1. https://facilitiesservices.utexas.edu/buildings/UTM/0448
Field Trip
Next Tuesday (May 2nd)
PPE 3.3
04 conference room at 11 am

2. Lecture Objectives: Finish with thermal storage systems
Learn about pumps and plumbing

3. Thermal storage system in parallel- requires stratified tanks

4. Stratified chilled water tanks diffuser geometry
Challenge:
“Pull” large amount of energy without
disturbing stratification

5. Temperature and dynamics
Temperature at outlet during the
changing cycle of the tanks

6. Installation of thermal storage system when in series
Upstream
Downstream
• Increases chiller efficiency
• Increases chiller capacity
• Overall system efficiency ???
• Decreases storage capacity
• Simplifies system layout
• …..
• Decreases chiller efficiency
• Decreases chiller capacity
Overall system efficiency ???
• Increases storage capacity
•……
• Does not allow chiller shut down!

7. District heating and cooling systems
Require expertise in
Plumbing
Pumps
Control

8. Plumbing - System Curves
A+B A B
A+B A B V A B V A B
Parallel
Serial

10. System balancing AHU1 AHU2 HC1 HC2 100 ft 1000 ft 10 gpm 2 gpm 10 ft
pump
BOILER

11. Pumps Raise pressure and produce flow Main type Centrifugal Example of
Turbine pump
Base mounted
Reading (textbook)
Page
Inline
engineering.com/downloads/cooltools/EDR_De signGuidelines_CoolToolsChilledWater.pdf

12. Curve for Multiple Pumps

13. Changing Pump Speed

14. Primary/Secondary and Tertiary Pumping
Reading Assignment:
Taylor, S., P. Dupont, B. Jones, T. Hartman and M. Hydeman Chilled water plant design guide. San Francisco: Pacific Gas & Electric Company.
engineering.com/downloads/cooltools/EDR_DesignGuidelines_C oolToolsChilledWater.pdf

15. Hydronic systems for district cooling/heating and buildings
Constant-Flow System, Single Chiller, Single Coil
Constant-Flow System, Single Chiller, Multiple Coils
Mixing valve that control
by-pass flow
Major pumping force
is the chiller pump

16. Control of coil temperature
Mixing valve that control the flow through the coil
Flow Variation as a Function of Valve Position
Same pressure
drop like a cooling coil
Major pumping force
is the chiller pump

17. Multiple chiller (or boilers)
Parallel
Serial

18. Primary-Loop Only Variable Speed Flow
Single chiller
Multiple chillers

19. Primary and Secondary Loop Variable Flow Design
Parallel chillers
Serial chillers

20. Large Plant or Building Distribution Systems
Primary/Secondary Loops with Variable Flow and Distributed Pumping

21. Primary/Secondary and Tertiary Pumping

22. Primary Pump Arrangements
Dedicate a pump for each chiller
Provide a common header for the pumps

23. Coil Pumping Strategies
Variable speed pumps vs. Single pas Valve vs. Mixing valves vs. Diverting Valves

24. Impact of plumbing on a cooling coil

25. Plumbing Arrangement in Building’s hydronic systems
Radiators
Baseboard heaters
Fan coil systems

26. Valves Section 5-14 and 6-15 in the textbook Types Butterfly Valves
Ball Valves
Globe Valves
Three way valves

27. Valve Sizing and Flow Coefficient
Cv value:
in liter/hour or….
in Pa
Control Valve Selection For Hydronic Systems
reference:

28. Control Valve Selection For Hydronic Systems
Before DC we tried to do this
Valve authority