purposes of the major components of the chilled water system.
Describe the locations of the chilled water system components.
Describe how and from where the chilled water system is controlled.

9. SYSTEM MAJOR COMPONENTS
Major components of the chilled water system
Chilled water pumps
Chiller evaporators
Isolation valves
Chilled water sand filter
Control Panel
Major components of the chilled water system
Chilled water pumps
Chiller evaporators
Isolation valves
Chilled water sand filter
Control Panel

10. CHILLED WATER PUMPS
The Chilled Water Pumps pump chilled water through the Chilled Water System.
The pumps receive water that has been used in air conditioners and other chilled water applications throughout the distribution network.
The returning water is approximately 55ºF and propelled through the pumps to the chiller evaporators.
The pumps push the water through the evaporators where it is chilled and distributed to the various loads in the system.
At the other end of the loop, the pumps receive the returning water, which has lost its chill, and send it through the evaporators to start the process all over again.

11. CHILLED WATER PUMPS
The Variable Frequency Drive (VFD) controls the pumps to maintain constant pressure regardless of environmental and load conditions.
The chilled water pumps can also be operated independently as necessary to assist in recovering refrigerant and other maintenance purposes.
The chilled water pumps supply the chillers.
The number of pumps running at any given time depending on the number of chillers running, pumps shut down for maintenance, and demand for chilled water on campus.

12. CHILLER EVAPORATORS
The evaporator is a shell and tube, flooded type heat exchanger.
A distributor trough provides uniform distribution of refrigerant over the entire shell length.
Stainless steel mesh eliminators (or suction baffles) are located above the tube bundle to prevent liquid refrigerant carryover into the compressor.
A liquid level sight glass is located on the side of the shell to aid in determine proper refrigeration charge.
The evaporator contains dual refrigerant relief valves. Return water is pumped in by the chilled water pumps at a temperature of approximately 55°F. The water is chilled by the tube bundle in the evaporator and exits to the power plant and in-plant users at 39°F.

13. ISOLATION VALVES
The isolation valve mounted in line with each chiller controls the water flow entering the chilled water system from the chiller evaporator.
The isolation valves are pneumatically actuated valves controlled by the VFD to maintain the most efficient flow of water from the chillers.
The isolation valve mounted in line with each chiller controls the water flow entering the chilled water system from the chiller evaporator.
The isolation valves are pneumatically actuated valves controlled by the VFD to maintain the most efficient flow of water from the chillers.

14. CHILLED WATER SAND FILTER
A side stream of the pipes in the line from the chilled water pumps diverts some of the water in the chilled water closed loop to the chilled water sand filter.
The sand filter removes the bulk of solids and circulating bio-films from the closed loop chilled water system
While the closed loop means the chilled water is circulated through the system with as little loss as possible and little makeup water required to replenish the system.
Filtering the water through the sand filter reduces water loss and damage to the piping and equipment.
Reduced water loss also reduces added O2, which is a major cause of corrosion in a closed loop system.
A side stream of the pipes in the line from the chilled water pumps diverts some of the water in the chilled water closed loop to the chilled water sand filter.
The sand filter removes the bulk of solids and circulating bio-films from the closed loop chilled water system
While the closed loop means the chilled water is circulated through the system with as little loss as possible and little makeup water required to replenish the system.
Filtering the water through the sand filter reduces water loss and damage to the piping and equipment.
Reduced water loss also reduces added O2, which is a major cause of corrosion in a closed loop system.

15. DISTRIBUTED CONTROL SYSTEM (DCS) CONTROL PANEL
The DCS control panel is a screen of the Direct Digital Control (DDC) work station located in the control room. This screen is used to monitor operation of the chilled water and condensed water system, display alarms, and control events. This screen provided a graphical display of all components of the system and their operation in real time.

16. APPLICATION Objectives:
Describe the proper operation of the chilled water system.
The chilled water system is a closed loop system that distributed chilled water to the campus and in-plant users and collects the returned water to be chilled again.
This provides an economical, efficient, and environmentally responsible solution for campus air conditioning and chilled water applications.
After the water completes its circuit through the campus buildings, it returns to the chiller stations where the warmed water (approximately 49ºF) is pumped by the chiller water pumps back to the chiller evaporators, where the water is processed and the temperature reduced to 39ºF.
Objectives:
Describe the proper operation of the chilled water system.
The chilled water system is a closed loop system that distributed chilled water to the campus and in-plant users and collects the returned water to be chilled again.
This provides an economical, efficient, and environmentally responsible solution for campus air conditioning and chilled water applications.
After the water completes its circuit through the campus buildings, it returns to the chiller stations where the warmed water (approximately 49ºF) is pumped by the chiller water pumps back to the chiller evaporators, where the water is processed and the temperature reduced to 39ºF.
References
Associated System P&ID, Logic or E-Drawings, and Equipment Technical Manuals

17. PURPOSE
This procedure provides information and guidance for the correct and safe operation of the Chilled Water System.
Prior to operating the equipment, you must understand the operating parameters of the chilled water system.
The system, comprised of four chilled water pumps, three chiller evaporators, three isolation valves, and one chilled water sand filter, supplies chilled water to the campus along with the other three chiller stations.
The chilled water system also supplies chilled water to for in-plant distribution users and the inlet air cooling system.

18. PRECAUTIONS, LIMITATIONS AND SETPOINTS
Observe all facility safety rules and precautions when handling chemicals or performing any other hazardous tasks.
Don the appropriate level of Personnel Protective Equipment (PPE) when completing tasks involving the York Chillers.
All switching and tagging will be performed in accordance with approved Switching and Tagging Instructions.
Verify all maintenance work is completed and all tags are cleared and removed.
Verify power is available to chilled water system components.
Report any chemical leak, take proper precautions, and secure the leaking equipment.
Use proper cleanup procedures.
Observe all facility safety rules and precautions when handling chemicals or performing any other hazardous tasks.
Don the appropriate level of Personnel Protective Equipment (PPE) when completing tasks involving the York Chillers.
All switching and tagging will be performed in accordance with approved Switching and Tagging Instructions.
Verify all maintenance work is completed and all tags are cleared and removed.
Verify power is available to chilled water system components.
Report any chemical leak, take proper precautions, and secure the leaking equipment.
Use proper cleanup procedures.

19. PROCEDURE Chilled Water System Start-Up
Perform a thorough walk down of chilled water system equipment.
Verify isolation valves are open.
Verify chillers and related systems are available.
Verify oil levels are sufficient for operation.
Remove any tagging, maintenance equipment, scaffolding, and any non-essential equipment that may interfere with operation of the chilled water system.
Verify the electrical supply to the system is energized.
Verify the system equipment is properly aligned for normal operation and flow.
Chilled Water System Start-Up
Perform a thorough walk down of chilled water system equipment.
Verify isolation valves are open.
Verify chillers and related systems are available.
Verify oil levels are sufficient for operation.
Remove any tagging, maintenance equipment, scaffolding, and any non-essential equipment that may interfere with operation of the chilled water system.
Verify the electrical supply to the system is energized.
Verify the system equipment is properly aligned for normal operation and flow.

20. CHILLED WATER STATION NORMAL OPERATION
At regular intervals, walk down the chilled water system inspecting for leaks, abnormal equipment noise and temperatures, water flow, and lubrication levels.
Regularly monitor the Optimum Energy screen on the DDC for unusual readings and alarms. Log any unusual activity.
Provide an informative turnover to the on-coming shift. Note any planned system changes, developing trends, and indications of potential problems.
At regular intervals, walk down the chilled water system inspecting for leaks, abnormal equipment noise and temperatures, water flow, and lubrication levels.
Regularly monitor the Optimum Energy screen on the DDC for unusual readings and alarms. Log any unusual activity.
Provide an informative turnover to the on-coming shift. Note any planned system changes, developing trends, and indications of potential problems.

21. CHILLED WATER SYSTEM SHUTDOWN
Shut down the chilled water pump(s) through the DDC in the control room.
Rack out the electrical supply.
Isolate discharge piping of the chilled water pump(s).
De-energize the affected equipment.
Perform Lock Out/Tag Out (LOTO) on the chilled water pump(s).
Shut down the chilled water pump(s) through the DDC in the control room.
Rack out the electrical supply.
Isolate discharge piping of the chilled water pump(s).
De-energize the affected equipment.
Perform Lock Out/Tag Out (LOTO) on the chilled water pump(s).
The following is a brief overview of the shutdown of the chilled water system. The actual tasks associated with shutdown are accomplished in conjunction with total unit shutdown.
References
Associated System P&ID, Logic or E-Drawings, and Equipment Technical Manuals

22. CHILLER WATER SYSTEM VALVE LIST

23. CONTROL PANEL SCREEN
Sample DCS Control Screen

24. SAMPLE CHILLER CONTROLLER SYSTEM SCREEN