APPENDIX I. FURNACE FAN CURVES TABLE OF CONTENTS 1.1 Furnace Fan Curves .............................................. I-1 LIST OF TABLES Table I.1 Coefficients for CFM equation for PSC motors ........................ I-1 Table 1.2 Coefficients for CFM equation for Two-Stage and Continuous Modulating

furnaces with ECM motors ........................................ 1-4

LIST OF FIGURES Figure I.1 Example Fit of CFM for 3-ton Non-Condensing Single-Stage Furnace ...... 1-2 Figure 1.2 Fan Curves for Non-Condensing Single-Stage Virtual Model Furnaces ..... 1-3 Figure 1.3 Fan Curves for Condensing Single-Stage Virtual Model Furnaces .......... 1-3 Figure 1.4 Fan Curves for Non-Condensing Two-Stage Virtual Model Furnaces

- High Fire ..................................................... 1-6 Figure 1.5 Fan Curves for Non-Condensing Two-Stage Virtual Model Furnaces

- Low Fire ..................................................... 1-6 Figure 1.6 Fan Curves for Condensing Two-Stage Virtual Model Furnaces

- High Fire ..................................................... 1-7 Figure 1.7 Fan Curves for Condensing Two-Stage Virtual Model Furnaces

- Low Fire ..................................................... 1-7 1.1 Table 1.1 Table 1.2 Figure 1.1 Figure 1.2 Figure 1.3 Figure 1.4 Figure 1.5 Figure 1.6 Figure 1.7 

### APPENDIX I. FURNACE FAN CURVES TABLE OF CONTENTS Furnace Fan Curves .......... . ................................... I-I 

### LIST OF TABLES Coefficients for CFM equation for PSC motors . .. .. . ... . .............. I-I Coefficients for CFM equation for Two-Stage and Continuous Modulating furnaces with ECM motors ........ . .............. . .. . ............. 1-4 

### LIST OF FIGURES Example Fit ofCFM for 3-ton Non-Condensing Single-Stage Furnace ...... 1-2 Fan Curves for Non-Condensing Single-Stage Virtual Model Furnaces .. .. . 1-3 Fan Curves for Condensing Single-Stage Virtual Model Furnaces .. ... ..... 1- 3 Fan Curves for Non-Condensing Two-Stage Virtual Model Furnaces

- High Fire . . . ................................... . ...... . ....... 1-6 Fan Curves for Non-Condensing Two-Stage Virtual Model Furnaces

- Low Fire ..................................................... 1-6 Fan Curves for Condensing Two-Stage Virtual Model Furnaces

- High Fire ............ .. ... ... ............... . ... . ............. 1-7 Fan Curves for Condensing Two-Stage Virtual Model Furnaces

- Low Fire .............. ... .. . . .. . .............. . ...... . . ... .. . 1-7

I-iAPPENDIX I. FURNACE FAN CURVES

1.1 Furnace Fan Curves Depending on the resistance (measured as static pressure ) of the supply and return air ducts, a furnace will move more or less air. When these airflow values are plotted graphically against pressure , they are referred to as fan curves. The Department developed fan curves for the single-stage virtual furnace models by fitting the manufacturer airflow and pressure data points from the basic model furnaces',', 3, 4, 5, 6, 7 to a fourth-order polynomial. The Department did this separately for each of the four nominal air handlers sizes for both non-condensing and condensing furnaces. The CFM for PSC blower motors is given by the following equation:



### CFM= mo+m'x(P)+m2x(P2)+m3X(P3)+ m4X(P4) Eq.I where, CFM

m0,1,2, 3,and4 P airflow in CFM reported by manufacturer,

coefficients derived from 4t' degree polynomial approximation (see Table I.1 for actual coefficient values), and external static pressure (in. w.g.). 'fable 1.1 Coefficients for CFM eq uation for PSC motors MO m, m2 m3 m4 2-ton 891.0 -590.8 564.6 -552.2 0.0 3-ton 1280.6 -279.8 194.4 -456.3 0 0 . 4-ton 1585.1 32.8 -575.7 -78.4 12.3 5-ton 1998.1 260.9 -93.2 -359.8 115.9 2-ton 840.4 70.0 -908.4 294.3 56.4 3-ton 1169.5 -226.1 -272 6 -95 7 137 0 . . . 4-ton 1541.2 -110.3 -777.3 419.0 0.0 5-ton 1915.1 -198.0 -594.5 -277.8 8.3 Figure 1.1 shows an example of a CFM curve for a 3-ton Non-Condensing Single-Stage Furnace fitted with the manufacturers' raw data.

I-1 

### APPENDIX I. FURNACE FAN CURVES 

### 1.1 Furnace Fan Curves Depending on the resistance (measured as static pressure) ofthe supply and return air ducts, a furnace will move more or less air. When these airflow values are plotted graphically against pressure, they are referred to as fan curves. The Department developed fan curves for the single-stage virtual furnace models by fitting the manufacturer airflow and pressure data points from the basic model furnaces l , 2,3 , 4,5,6 , 7 

### to a fourth-order polynomial. The Department did this separately for each of the four nominal air handlers sizes for both non-condensing and condensing furnaces. The CFM for PSC blower motors is given by the following equation: where, CFM 

### m O ,!,2, 3, and4 p 

### airflow in CFM reported by manufacturer, coefficients derived from 4 th 

### degree polynomial approximation (see Table 1.1 for actual coefficient values), and external static pressure (in. w.g.). 

### T bi 11

a e 

# . C ffi· t**~** 

### CFM oe IClen s or f**~** 

### PSC equa Ion or t 

### mo ors mo mI m2 m3 m 4 ell 2-ton 891.0 -590,8 564 . 6 -552 .2 0 . 0 .S til 

## = 3-ton 1280 . 6 -279.8 194.4 -456 . 3 0.0 Q,) '0 

## = = 4-ton 158 5 .1 32.8 -575.7 -78.4 12.3 U I 

## = 5-ton 1998.l 260.9 -93 . 2 -359.8 115.9 

## = Z ell 2-ton 840.4 70 . 0 -908.4 294 . 3 56.4 .S 3-ton 1169 . 5 -226.1 -272 . 6 -95 . 7 137 . 0 til 

## = Q,) '0 4-ton 1541.2 -110.3 -777.3 419.0 0 . 0 

## = = U 5-ton 1915.1 -198 . 0 -594.5 -277 . 8 8 . 3 

### Figure I.1 

### shows an example of a CFM curve for a 3-ton Non-Condensing Single-Stage Furnace fitted with the manufacturers' raw data.

I-I2500
2 000

• 1 500 n -- ♦ U ---._..--

®

00 Yak

00
0 0.00 0.10 0.20 Figure 1.1 0.30 0.40 0.50 0.60 Pressure ( in.w.g.) 0.70 0.80 0.90 1.00 M1GH MG M1 MB

P4UA i A Utiti+:!lVIaH

Example Fit of CFM for 3-ton Non-Condensing Single-Stage Furnace Figures 1.2 and 1.3 show the fan curves for non-condensing and condensing furnaces. Appendix H, Determination of Basic Furnace and Boiler Models, contains the data on the basic models that were used to develop these fan curves. 2500,--------------- - --------------,
2000**1- ------** **~- ~.** **----** ... -

_ 1500 -- :IE 

### ... !:!.**~** ii: 

### '" 

## • • '" a 1--- ---- -- - -- l 

### •
:;;: 1000**T-- -""---""** **-- "--** **--**
500 1- -----**--- ---** **----. --** **--~.-- --** **O~-~--~ ~--~-~-~-** **-~ -~--~-~** 

0.0 0 0 . 10 

### Figure 1.1 0.20 0.30 0.40 0.50 0 . 60 0.70 0.80 0 .90 1 .00 Pressure (In.w . g . ) 

### Example Fit of CFM for 3-ton Non-Condensing Single-Stage Furnace Figures 1.2 and 1.3 show the fan curves for non-condensing and condensing furnaces. Appendix H, Determination of Basic Furnace and Boiler Models, contains the data on the basic models that were used to develop these fan curves.

1-22500 -0,-2000 CFM -1600 CFM x-1200 CFM 2000 -800 CFM 9 1500 U. 0 9 0 t 1000 Q 0.- O 0 _IC 500 0 -+ - 0.00 0.25 0.50 0.75 External Static Pressure (in. w.g.) 1.00 Figure 1.2 Fan Curves for Non -Condensing Single-Stage Virtual Model

Furnaces

Figure 1.3 Fan Curves for Condensing Single-Stage Virtual Model Furnaces
I-3**~** IL**~**

### ~ IE 

# « 2500 ,--------- -- ,----- -- -----,------ -- ---,-- -- -------, 2000 o--o.iiii7"'=-;::::-= 1500 1000 500 .. _-- -**-~ --** **-- +-I** **~2000CFM ~1600CFM** **~1200CFM 0+-----------~----------** **_+-- --------_4~--------~**  0.00 0.25 0 . 50 0.75 1.00 External Static Pressure (in. w.g.) 

### Figure 1.2 Fan Curves for Non-Condensing Single-Stage Virtual Model Furnaces**~** IL**~** 

### := 0 IE 

# «**2500~-- --** **---- -r** **--------~~------~ ~====** **==~~** 2000 1500 1000 500**~2000CFM ~1600CFM** **~1200CFM** (**~** tr-Oo-c:I-o(-"")"',,-, ....SOO CFM 

### '-'**~(-o-.o. ~.** 



# -**'-'-~~**

J'.



# - - - ....... 

## ----I**0+-----------~-----------+ --** **--------_1----------~** 0.00 0.25 0 . 50 0.75 1.00 External Static Pressure (in. w.g.) 

### FigureI.3 Fan Curves for Condensing Single-Stage Virtual Model Furnaces 1-3The two-stage and continuous modulating design options in this analysis use brushless

permanent magnet motors (or sometimes referred as Electronically Commutated Motors (ECM)). Unlike PSC motors, these motors are electronically commutated and the speed they operate at can be varied across a wide range. These motors are controlled to operate the blower fans at a wide variety of air flows and static pressures. In the furnaces with these motors currently on the market, the controls are designed to provide a nearly constant air flow across the entire range of pressures at which they operate. Because of the versatility of the motors, manufacturers only offer furnaces with blowers nominally designed for operation with five-ton and three-ton air conditioners. The manufacturers provide control options to decrease the airflow for installations that use smaller air conditioners. To develop fan curves for furnaces with ECM motors, the Department fit quadratic curves through the air flow and pressure data points reported by manufacturers.8°9, 10, 11, 12, 13, 14 DOE did this separately for high-fire and low-fire operation for both non-condensing and condensing furnaces. See Figures 1.4 through 1.7 for charts showing the fit lines. Table 1.2 shows the coefficients for two-stage and continuous modulating furnaces with ECM motors using Eq. 2. Data from the basic models that were used to develop these fan curves is shown in Appendix H, Determination of Basic Furnace and Boiler Models.



### CFM = mo + m1 x (P) + m2 x (P2) Eq. 2 where, CFM = airflow in CFM reported by manufacturer, mo,1, anal = coefficients derived from 2°d degree polynomial approximation (see

Table 1.2 for actual coefficient values), and P = external static pressure ( in. w.g.). The two-stage and continuous modulating design options in this analysis use brushless permanent magnet motors (or sometimes referred as Electronically Commutated Motors (ECM)). Unlike PSC motors, these motors are electronically commutated and the speed they operate at can be varied across a wide range. These motors are controlled to operate the blower fans at a wide variety of air flows and static pressures. In the furnaces with these motors currently on the market, the controls are designed to provide a nearly constant air flow across the entire range of pressures at which they operate. Because of the versatility of the motors, manufacturers only offer furnaces with blowers nominally designed for operation with five-ton and three-ton air conditioners. The manufacturers provide control options to decrease the airflow for installations that use smaller air conditioners. To develop fan curves for furnaces with ECM motors, the Department fit quadratic curves through the air flow and pressure data points reported by manufacturers. 8 , 9, 10 , II, 12 , 13, 14 DOE did this separately for high-fire and low-fire operation for both non-condensing and condensing furnaces. See Figures 1.4 through 1.7 for charts showing the fit lines. Table 1.2 shows the coefficients for two-stage and continuous modulating furnaces with ECM motors using Eq. 2. Data from the basic models that were used to develop these fan curves is shown in Appendix H, Determination of Basic Furnace and Boiler Models. where, 

### CFM 

### m O ,], and 2 p 

### Eq.2
airflow in CFM reported by manufacturer, 

## = coefficients derived from 2nd degree polynomial approximation (see Table 1.2 for actual coefficient values), and = external static pressure (in. w.g.).

1-4Table 1.2 High Fire EL Low Fire

m0 m1 m1 m0 m' m2 2-ton 857.5 62.0 0.0 634.7 37.5 0.0 3-ton 1091.1 37.4 0.0 831.7 6.4 0.0 4-ton 1324.8 12.9 0.0 1028.7 -24.7 0.0 5-ton 1558.5 -11.7 0.0 1225.7 -55.8 0 0 . 2-ton 714.0 -16.4 -13.8 489.4 -50.2 0 0 . 3-ton 1003.0 -27.4 0.0 680.2 -31 5 0 0 . . 4-ton 1291.9 -38.4 13.8 870.9 -12.9 0.0 5-ton 1580.9 -49.5 27.6 1061.6 5.8 0.0 To be consistent with the analysis it did for the single-stage furnaces with PSC blower motors, the Department created virtual models for furnaces intended to act as air handlers for four and two ton air conditioners even though these are not currently offered by manufacturers. To generate the fan curves for the virtual furnaces intended to be used with 4 ton air conditioners, DOE calculated the average of the slopes and intercepts of the virtual furnaces with air handler for 5 ton and 3 ton air conditioners. This was done separately for high and low fire operations for non-condensing and condensing furnaces. For the virtual furnace models intended to operate with two-ton air conditioners, the fan curves were created by extrapolating the values for the slopes and intercepts of the virtual furnace models with air handlers intended to operate with three-ton and five- ton airconditioners. This was also done separately for high fire and low fire operation for both noncondensing and condensing furnaces. See Figures 1.4 through 1.7 for charts showing the fan curves for these air handlers.

Coefficients for CFM equation for Two-Stage and Continuous Modulating furnaces with ECM motors Table 1.2**~** 2-ton .S 

### '" 

# =**~** 3-ton 't:l 

# = Q 4 -ton 

### u I 

## = 5-ton Q Z**~** 2-ton .S 

### '" 3-ton 

# =**~** Coefficients for CFM equation for Two-Stage and Continuous Modulating furnaces with ECM motors High Fire Low Fire mo m J m 2 mo mJ m2 857.5 

# I 62.0 0 . 0 634.7 

# I 37.5 0.0 1091.1 37.4 0 .0 8 31.7 

# I 6.4 0 . 0 

# I 13 24 . 8 1 2. 9 0 . 0 102 8 .7 -24 .7 0 .0 1558 . 5 -11.7 0.0 1225.7 -55 . 8 

# I 0 . 0 714 . 0 

# I -16.4 

# I

- 13 .8 489.4 -50.2 0.0 1003 . 0 -27.4 0 .0 680.2 -31.5 0.0 

# I 

# I 

# I
't:l 4-ton 129l.9 -38.4 13.8 870.9 -12 . 9 

# I 0.0 

# I = Q - U 5-ton 

# I 1580 . 9 -49.5 27 . 6 1061.6 

# I 5 .8 

# I 0.0 

# I To be consistent with the analysis it did for the single-stage furnaces with PSC blower motors, the Department created virtual models for furnaces intended to act as air handlers for four and two ton air conditioners even though these are not currently offered by manufacturers. To generate the fan curves for the virtual furnaces intended to be used with 4 ton air conditioners, DOE calculated the average of the slopes and intercepts of the virtual furnaces with air handler for 5 ton and 3 ton air conditioners. This was done separately for high and low fire operations for non-condensing and condensing furnaces. For the virtual furnace models intended to operate with two-ton air conditioners, the fan curves were created by extrapolating the values for the slopes and intercepts of the virtual furnace models with air handlers intended to operate with three-ton and five- ton air conditioners. This was also done separately for high fire and low fire operation for both noncondensing and condensing furnaces. See Figures 1.4 through 1. 7 for charts showing the fan curves for these air handlers.

1-52500 -0-2000 CFM 11600 CFM 4-1200 CFM 2000 f 4-800 CFM g 1500 LL 0 1000
500 0 4 - 0.00 0.25 0.50 0.75 External Static Pressure (in. w.g.) 1.00 Figure 1.4

2500 Fan Curves for Non-Condensing Two-Stage Virtual Model Furnaces - High Fire

4-2000 CFM X1600 CFM 2000
9 1500 LL t)

500 04- 0.00 4-1200 CFM 4-800 CFM

0.25 0.50 0.75 External Static Pressure (in. w.g.) 1.00 Figure 1.5 Fan Curves for Non-Condensing Two-Stage Virtual Model

Furnaces - Low Fire I-6**~** II..**~ ~**  0 'E**~** 2500 2000 ----_ .. _ -- 1500


# - - 1000 . - - . - -- - 500



### o 0 .00 

# -**~**



# - -

---- - --
0 . 25

## ~OOCF" I -+-1600CFM**~1200CFM**
-- -

--- aoo CFM

......

--- - --- -- --- 1-- 

# -

- - ------ --
0 . 50 0 .75 External Static Pressure (in. w.g.) ..._"

...... ...... 

# -



# - - -

--
1 .00 

### Figure 1.4 Fan Curves for Non-Condensing Two-Stage Virtual Model Furnaces - High Fire 2500**~2000CF M**  -+-1600CFM 2000**~1200CFM**

___ aOOCFM**~** 1500 - - -- II..**~ ~**  0 'E**~** 1000 500 - -



### o 0.00 

### Figure 1.5**~ ~ ~** **-~** -""**~ ~** **~**
...... ...... 

# -

- 

# - - - 

# - - -

0.25 0 . 50 0.75 1.00 External Static Pressure (in. w.g.) 

### Fan Curves for Non-Condensing Two-Stage Virtual Model Furnaces - Low Fire 1-62500
2000 t9 1500 LL V --2000 CFM --1600 CFM -4-1200 CFM -M-800 CFM

1000
500

Figure 1.6

2500 04- 0.00 0.25 0.50 0.75 External Static Pressure (in. w.g.) 1.00 Fan Curves for Condensing Two-Stage Virtual Model Furnaces - High Fire

-0-2000 CFM --1600 CFM 2000
9 1500 U. U

500 --1200 CFM f800 CFM

0.00 0 0.25 0.50 0.75 External Static Pressure ( in. w.g.) 1.00 Figure 1.7 Fan Curves for Condensing Two-Stage Virtual Model Furnaces

- Low Fire I-7 

### i' u..**~ ~**  1: C( 2500 2000 1500 1000 500 _ .. 

### o 0.00 Figure 1.6



### i' u..**~ ~**  0 1: C( 2500 2000 1500 1000 500



### o 0.00 Figure 1.7**~2000CFM ~1600CFM**  -<>-1200 CFM . - .. . . ..

.....SOOCFM**~ ~** **~ ~** **~ ~** **~**



# - 

# - - 

# - 

# - ...



# - - - - 

# - 

# - --- 

# --- ---

0.25 0.50 0.75 1.00 External Static Pressure (in. w.g.) Fan Curves for Condensing Two-Stage Virtual Model Furnaces

- High Fire**~2000CFM ~1600CFM**  -<>-1200 CFM 1---.

.....SOOCFM**~ ~** 


# - - 

# - 

# -

. 

# -

- _ . 

# .- 

# - - - 

# - 

# - 

# -- --

0.25 0.50 0.75 1.00 External Static Pressure (in. w.g.) Fan Curves for Condensing Two-Stage Virtual Model Furnaces

- Low Fire 1-7REFERENCES

1. Lennox Industries Inc. Lennox Engineering Data: G40DF ( Merit Series Upflow/ Horizontal Gas Furnace ). 2003 . Lennox Industries , Inc. 2003.) <http://pirl.lennox.com/C03 e7ol4l/76EOZC21u /ehb_g4Odf 03 07.pdf> 2. Lennox Industries Inc. Lennox Engineering Data: G40UH ( Merit Series Upflow/ Horizontal Gas Furnace ). 2004 . Lennox Industries, Inc. <http ://pirl.lennox . com/C03e7o141 /76EOZC2lu/ehb

_g4Ouh

0407.pdf> 3. Lennox Industries Inc. Lennox Engineering Data.. G41 UF ( Merit Series Downflow Gas Furnace ). 2004 . Lennox Industries, Inc. <http ://pirl.lennox . com/C03e7ol4l /76EOZC21u/ehb_g4luf 0402.pdf> 4. Lennox Industries Inc. Lennox Engineering Data: G43 OF (Merit Series Upflow Gas Furnace). 2004. Lennox Industries, Inc. <http://pirl.lennox.com/C03e7ol4l/76EOZC21u/ehb_g43uf 0412.pdf> 5. Lennox Industries Inc. Lennox Engineering Data: G50DF (Elite Series Downflow Gas Furnace). 2003. Lennox Industries, Inc. <http://pirl.lennox.com/C03e7ol41/76EOZC21u/ehb_g5Odf 0307.pdf> 6. Lennox Industries Inc. Lennox Engineering Data: G50UH (Elite Series Upflow/Horizontal Gas Furnace). 2003. Lennox Industries, Inc. <http://pirl.lennox.com/C03e7o141/76EOZC2lu/ehb_g5Ouh-0307.pdf> 7. Lennox Industries Inc. Lennox Engineering Data: G51 MP ( Elite Series Multi-Position Gas Furnace). 2004 . Lennox Industries, Inc. <http ://pirl.lennox . com/C03e7ol4l/76EOZC2 lu/ehb-95 Imp

_0412.pdf> 8. Carrier Corporation . Carrier Product Data: 58CVA/CVX(Infinity 80 Series MultiPoise Furnace ). 2004 . Carrier Co. <http ://www.xpedio . carrier . com/idc/groups/public/documents /techlit/5 8cv - 3pd.pdf> 9. Carrier Co. Carrier Product Data: 58MVP (Infinity 96 Deluxe 4-Way Multipoise Furnace). 2004. Carrier Co. <http://www.xpedio. carrier . com/idc/groups /public/documents/techlit/5 8mvp-11 pd.pdf> 10. Lennox Industries Inc. Lennox Engineering Data: G61 WV (Multi-Position - Variable Speed Blower - Two-Stage Heat - Direct Vent/Non-Direct Vent). 2004. Lennox Industries, Inc. 11. Lennox Industries Inc. Lennox Engineering Data: G60UHV (Up-Flow/Horizontal - Two Stage Heat - Variable Speed Blower). 2003. Lennox Industries, Inc. 1-8 

### REFERENCES 1. Lennox Industries Inc. Lennox Engineering Data: G40DF (Merit Series Upjlow/Horizontal Gas Furnace). 

### 2003. Lennox Industries, Inc. 2003.) <http://pirl.lennox.comlC03e7014l176EOZC21u/ehb_g40dC0307.pdf> 2. Lennox Industries Inc. Lennox Engineering Data: G40UH (Merit Series Upjlow/Horizontal Gas Furnace). 

### 2004. Lennox Industries, Inc. <http://pirl.lennox.comlC03 

### e70 14117 6EOZC21 ul 

### ehb_g40uh _0407.pdf> 3. Lennox Industries Inc. Lennox Engineering Data: G41UF (Merit Series Downjlow Gas Furnace). 

### 2004. Lennox Industries, Inc. <http://pirl.lennox.comlC03e7014l176EOZC21u/ehb_g41uC0402.pdf> 

### 4. Lennox Industries Inc. Lennox Engineering Data: G43 UF (Merit Series Upjlow Gas Furnace). 

### 2004. Lennox Industries, Inc. <http://pirl.lennox.comlC03e7014l176EOZC21u/ehb_g43uC0412.p

### df> 5. Lennox Industries Inc. Lennox Engineering Data: G50DF (Elite Series Downjlow Gas Furnace). 

### 2003. Lennox Industries, Inc. <http://pirl.lennox.comlC03e7014l176EOZC21u1ehb_g50dC0307.pdf> 6. Lennox Industries Inc. Lennox Engineering Data: G50UH (Elite Series Upjlow/Horizontal Gas Furnace). 

### 2003. Lennox Industries, Inc. <http://pirl.lennox.comlC03e70141176EOZC21u1ehb_g50uh_0307.pdf> 

### 7. Lennox Industries Inc. Lennox Engineering Data: G51MP (Elite Series Multi-Position Gas Furnace). 

### 2004. Lennox Industries, Inc. <http://pirl.lennox.comlC03e7014l176EOZC21u/ehb_g51mp_0412. 

### pdf> 

## s. Carrier Corporation. Carrier Product Data: 58CVA/CVX(Injinity 80 Series MultiPoise Furnace}. 

### 2004. Carrier Co. <http://www.xpedio.carrier.comlidc/groups/publicl

### documents/techlitl5 Scv- 3pd.pdf> 9. Carrier Co. Carrier Product Data: 58MVP (Infinity 

### 96 Deluxe 4-Way Multipoise Furnace). 

### 2004. Carrier Co. <http://www.xpedio.carrier.comlidc/groups/publicl

### documents/techlitl5Smvp-l1 pd. pdf>

. 10. Lennox Industries Inc. Lennox Engineering Data: G61MPV (Multi-Position - Variable Speed Blower - Two-Stage Heat - Direct Vent/Non-Direct Vent). 

### 2004. Lennox Industries, Inc. 11. Lennox Industries Inc. Lennox Engineering Data: G60UHV (Up-Flow/Horizontal - Two Stage Heat - Variable Speed Blower). 

### 2003. Lennox Industries, Inc. 1-812. Lennox Industries Inc. Lennox Engineering Data: G60DFV (Down flow - Variable Speed Blower - Two-Stage Heat). 2004. Lennox Industries, Inc. 13. Trane Co. Trane Product Data: XV 80. 2004. Trane Co. 14. Trane Co. Trane Product Data: XV 90. 2004. Trane Co. 

### 12. Lennox Industries Inc. Lennox Engineering Data: G60DFV (Down-jlow - Variable Speed Blower - Two-Stage Heat). 

### 2004. Lennox Industries, Inc. 13. Trane Co. Trane Product Data: XV 80. 

### 2004. Trane Co. 14. Trane Co. Trane Product Data: XV 90. 

### 2004. Trane Co.

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