1. Outside the
Box
Introduction to Quality Installation of
High Efficiency Heating and Cooling Systems

2. Overview
Outside the Box – Introduction to Quality
Installation of High Efficiency HVAC Systems
• Common Installation Issues Impacting Performance
• Pressure Measurement and Diagnostics
• Temperature Measurement and Diagnostics
• Equipment vs. System Performance
• Finding a Professional
• Conclusion - Next Steps

3. Common Installation Issues Impacting Performance
The House IS a System
DUCT SYSTEM
SHELL
TIGHTNESS
INSULATION
CONTROLS
VENTILATION
HEATING AND SYSTEM
A/C
COMBUSTION
APPLIANCES
© 2009 ESI, Inc.

4. Common Installation Issues Impacting Performance
HVAC Efficiency - It’s All About the Installation
1. Equipment Sizing / Selection – Manual J is the
ANSI standard for sizing residential equipment
2. Duct Design / Sizing – On average, duct systems
are grossly undersized and restrict airflow
significantly
3. Duct Leakage – Delivering air to its destination is
critical, but sealing ducts is often more complicated
than it might appear
4. Filter Type and Size – Improperly sized filters, or
filter types other than what the designer assumed
can wreak havoc on the system’s airflow
© 2009 ESI, Inc.

5. Common Installation Issues Impacting Performance
HVAC Efficiency - It’s All About the Installation
5. Equipment Setup – Equipment today is complex
and requires great attention to detail in its setup,
configuration, and control system(s)
6. Air Balancing – Ensuring the right amount of air is
delivered to each room improves comfort and can
help reduce utility costs
7. Combustion Efficiency – Maximizing the
delivered heat out of the fuel purchased requires
more than what is included in a typical “swap the
box” replacement
8. Multi-Speed / Staged Equipment – Advanced
technology means even more setup is required to
operate properly
© 2009 ESI, Inc.

6. Common Installation Issues Impacting Performance
How Do Contractors Size Equipment?
Survey Results (FSEC - 489 HVAC Contractors)
– Software Represents Manufacturer’s Software
– Other is primarily use of a “Short Form” or Utility Method

7. Common Installation Issues Impacting Performance
Central Iowa Sizing Results - Heating
© 2009 ESI, Inc.

8. Common Installation Issues Impacting Performance
Central Iowa Sizing Results - Cooling
Cooling Sizing to Load - TOTAL Summary (100 Home Sample)
3500000
3000000
2500000
2000000 Design Cooling
Btuh
Manual J Max Size
Installed (Output)
1500000
1000000
500000
0
© 2009 ESI, Inc.

9. Common Installation Issues Impacting Performance
STATE OF THE INDUSTRY
Nine out of ten HVAC systems cannot
operate properly or efficiently without
being repaired first.
© 2009 ESI, Inc.

10. Common Installation Issues Impacting Performance
Central Iowa Results – Installed Efficiency
Load
© 2009 ESI, Inc.

11. Common Installation Issues Impacting Performance
Central Iowa Results – Installed Efficiency
Load
© 2009 ESI, Inc.

12. Common Installation Issues Impacting Performance
The national average shows HVAC
systems deliver only 57% of the
equipment rated BTU into the building
© 2009 ESI, Inc.

13. Common Installation Issues Impacting Performance
Good news! After appropriate renovations, the
average HVAC system can deliver over 90% of
the equipment rated BTU into the building
6.2%
System BTU Loss of
equipment rated capacity
93.8%
System BTU Delivery of
equipment rated
capacity
SOURCE: NCI Certified Contractor Survey 11-05 to 2-06
© 2009 ESI, Inc.

14. Common Installation Issues Impacting Performance
Less than 3% of
service agreements
include the duct
system…
SO WHO’S
CHECKING IT?
© 2009 ESI, Inc.

15. Common Installation Issues Impacting Performance
How heavy is “standard” air?
Training room Length x Width x Height
Room cubic Feet x .075 pounds = the
weight (in lbs) of the air in this room
A typical fan has to move about 90
pounds of air per minute. That’s 5400
pounds per hour.
© 2009 ESI, Inc.

16. Common Installation Issues Impacting Performance
So, where do we start?
Evaluate the System, not just the Box…
Static Pressure – Helps us know if
the system is delivering the right
amount of air
System Temperatures – Helps us
understand the impact (gain / loss) of
the duct system
© 2009 ESI, Inc.

17. Pressure Measurement and Diagnostics
Static Pressure is
a lot like blood
pressure.
It’s the first,
quick test of an
HVAC system’s
“circulation.”
© 2009 ESI, Inc.

18. Pressure Measurement and Diagnostics
Static Pressure is the amount of
resistance the fan must overcome to
move air throughout the system
Pressure is measured
using a manometer
Like blood pressure,
static pressure that is
too high or too low can
cause problems!
Fewer than 6% of contractors even check static pressure!
© 2009 ESI, Inc.

19. Pressure Measurement and Diagnostics
Supply +.19”
+ Return -.31”
Equals .50”
Add
The most common static
pressure rating for
residential equipment is .50”
of Total External Static
Pressure
© 2009 ESI, Inc.

20. Pressure Measurement and Diagnostics
Total External Static Pressure Challenge
.50” rated fan
-.34” +.41”
What is the system return static pressure? -.34”
_______
What is the system supply static pressure? _______+.41”
.75”
What is the system total external static pressure? _______
What’s wrong with this system? Total Static Pressure
too high – airflow will
be low
© 2009 ESI, Inc.

21. Pressure Measurement and Diagnostics
© 2009 ESI, Inc.

22. Pressure Measurement and Diagnostics
A pressure
drop is the
difference
between two
readings…
We measure
pressure
drops to help
troubleshoot
airflow
restrictions
© 2009 ESI, Inc.

23. Pressure Measurement and Diagnostics
Pressure drop is
measured by
subtracting the
pressures on both
side of a system
component
© 2009 ESI, Inc.

24. Pressure Measurement and Diagnostics
Pressure Drops
1. FILTERS – Dirty filters or incorrectly-sized filters will
have a higher pressure drop
2. COILS – Dirty coils, or newer higher-efficiency coils
will have a higher pressure drop
3. DAMPERS – Dampers that are not operating properly
or are too restrictive will have a higher pressure drop
4. ACCESSORIES – Basically, anything that is added
into the air stream or is part of the duct system will
have a pressure drop associated with it
© 2009 ESI, Inc.

25. Pressure Measurement and Diagnostics
Coil Pressure Drops - Example
© 2009 ESI, Inc.

26. Pressure Measurement and Diagnostics
Filter Pressure Drops - Example
© 2009 ESI, Inc.

27. Pressure Measurement and Diagnostics
Top 10 Static Pressure Repairs
1. Filters are the number one cause of poor
Indoor Air Quality in this country today. If the
fan can’t move the air, the V in HVAC doesn’t
occur.
2. Clean cooling coils. Inspection alone does not
verify the coil is clean. Measure coil pressure
drop. Average 14 SEER coil drop = .32”
3. The duct sizes typically used across the US
are far too small. Adding an additional large
return duct to relieve high static pressure.
© 2009 ESI, Inc.

28. Pressure Measurement and Diagnostics
Top 10 Static Pressure Repairs
4. Poor duct installation is next. Straighten
ducts, improve duct suspension, lengthen the
radius of elbows, replace duct transition, the
list goes on and on.
5. Damaged ducting. Cable guys, phone repair
techs and alarm system installers have little
idea of their impact on duct system
performance.
© 2009 ESI, Inc.

29. Pressure Measurement and Diagnostics
Top 10 Static Pressure Repairs
6. Aging ducting. How long does flexible
ducting last in a 140 degree attic?
7. Duct systems designed for older, less
efficient systems. In most areas of the
country, ducts are significantly undersized.
8. Inadequate fan capacity. With today’s coils
and filter pressure drops, ask for a variable
speed or higher static pressure rated fan.
© 2009 ESI, Inc.

30. Pressure Measurement and Diagnostics
Top 10 Static Pressure Repairs
9. Outdated, rule-of-thumb duct design
methods.
10. Restrictive registers and grilles.
Consider replacing with good quality
commercial grilles.
© 2009 ESI, Inc.

31. Temperature Measurement and Diagnostics
Measuring Temperature Change
∆t = Delta t (The difference between
two related temperatures)
When measuring equipment ∆t is the difference between
the temperature entering and exiting the equipment.
When measuring system ∆t is the difference between the
temperature entering and exiting the system – or average
return grille temperature minus average supply register
temperature.
© 2009 ESI, Inc.

32. Temperature Measurement and Diagnostics
Equipment ∆t
For Cooling
Entering Temperature
-Exiting Temperature
Equals Equipment ∆t
For Heating
Exiting 120°
Entering - 70°
Equipment ∆t 50°
© 2009 ESI, Inc.

33. Temperature Measurement and Diagnostics
System ∆t
For Cooling
Supply Register Temperature
-Return Grille Temperature
Equals System ∆t
For Heating
Return Grille 75°
Supply Register - 115°
System ∆t only 40°
© 2009 ESI, Inc.

34. Temperature Measurement & Diagnostics
Percent of System BTU Duct Loss or Gain
Let’s take a look at system performance.
This quick test and calculation offers a snapshot of system
performance by taking only four temperature
measurements and working a short formula.
Gather the following four temperature measurements.
1. The temperature entering the equipment
2. The temperature exiting the equipment
3. A typical supply register air temperature
4. A typical return grille air temperature
Page 119

35. Temperature Measurement & Diagnostics
Percent of System BTU Duct Loss or Gain
Next, subtract to find the equipment delta t, and subtract to find
the system delta t. The divide as shown in the formula below.
System Loss or Gain Formula
Duct System Temperature Loss
System Loss % =
Equipment Temperature Change
Page 119

36. Percent of System BTU Duct Loss or Gain
Cooling Example:
Temperature Diagnostics and Repairs
Duct System Temperature Gain = 9°
= 50% System Gain
Equipment Temperature Change = 18°
Heating Example:
Duct System Temperature Loss = 15°
= 25% System Loss
Equipment Temperature Change = 60°
Page 119

37. Duct Loss Example (Sensible BTUs)
72°
67°
Temperature Measurement & Diagnostics
Heating Mode
Equipment ΔT 50°
System ΔT 30°
Return Duct Loss 5°
Supply Duct Loss 15°
What would the supply
register temp be if there
was no duct loss? 117° 102°
122º
Page 120

38. Duct Loss Example (Sensible BTU)
Temperature Measurement & Diagnostics
Heating Mode – Use Data from Previous Drawing
Return Grille Temp = 72° Supply Reg Temp = 102°
Return Plenum Temp = 67° Supply Plenum Temp = 117°
Return Duct Loss = 5° Supply Duct Loss = 15°
Return Duct Loss + Supply Duct Loss = Total Duct Loss
5° + 15° = 20°
Total Duct Loss / Equipment ΔT = % Duct Temp Loss
20° / 50° = 40%
Page 121

39. Temperature Measurement & Diagnostics
Duct Loss Challenge (Sensible BTU)
73°
69°
Heating Mode
Equipment ΔT 50 °
System ΔT 29 °
Return Duct Loss 4 °
Supply Duct Loss 17 °
What would the
supply register
temp be if there
was no duct loss? 119° 102°
____
123º
Page 122

40. Duct Loss Example (Sensible BTU)
Temperature Measurement & Diagnostics
Heating Mode – Use Data from Previous Drawing
Return Grille Temp = 73° Supply Reg Temp = 102°
Return Plenum Temp = 69° Supply Plenum Temp = 119°
Return Duct Loss = 4º Supply Duct Loss = 17°
Return Duct Loss + Supply Duct Loss = Total Duct Loss
17° + 4° = 21°
Total Duct Loss / Equipment ΔT = % Duct Temp Loss
21° / 50° = 42%
Page 123

41. Temperature Measurement & Diagnostics
Duct Loss Challenge (Sensible and Total BTU)
76° DB 70° DB
63.8° WB 62.4° WB
Cooling Mode
ΔT ΔH
Equipment ° ____
System ° ____
Ret. Duct Loss ° ____
Sup. Duct Loss ° ____
60° DB 66° DB
56.2° WB 58.1° WB
Page 125

42. Temperature Measurement & Diagnostics
Duct Loss Challenge (Sensible and Total BTU)
76° DB 70° DB
63.8° WB 62.4° WB
Cooling Mode
ΔT
Equipment 16 °
System 4°
Ret. Duct Loss 6°
Sup. Duct Loss 6 °
60° DB 66° DB
56.2° WB 58.1° WB
Page 125

43. Duct Loss Example (Sensible BTU)
Temperature Measurement & Diagnostics
Cooling Mode – Use Data from Previous Drawing
Return Grille Temp = 70° Supply Reg Temp = 66°
Return Plenum Temp = 76° Supply Plenum Temp = 60°
Return Duct Loss = 6º Supply Duct Loss = 6°
Return Duct Loss + Supply Duct Loss = Total Duct Loss
6° + 6° = 12°
Total Duct Loss / Equipment ΔT = % Duct Temp Loss
12° / 16° = 75%
Page 126

44. Temperature Measurement and Diagnostics
Duct Location
• Inside Conditioned Space is Preferred
• Attic/Crawl Space locations require
significant duct insulation strategies
• Sometimes ducts that seem like they are
“inside” are really more connected to outside
• Ducts in an unfinished basement often
require duct insulation
© 2009 ESI, Inc.

45. Temperature Measurement and Diagnostics
Duct Sealing
Leaky Ductwork Costs U.S. Consumers an
Average of $5,000,000,000 per Year
– Leaky Ducts Can Cause Enormous Performance
Penalties
– Leaky Ducts Inside the Envelope are Important
Too - Sometimes You Only Think They’re Inside
– Comfort Can be Extremely Difficult to Achieve
With Leaky Ducts
– Leaky Returns Can Introduce Dirt, Dust,
Insulation Fibers, etc Into the System
© 2009 ESI, Inc.

46. Temperature Measurement and Diagnostics
Duct Sealing
Types of Sealants
– Duct Mastic - Can be Used Easily on New Home
Ducts or Accessible Existing Home Ducts
– Aerosol Sealants - Seal Ducts from Inside Out
– Foil Tape - Difficult to Install Properly, and Falls
Off Over Time
– Silicone - Expansion / Contraction Tends to
Break Down Seals Over Time
© 2009 ESI, Inc.

47. Temperature Measurement and Diagnostics
Duct Sealing - DANGER
Sealing Ducts May Not Always Help Solve
Problems…
If the Ducts are Already Too Small,
What Happens When You Seal Them?
Before Sealing, You Need to Be Sure That
the System Can Afford It!
© 2009 ESI, Inc.

48. Temperature Measurement and Diagnostics
System Temperature Defects
DEFECT REPAIR
More than 3 Add additional duct insulation or
degrees of thermal relocate ducts into conditioned
loss through the space
duct system
Duct airflow loss Repair or replace ducts. Tighten
joints, seal ducts
Temperature Seal joint between boot and
change at grille register to stop infiltration from
unconditioned area.
© 2009 ESI, Inc.

49. Temperature Measurement and Diagnostics
System Temperature Defects
DEFECT REPAIR
More than 3° Repair duct system. Test,
difference between adjust, and balance the HVAC
room temperatures system
Damaged or Repair or replace equipment
inadequate equipment AND duct system. Do not just
or accessories “swap boxes”
© 2009 ESI, Inc.

50. Equipment Performance vs. System Performance
Component vs. System Testing
Traditional Service and Installation Practices
Require Component-Level Testing Only
• Component-Level Testing = “Perfect World” Testing
*Perfect-World Testing Merely Makes a Statement
About Potential Efficiency
• System-Level Testing = “Real World” Testing
*Real-Word Testing Measures the Actual,
Installed Efficiency
© 2009 ESI, Inc.

51. Equipment Performance vs. System Performance
BENEFITS OF ADDRESSNG THE SYSTEM
1. Equipment Change Only: BTU PER THERM 54,720
2. Equipment & Renovation: BTU PER THERM 86,400
3. Renovation Only: BTU PER THERM 72,000
© 2009 ESI, Inc.

52. Equipment Performance vs. System Performance
GETTING THE BEST VALUE
Quality Installation is critical to maximizing Installed
Efficiency!
Replacement with high efficiency equipment typically has
little impact on utility consumption. In fact, sometimes
customers have reported an increase in natural gas
consumption.
The primary reason for this is that newer furnaces require
50% more airflow than older furnaces and duct systems
are typically significantly undersized. Without considering
the entire system, the great new equipment may not
even have a chance to work properly!
© 2009 ESI, Inc.

53. Equipment Performance vs. System Performance
The Tale of Two Systems
100k BTU Output Furnace Replacement
Current Annual Heating Cost = $1353 (60% Installed Eff.)
• Replace Unit Only w/ 95% AFUE • Replace Unit + Duct Renovation
• Installed Eff. Decreased to 57% • Installed Eff. Increased to 89%
• Reduced Heating Bill by $173/yr • Reduced Heating Bill by $597/yr
• $5,000 Cost • $7,000 Cost
• $1,500 Tax Credit • $1,500 Tax Credit
• $450 Utility Incentive • $450 Utility Incentive
• Total Investment = $3,050 • Total Investment = $5,050
• Payback = 17.6 years • Payback = 8.5 years
• Est. Equipment Life = 15 years • Est. Equipment Life = 15 years
• ROI over Life of Equip. = $2,595 • ROI over Life of Equip. = $8,955
• Residual Return After Payback = • Residual Return After Payback =
($455) $3,905
© 2009 ESI, Inc.

54. Conclusion - Next Steps
Finding a Professional
-ASK QUESTIONS!
-How do you size equipment?
-How will you design/re-design my duct system?
-Do you check static pressure?
-How will you maximize my SYSTEM’S efficiency?
-Work with an Energy Rater with HVAC expertise
-Focus your efforts “Outside the Box” as well
-Accept that the House is a System
© 2009 ESI, Inc.

55. Conclusion - Next Steps
Thank You for Attending
Today’s Session!
Questions?