1. Optimized Designs October 20, 2016 Presented by Oscar Peraza
& Building Efficiency
The Large Tonnage Solutions Values are comprised of four major topics. Experience, sustainable solutions, innovation, and customer commitment.
The large tonnage solutions group is there for you, to meet the specific needs of your facility.
October 20, Presented by Oscar Peraza
Johnson Controls – Milwaukee, WI

2. Discussions Quick Review of Refrigerant Cycle for Chillers
The main components of a chilled water system & their relative size
How do chilled water and condenser water temperatures impact system efficiency?
When does it make sense to put a VSD on your chiller?
Real world example – 500 ton chiller. First Cost & Efficiency
Refrigerants – Latest Update 2

3. Basics: Refrigeration Cycle
Purpose of compressor:
raise pressure of the refrigerant vapor

4. Pressure Enthalpy Curve
BEST Program - YK Product Overview
Pressure Enthalpy Curve
Sub-Cooled
Liquid
Liquid-Vapor
Mixture
Superheated
Vapor
Pressure (Abs)
Saturated Liquid
Saturated Vapor
Enthalpy (BTU/lb)

5. Pressure Enthalpy Curve
BEST Program - YK Product Overview
Pressure Enthalpy Curve

6. Basics: Refrigeration Cycle
Evaporator Section P H

7. Basics: Refrigeration Cycle
Compressor Section P H

8. Basics: Refrigeration Cycle
Condenser Section P H

9. Basics: Refrigeration Cycle
Metering Device P H

10. Basics: Refrigeration Cycle
Refrigerant Cycle - Review

11. Centrifugal Chillers in today’s complex buildings How they work
BEST Program - YK Product Overview
Centrifugal Chillers in today’s complex buildings How they work
Prerotation Vanes
Impeller
Mist Eliminator
Diffuser Plate
Condenser
Flooded Evaporator
Subcooler
Orifice

12. Centrifugal Chillers in today’s complex buildings How they work
BEST Program - YK Product Overview
Centrifugal Chillers in today’s complex buildings How they work
Refrigerant rejects heat to atmosphere
Refrigerant absorbs heat from load
Pressure
Condenser
Lift (or Head Pressure)
Metering
Device
Compressor
CLICK FOR BLUE ARROWS TO APPEAR
Evaporator
Enthalpy

13. Basics: Refrigeration Cycle
Compressor Section P H

14. Centrifugal Chillers in today’s complex buildings How they work
BEST Program - YK Product Overview
Centrifugal Chillers in today’s complex buildings How they work
Pressure
95° F 35° C
Lift (or Head Pressure)
85° F 29° C
54° F 12° C
44° F 7° C
Enthalpy

15. Basics: Refrigeration Cycle Worksheet
Sub-Cooled Liquid
Liquid-Vapor Mixture
Superheated Vapor
Condenser
COND Saturated Temperature
Leaving COND Temperature
97F
Pressure (Abs)
95F
LIFT
Expansion
Compression
Leaving EVAP Temperature
44F
42F
Evaporator
EVAP Saturated Temperature
Saturated Liquid
Saturated Vapor
Enthalpy (BTU/lb)

16. Basics: Refrigeration Cycle Worksheet
Condenser Saturated Temp Condenser Leaving Water Temp Condenser Entering Water Temp Evaporator Entering Water Temp Evaporator Leaving Water Temp Evaporator Saturated Temp
97F
Approach
95F
85F
LIFT
54F
44F
42F

17. Basics: Refrigeration Cycle Worksheet
R-134a Chiller
Evaporator: LWT 44F / EWT 55F
Condenser: LWT 95F / EWT 85F
R-134a
Boils at -15.6F
@ 0 psig
118 psig
Condensation
COND Saturated Temperature
97F
Pressure (Abs)
95F
Leaving COND Temperature
81 psig
Expansion
Compression
Leaving EVAP Temperature
44F
42F
37 psig
Evaporation
EVAP Saturated Temperature
Enthalpy (BTU/lb)

18. Real World Energy Performance Capitalizing on Off-Design Conditions
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Real World Energy Performance Capitalizing on Off-Design Conditions
Lowering Condenser Water Temperature
Pressure
Condenser
Lift (or Head Pressure)
Compressor
Evaporator
Enthalpy

19. BEST Program - YK Product Overview
Real World Energy Performance How Does Leaving Chilled Water Temperature Affect Efficiency
Pressure
Condenser
Lift (or Head Pressure)
Compressor
Evaporator
Raising Chilled Water Temperature
Enthalpy

20. Real World Energy Performance Capitalizing on Off-Design Conditions
BEST Program - YK Product Overview
Real World Energy Performance Capitalizing on Off-Design Conditions
Reduces Energy Consumption
Pressure
Condenser
Lift (or Head Pressure)
Reduces Compressor Work
Compressor
Evaporator
Lowers the Lift
Raising Chilled Water Temperature
Enthalpy

21. Centrifugal Plants Chilled Water Temps & System Efficiency
Chilled Water Plant Components – 500 ton plant
Component
Chilled Water Pump ( ft wpd)
Condenser Water Pump ( ft wpd)
Cooling Tower Fan(s)
Centrifugal Chiller (500-ton) ??
Est. Break Horsepower
25.4 BHP
27.1 BHP
30 BHP
_____________
Total = 82.5 BHP
361 BHP
Chiller BHP = 4.4x all the other components combined

22. Centrifugal Plants Chilled Water Temps & System Efficiency
What is the best leaving chilled water temperature (lchwt) for system efficiency? 38 44 46
The warmest temperature capable of providing
your desired airside leaving air temp 42 40 45

23. Centrifugal Plants Chilled Water Temps & System Efficiency
Warmer leaving chilled water saves energy
AND you can still achieve the airside performance you need
Chilled Water Design Temp:
For every degree the leaving CHW adjusts, the chiller gains/losses about 2% - 2.5% in efficiency
On Centrifugal chillers, a higher delta T with the same leaving CHW temp does not impact energy efficiency.
“Outside” Temperatures drive chiller efficiency (Leaving Condenser – Leaving Chilled)
For example:
Energy consumption increases 5% using 42 deg CHW vs 44 deg CHW
There is a negligible difference utilizing 44/54 vs 44/60

24. Centrifugal Plants Chilled Water Temps & System Efficiency
Message :
With constant equipment cost, you will improve system efficiency with warmer CHW design
temps.
Example System Assumptions
500 Tons
Centrifugal Chiller
85/95 degree condenser water (3 gpm/ton)
ECHWT/LCHWT Efficiency (Kw/ton) Variance (% Efficiency)
42/ & NPLV
44/ & NPLV % / %
45/ & NPLV % / %
Delta T has little effect on chiller efficiency
ECHWT/LCHWT Efficiency (Kw/ton)
42/ & NPLV
44/ & IPLV
45/ & NPLV

25. What temperature chilled water do I need?
54 deg air is achievable w/ 45 deg Chilled Water Regardless of Entering Air Conditions
What temperature chilled water do I need?

26. Centrifugal Plants Chilled Water Temps & System Efficiency
Message:
Warmer chilled water temps do not significantly impact airside performance or cost
Example Airside Impact
80/67 Entering Mixed Air Temp for AHU cooling Coil
8,000 CFM 500 fpm
LAT = Sub 54 (54 db / 53.5 wb)
ECHWT/LCHWT LAT db / LAT wb Minimum Cooling Coil Required First Cost vs 42/56
42/ / rows 9 FPI
44/ / rows 9 FPI $239
45/ / rows FPI $283
44 deg option increases APD over 42 deg option by only 0.14”
45 deg option increases APD over 42 deg option by only 0.23”
Air Pressure Drop Difference
42 vs 45 CHW = 0.16” wpd

27. Yearly System Energy Savings
Assumptions: 500 ton chiller 3,000 yearly operating hours 350-ton average Load $0.10/kwh 13 AHUs 8k CFM (27-tons) = 350 ton average load Airside BHP based on AF 4.0” TSP vs 4.16” TSP (0.16” apd increase) Annual Chiller Energy Cost = (Avg Load)(Run Hours)(NPLV kw/ton)($/kwh) Annual Airside Energy Cost = (Qnty AHUs)(Run Hours)(BHP)(0.746 kw/bhp)($/kwh) Chiller: 42/56 design, kw/ton NPLV: Chiller: 45/59 design, kw/ton NPLV: Airside: 42/56 design, 7.70 BHP per 8k CFM AHU: Airside: 45/59 design, 7.92 BHP per 8k CFM AHU:
$38,115 / year
$34,125 / year $3,990 reduction/year on Chiller
$22,402 / year
$23,042 / year $640 extra/year on Airside
Net System Energy Savings = $3,350, ~ 5.5% per year

28. BEST Program - YK Product Overview
Real World Energy Performance Capitalizing on Lower Leaving Condenser Water Temperatures
Lowering Condenser Water Temperature
Pressure
Lowers the Lift
Condenser
Lift (or Head Pressure)
Compressor
Reduces Compressor Work
Evaporator
Reduces Energy Consumption
Enthalpy

29. Centrifugal Plants Condenser Water Temps & System Efficiency
Colder LEAVING condenser water reduces system energy consumption
Condenser Water Design Temp:
Entering CW temp has a minimal impact on efficiency.
Leaving CW temp drives chiller efficiency.
For every degree the leaving CW temp adjusts, the chiller gains/losses about 1.5% - 2% in efficiency
Example:
A chiller selected for 2 gpm/ton or 85/100 will take a 7.5% to 10% efficiency hit vs 3 gpm/ton

30. 21.7 BHP – System BHP reduction from 3 gpm/ton
Centrifugal Plants Chilled Water Temps & System Efficiency
Message :
With constant equipment cost, you will improve system efficiency with 3 gpm/ton
Example System Assumptions
500 Tons
Centrifugal Chiller
44/54 degree chilled water
ECWT & Flow Efficiency (Kw/ton) BHP Variance (% Efficiency)
85 & 1500 gpm & NPLV BHP
85 & 1000 gpm & NPLV BHP BHP (- 7.8% / %)
Condenser Water Pump Selection (60 ft WPD)
Flow BHP Variance
1500 gpm BHP
1000 gpm BHP BHP
21.7 BHP – System BHP reduction from 3 gpm/ton

31. What’s going on with our current refrigerants…
INTENT
To reiterate what we have covered in a clear message that the refrigerants that JCI utilizes are the best choices for today's market.
[Suggested Script]
To reiterate what we have covered and the primary take away from this training is that R134a and R410a do NOT have a phase out date. Johnson Controls utilizes these refrigerants, R134a and R410a, because they are efficient, safe, affordable, available and reliable. They are not subject to any bans and will be available for the life of the equipment.

32. Refrigerant regulations such as EPA SNAP and European F-gas target refrigerants for specific applications based on emissions SNAP – Significant New Alternatives Policy
(i.e. R410A)
(i.e. R134a, R1234yf)
(i.e. R123, R245fa)
Source: U.S. EPA

33. US EPA SNAP Change of Status (De-listing rule)
No changes to impact stationary air-conditioning.
Applicable to new equipment only.

34. What’s going on with our current refrigerants…
December 31, 2019: No new chillers with R-123 can be manufactured.
December 31, 2023: No new chillers with HFC’s can be manufactured, including R-134a and R-410a.
December 31, 2029: The end of production and importation of R-123.
See below for Phase-Down schedule of HFC. Phase down schedule does not target any individual HFC, but addresses them as a whole.
INTENT
To reiterate what we have covered in a clear message that the refrigerants that JCI utilizes are the best choices for today's market.
[Suggested Script]
To reiterate what we have covered and the primary take away from this training is that R134a and R410a do NOT have a phase out date. Johnson Controls utilizes these refrigerants, R134a and R410a, because they are efficient, safe, affordable, available and reliable. They are not subject to any bans and will be available for the life of the equipment.

36. Summary Warmer chilled water temps improve SYSTEM efficiency
Colder leaving condenser water temps improve SYSTEM efficiency
460 volt variable speed drives are no longer expensive
Variable Speed Drives save on energy with any reduction in lift
Variable Speed Drives save on energy with any reduction in load
Make sure you keep up with latest refrigerant regulations, but don’t be intimidated 36

37. BEST Program - YK Product Overview
Question Period

38. “We’re There!”
THANK YOU