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035-19643-001 Rev. B (0204)

Unitary Products Group

7

COOLING AIRFLOW

The cooling airflow is preset at the factory to provide approximately 90
percent of the maximum CFM and must be field adjusted to match the
HVAC system at installation. Refer to the outdoor unit installation
instruction for the recommended airflow for the cooling system.

Delay Taps Selection on the CFM / Timer Board

Pin Position A: 

is the factory setting and is used for test purposes. The

blower will operate at 100% of the programmed cooling air flow for 60
seconds, with a 15 second coast to stop.

Pin Position B: 

is for a two-stage condenser. This results in a 45 sec-

ond off delay at 82% of the programmed cooling airflow with a 15-sec-
ond coast to stop

Pin Position C: 

is for a system with a TXV or solenoid valve. This

results in a 45 second off delay at 75% of the programmed cooling air-
flow with a 15-second coast to stop.

Pin Position D: 

Is for a system without a TXV or solenoid valve. This

results in a 60 second off delay at 82% of the programmed cooling air-
flow with a 15-second coast to stop.

Cool and ADJ Taps Selection on the CFM / Timer Board

Pin Position A, B, C, and D: 

The pin settings are dependent on the

model furnace and the CFM that is desired for your application. Table
16 in the installation manual has two columns under each model fur-
nace. These columns are the high / low speed CFM options for each
model. On the right side of the table there are two columns labeled
“COOL TAP” and “ADJ TAP”. Find the model furnace you have, scroll
down the high / low columns until you come to the desired CFM, then
go to the last two columns in that row to find the recommended “COOL
TAP” and “ADJ TAP” settings. Once you have found the settings, go to
the CFM / Timer Board. Under “TAP SELECTION” you will see a col-
umn labeled “COOL” and one labeled “ADJ”. Place the PINS on the
proper COOL setting and the proper ADJ setting that you found in the
table. Refer to Figure 7 for the location COOL, HEAT, DELAY and ADJ
TAP SELECTIONS and the pin positions on the CFM / Timer Board.

DIRECT DRIVE BLOWER MOTOR

A failed variable speed motor should always be replaced with a variable
speed motor suitable for the furnace model being serviced. However, if
one is not available, a direct-drive multi speed blower motor can be
used as a 

TEMPORARY REPLACEMENT MOTOR

 in the interim.

Removal of the Variable Speed Blower Motor Assembly:

The procedure for removing the variable speed blower assembly:

1.

Disconnect the electrical supply to the furnace and remove the
access doors.

2.

Remove blower assembly mounting screws and slide the blower
assembly out of the slots in the deck. If the two shipping screws
were not previously removed, also remove and discard these two
screws located on each front corner of the blower assembly.

3.

Loosen the blower wheel set screw that secures the blower wheel
to the blower motor shaft.

4.

Remove the motor mount bolts.

5.

Slide the variable speed motor out of the blower housing.

Reassembly of the Variable Speed Blower Motor Assembly:

1.

Slide the new variable speed motor in to the blower housing. Make
sure you line up the flat side on the motor shaft with the setscrew
on the hub in the center of the blower wheel. 

2.

Install the motor mount bolts in to the fan housing.

3.

Center the indoor fan wheel in the fan housing and tighten the
blower wheel set screw on the flat side the blower motor shaft.

4.

Reinstall blower assembly mounting screws and slide the blower
assembly back in the slots in the deck. Do not reinstall the two
shipping screws were removed.

5.

Install the access doors.

6.

Restore power to the furnace and verify operation.

INSTALLATION OF PSC MOTOR:

The motor speed tap wires are connected to the 1/4" quick connect ter-
minal on the Integrated Control using the black jumper wire that is
secured to the wire harness inside the burner compartment and is
marked “PSC Motor”. Follow the instructions below to properly install
the PSC motor.

1.

Install the PSC direct drive motor into motor mount.

2.

Slide motor in motor mount insuring there is no interference
between moving and stationary parts. Position wire leads down-
ward. Tighten motor mount band screw to 30 in. lbs.

3.

Center the blower wheel in the blower housing and align the shaft
flat with the blower wheel set screw. Tighten setscrew to 30 in. lbs.

4.

Replace blower assembly and fasten with 5 screws

5.

Strap motor capacitor to electric panel. Refer to Table 2 for proper
capacitor selection.

6.

Fasten electric panel to blower housing.

7.

Remove red wire from circuit input terminal. Plug jumper wire
(attach to motor power harness) on 120-volt line terminal on igni-
tion control and jumper to circuit Input. Connect brown door switch
wire to jumper.

8.

Connect white main harness lead to Line neutral.

9.

Connect motor leads to cool, heat lo and heat high per electrical
wire diagram table in the Installation manual.

10. Connect brown capacitor leads from motor to capacitor and cover

terminals with boot supplied.

11.

The motor ground (green) wire is secured to the right front of the
blower mounting plate with a screw.

12. Restore power to the furnace and verify operation.

TABLE 2: 

Replacement PSC Motor / Capacitor Information

High Fire Inputs

Airflow

Cabinet Size

Motor 

Part Number

Motor 

Horsepower

Capacitor 

Part Number

Capacitor 

Rating 

BTU/H (kW)

CFM (m³)

80,000 (23.4)

1,200 (33.98)

B

024-23271-000

1/2

024-20045-000

7.5 f

100,000 (29.3)

2,000 (56.63)

C

024-23238-001

1.0

024-20446-000

15.0 f

120,000 (35.1)

2,000 (56.63)

D

024-23238-001

1.0

024-20446-000

15.0 f

Summary of Contents for P XD-V Series

Page 1: ...e fur nace can result in fire or explosion A qualified service agency should be contacted to inspect the furnace and replace all gas controls control system parts electrical parts that have been wet o...

Page 2: ...ng making sure the physical support is sound without sagging cracks or gaps Examine the furnace base making sure it is physically sound without cracks gaps or sagging and has a good seal 5 Examine the...

Page 3: ...e control system and any gas control which has been under water Operating Instructions 1 STOP Read the safety information above 2 Set the thermostat to the lowest setting 3 Turn off all electric power...

Page 4: ...lter after cleaning you must do the following 1 Slide filter into place 2 Snap the door on or place the door in position and tighten the retaining screws if provided 3 Make sure the door is secure to...

Page 5: ...iliary Limit and Roll out Switches for closed contacts The Control checks that the Low Fire Pressure Switch 1LP is open The Inducer Motor is energized on high speed closing the con tacts of 1LP The Co...

Page 6: ...provide the highest CFM Pin Position B and C are the medium and medium low CFM settings Pin Position D will provide the lowest CFM Refer to Table 16 in the installation manual for the proper HEAT Tap...

Page 7: ...s were not previously removed also remove and discard these two screws located on each front corner of the blower assembly 3 Loosen the blower wheel set screw that secures the blower wheel to the blow...

Page 8: ...the conden sate drain pan Remove the vent blower housing blower and the condensate pan The turbulators can then be gently removed from the secondary heat exchanger 3 Using a stiff wire brush remove t...

Page 9: ...by the control Effect Control tries 3 times then goes into Soft Lockout There is a 1 minute delay after a failed ignition attempt 7 seconds is added to the igniter warm up time after a failed ignitio...

Page 10: ...W INDUCER LOW STAGE PRESSURE SWITCH HSI 1ST STAGE MAIN VALVE FLAME SENSE LOW CIRCULATOR HEAT SPEED 1ST STAGE LOW PRESSURE SWITCH CLOSE RECOGNITION HSI WARM UP 17 SEC IGNITION ACTIVATION PERIOD 4 SEC T...

Page 11: ...itary Products Group 11 SECTION III REPLACEMENT PARTS LIST 15 16 1 17 3 7A 13 14 5 8 12 9 2 7 6 6 11 6A 24 27 26 35 38 34 32 33 25 36 22 37 21 20 28 29 23 31 30 18 19 51 63 43 53 59 57 58 55 39 41 52...

Page 12: ...R BURNER BOX 31 COVER HEAT EXCHANGER 32 PANEL FRONT Blower 33 PANEL FRONT Burner 34 PANEL TOP 35 SUPPORT BURNER 36 WRAPPER CABINET 37 PANEL VESTIBULE Lower 38 PLUG WINDOW CLEAR 875 MISCELLANEOUS 39 CO...

Page 13: ...SWITCH KIT DOES NOT INCLUDE ORIFICES FOR APPLICATION INFORMATION SEE FORM 035 14460 000 CONDENSATE NEUTRALIZER KIT ALL MODELS REPLACEMENT PART CONTACT INFORMATION This is a generic parts list To requ...

Page 14: ...035 19643 001 Rev B 0204 14 Unitary Products Group SECTION IV WIRING DIAGRAM FIGURE 10 Wiring Diagram...

Page 15: ...035 19643 001 Rev B 0204 Unitary Products Group 15 NOTES...

Page 16: ...lies only to products installed in the United States and Canada EXCLUSIONS This warranty does not cover any 1 Shipping labor or material charges 2 Damages resulting from transportation installation or...

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