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Page 20

Table 8. Merit

®

 CBX25UHV‐048 Air Handler Performance (0 through 0.80 in. w.g. [0 — 200 Pa] External Static Pressure Range)

“ADJUST”

Jumper

Setting

Jumper Speed Positions

“HEAT” Speed

First-Stage “COOL” Speed

Second-Stage “COOL” Speed

1

2

3

4

1

2

3

4

1

2

3

4

cfm

cfm

cfm

cfm

cfm

cfm

cfm

cfm

cfm

cfm

cfm

cfm

+

1450

1670

1880

2340

1050

1200

1340

1650

1440

1670

1950

2340

NORM

1340

1520

1730

2100

950

1100

1230

1520

1325

1530

1740

2150

1210

1390

1570

1915

850

1000

1110

1375

1200

1380

1600

1950

NOTES ­ 
The effect of static pressure, filter and electric heater resistance is included in the air volumes listed.
First-stage cooling air volume is 70% of COOL (second-stage) speed setting. Continuous blower speed is approximately 50% of COOL speed setting.
Lennox Harmony III™ Zoning System applications ­ minimum blower speed is 450 cfm.

Table 9. Merit

®

 CBX25UHV‐060 Air Handler Performance (0 through 0.80 in. w.g. [0 — 200 Pa] External Static Pressure Range)

“ADJUST”

Jumper

Setting

Jumper Speed Positions

“HEAT” Speed

First-Stage “COOL” Speed

Second-Stage “COOL” Speed

1

2

3

4

1

2

3

4

1

2

3

4

cfm

cfm

cfm

cfm

cfm

cfm

cfm

cfm

cfm

cfm

cfm

cfm

+

1700

1930

2120

2275

1225

1410

1530

1690

1720

1930

2140

2270

NORM

1570

1760

1925

2100

1120

1260

1400

1540

1580

1765

1970

2100

1420

1595

1760

1920

1015

1160

1275

1390

1430

1625

1780

1890

NOTES ­ 
The effect of static pressure, filter and electric heater resistance is included in the air volumes listed.
First-stage cooling air volume is 70% of COOL (second-stage) speed setting. Continuous blower speed is approximately 50% of COOL speed setting.
Lennox Harmony III™ Zoning System applications ­ minimum blower speed is 450 cfm.

Table 10. Merit

®

 CBX25UHV,  Thermostat and Single-Stage Outdoor Unit Operating Sequence

Operating Sequence

System Demand

System Response

System
Condition

Step

Thermostat Demand

Relative Humidity

Com­

pressor

Air

Handler

CFM

(COOL)

Comments

Y1

Y2

O

G

W1

W2

Status

D

NO CALL FOR DEHUMIDIFICATION

Normal Operation

1

On

On

On

Acceptable

24 VAC

High

100%

Compressor and indoor air handler fol­
low thermostat demand

BASIC MODE (only active on a Y1 thermostat demand)

Normal 
Operation

1

On

On

On

Acceptable

24 VAC

High

100%

Thermostat energizes Y1 and de-ener­
gizes D on a call for dehumidification

Dehumidification Call

2

On

On

On

Demand

0 VAC

High

60%/65

70%*

PRECISION MODE (operates independent of a Y1 thermostat demand)

Normal Operation

1

On

On

On

Acceptable

24 VAC

High

100%

Dehumidification mode begins when hu­
midity is greater than set point

Dehumidification Call

2

On

On

On

Demand

0 VAC

High

60%/65%

70%*

Dehumidification Call
ONLY

1

On

On

On

Demand

0 VAC

High

60%/65%

70%*

Thermostat will try to maintain room hu­
midity setpoint by allowing the room
space to maintain a cooler room ther­
mostat setpoint**

Jumpers at indoor unit with a single stage outdoor unit
With Condensing unit - Y1 to Y2 and R to O
With Heat Pump - Y1 to Y2

* During dehumidification, cooling air handler speed is as follows: 70% of COOL cfm for 018, 024, 030; 65% for 036; 60% for 042, 048 and 060 units.
** Thermostat will maintain the room temperature up to 2°F (1.2°C) cooler than the room thermostat setting in precision mode.

Содержание CBX25UHV-018

Страница 1: ...507616 02 7 2018 Shipping and Packing List Package 1 of 1 contains the following 1 Assembled air handler unit factory equipped for up flow or horizontal air discharge application includes up flow and horizontal drain pans and pre installed air filter Check equipment for shipping damage If found immediately report damage to the last carrier Check the unit rating plate to confirm that delivered unit...

Страница 2: ...s Up flow inches mm NOTE Unit is shipped configured for horizontal left hand air discharge Unit may be converted to horizontal right hand air discharge by repositioning horizontal drain pan Dimensions remain the same in all configurations ...

Страница 3: ...ning Systems latest edition The air handler is shipped from the factory completely assembled This unit is provided with flanges for connecting the supply plenum Do not remove the cabinet knockouts until it has been determined which knockouts will need to be removed for the installation Select the air discharge position which best suits the site conditions Consider required clearances space routing...

Страница 4: ... in the desired location and properly slope the unit see page 8 Connect the return and supply air plenums as required using sheet metal screws 4 In applications that do not include a return air plenum install units on a stand that is raised at least 14 above the floor This ensures proper air return HORIZONTAL DRAIN PAN IMPORTANT REMOVE PAN FOR BEST EFFICIENCY AND AIR FLOW UP FLOW DRAIN PAN UP FLOW...

Страница 5: ...ge the following field modifications are required 1 Remove and set aside blower and coil access panels 2 Remove brackets securing pans to unit See figure 4 Figure 4 Remove Main Drain Pan Mounting Brackets 3 Remove coil assembly bottom drain pan and horizontal drain pan as one unit from the air handler Figure 5 Remove Coil Assembly Bottom Drain Pan and Horizontal Drain Pan As A Unit 4 Remove the bl...

Страница 6: ...that Hold the Coil and Horizontal Drain Pan in Place Repositioning Black Box on Motor Module 018 024 and 030 Units When the horizontal drain pan is moved to the right side of the air handler the black box on the back of the supply fan motor will prevent the insertion of the blower assembly back into the cabinet The black box must be repositioned to overcome this issue Tools and Material Required 1...

Страница 7: ...r than the original position Figure 12 Black Box Repositioned on Motor Module 11 Slide the blower assembly into the cabinet to confirm clearance between the horizontal drain pan and the black box Remove the blower assembly and relocate the black box if necessary to achieve clearance Make note of the new position Apply two new strips of double sided tape to the black box and affix it to the module ...

Страница 8: ...ater standing in the pan THIS CORNER SHOULD BE 5 8 1 8 HIGHER THAN DRAIN CORNER DRAIN CORNER THIS CORNER SHOULD BE 5 8 1 8 HIGHER THAN DRAIN CORNER Figure 14 Sloping the Unit for Proper Drainage INSTALL CONDENSATE DRAIN The air handler is equipped with NPT condensate drain connections IMPORTANT On some pans the primary and secondary drain holes have knockouts Confirm primary and secondary drains a...

Страница 9: ...PE IN HALF AND USE IT TO ROUTE THE MAIN DRAIN Figure 16 Typical Main and Overflow Drain 2 Install properly sized field provided connection fittings and connect primary drain line to the main drain pan connection NOTE When installing drain line connection fittings to the drain pan hand tighten the fitting and use a thread sealant Over tightening the fittings can split connections on the drain pan 3...

Страница 10: ...rs have a higher static pressure drop than standard efficiency glass foam filters If the pressure drop is too great system capacity and performance may be reduced The pressure drop may also cause the limit to trip more frequently during the winter and the indoor coil to freeze in the summer result ing in an increase in the number of service calls Before using any filter with this system check the ...

Страница 11: ...ntroduction of moisture into a system NOTE When installing refrigerant lines longer than 50 feet see the Lennox Refrigerant Piping Design and Fabrication Guidelines CORP 9351 L9 or contact Lennox Technical Support Product Applications for assistance To obtain the correct information from Lennox be sure to communicate the following information Model and capacity 1 Route the suction and liquid lines...

Страница 12: ...TO ALLOW FILTER ACCESSIBILITY NOTE CBX25UHV SERIES UNITS USE NITROGEN OR DRY AIR AS A HOLDING CHARGE IF THERE IS NO PRESSURE WHEN THE RUBBER PLUGS ARE REMOVED CHECK THE COIL FOR LEAKS BEFORE INSTALLING REFER TO INSTRUCTIONS PROVIDED WITH OUTDOOR UNIT FOR LEAK TESTING EVACUATING AND CHARGING PROCEDURES FLOW REGULATED NITROGEN AT 1 TO 2 PSIG THROUGH THE REFRIGERATION GAUGE SET INTO THE VALVE STEM PO...

Страница 13: ... through specified low voltage opening Run line voltage wiring only through specified high voltage opening Do not combine voltage in one opening WARNING Electric Shock Hazard Can cause injury or death Foil faced insulation has conductive characteristics sim ilar to metal Be sure there are no electrical connections within a of the insulation If the foil faced insulation comes in contact with electr...

Страница 14: ...ical unit wiring as well as wiring of optional field installed electric heat is given in figure 21 Refer to the instructions provided with the electric heat section for proper installation See figure 22 for typical low voltage field wiring connections WARNING USE COPPER CONDUCTORS ONLY 1 Disconnect all power supplies 2 Remove the air handler access panel 3 Route the field supply wires to the air h...

Страница 15: ...O 104796 01 12 BLK 12 BLK 1 2 3 4 5 1 2 3 4 5 6 8 9 10 11 12 13 14 15 7 1 2 3 4 5 6 8 9 10 11 12 13 14 15 7 16 Y2 DS O W1 W2 Y1 G 14 RED L2 18 BLUE L2 18 WHITE L2 18 BLACK L2 R CIRCUIT BOARD MOTOR TR BR GRD 18 YEL 18 ORG 18 PRPLE 18 BLUE WHITE 18 GRN 18 RED 18 WHITE 18 BLK 18 RED 18 YEL 18 BLUE 18 RED 18 RED 18 YEL 14 YEL 14 YEL 14 BLK 18 WHITE 18 WHITE 18 WHITE 18 WHITE 18 WHITE 18 WHITE 18 WHITE...

Страница 16: ...Page 16 WARNING USE COPPER CONDUCTORS ONLY Figure 22 Low Voltage Connections Variable Speed Motor ...

Страница 17: ...er speed needed to meet application CFM requirements JUMPER SETTINGS IMPORTANT Before changing jumper setting make sure the motor has completely stopped Any jumper setting change will not take place while the motor is running Table 2 lists the recommended factory blower speed tap selections for Merit CBX25UHV series units These settings are for nominal tonnage match ups with the Merit CBX25UHV Whe...

Страница 18: ...ormance tables With the thermostat set for Continuous Fan and without a call for heating or cooling the Merit CBX25UHV provides 50 of the COOL CFM selected NOTE For two stage heat pumps air handler will operate at 70 of the COOL selection until supplemental electric heat is demanded At that time the air handler will operate at the selected HEAT speed This arrangement provides warmer supply air dur...

Страница 19: ... cfm 880 1115 1345 1435 615 770 930 1090 880 1110 1340 1435 NORM 800 1010 1215 1425 555 695 845 990 795 1005 1215 1420 715 905 1095 1275 505 625 755 885 715 905 1090 1280 NOTES The effect of static pressure filter and electric heater resistance is included in the air volumes listed First stage cooling air volume is 70 of COOL second stage speed setting Continuous blower speed is approximately 50 o...

Страница 20: ...COOL second stage speed setting Continuous blower speed is approximately 50 of COOL speed setting Lennox Harmony III Zoning System applications minimum blower speed is 450 cfm Table 10 Merit CBX25UHV Thermostat and Single Stage Outdoor Unit Operating Sequence Operating Sequence System Demand System Response System Condition Step Thermostat Demand Relative Humidity Com pressor Air Handler CFM COOL ...

Страница 21: ...ndent of a Y1 thermostat demand Normal Operation 1 On On On On Acceptable 24 VAC High 100 Dehumidification mode begins when hu midity is greater than set point Dehumidification Call 2 On On On On Demand 0 VAC High 60 65 70 Dehumidification Call ONLY 1 On On On On Demand 0 VAC High 60 65 70 Thermostat will try to maintain room hu midity setpoint by allowing the room space to maintain a cooler room ...

Страница 22: ... indoor units should come on immediately Check the airflow from a register to confirm that the system is moving cooled air Set the thermostat 5ºF higher than the indoor temperature The indoor blower and outdoor unit should cycle off Air handler should cycle off 45 seconds after the outdoor unit shuts off CHECK ELECTRIC HEATER IF USED Set thermostat to call for auxiliary heat approximately 5 F abov...

Страница 23: ...must be taped with a similar foil faced tape 1 CUT INSULATION IN X PATTERN 2 APPLY GLUE 3 PRESS GLUED TABS AGAINST CABINET GLUE Make sure there is full coverage of glue on the metal or insulation so there are no areas where air pockets may form which can lead to sweating Figure 24 Repairing Insulation Use of Air Handler During Construction Lennox does not recommend the use of its air handler unit ...

Страница 24: ...n Duct Temperature ___________ THERMOSTAT Adjusted and Programmed Return External Static ______ ______ Total External Static ______ ______ 6 Supply Duct Temperature ___________ Temperature Drop ___________ TEMPERATURE RISE Heating Mode Return Duct Temperature __________ Supply Duct Temperature __________ Temperature Rise __________ Operation Explained to Owner 9 Explained Operation of System to Ho...

Страница 25: ...___ Total External Static ______ ______ 6 6 Supply Duct Temperature ___________ Temperature Drop ___________ TEMPERATURE RISE Heating Mode Return Duct Temperature __________ Supply Duct Temperature __________ Temperature Rise __________ Operation Explained to Owner 9 Electric Heat Amps 7 Explained Operation of System to Homeowner Technician s Name _______________________Date Start Up Performance C...

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