Carrier F96CTN Installation, Start-Up, Operating, Service And Maintenance Instructions Download Page 61

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F96CTN and G96CTN (Series A): Installation, Start-up, Operating, Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

General

These instructions are written as if the furnace is installed in an upflow

application. An upflow furnace application is where the blower is

located below the combustion and controls section of the furnace, and

conditioned air is discharged upward. Since this furnace can be installed

in any of the 4 positions shown in

Fig. 2

, you must revise your

orientation to component location accordingly.

Electrical Controls and Wiring

Each pressure switch is labeled with the reference location (noted as

“COLLECTOR BOX-LPS” or “HOUSING-HPS” on the switch). The

nominal break point of each switch is shown on the label below the

reference location in inches of water column, “W.C.” The maximum and

minimum break point of the switch is +/- 0.05 inches of water column

from the nominal break point of the switch. The maximum make point of

the switch is 0.10 inches of water above the maximum break point of the

switch.

Example

: Nominal break point on pressure switch is 0.68-in. W.C. The

minimum break point of the switch is 0.63-in. W.C. The maximum break

point of the switch is 0.73-in. W.C. The maximum make point of the

switch is 0.83-in. W.C.

The electrical ground and polarity for 115-v wiring must be properly

maintained. Refer to

Fig. 36

for field wiring information and to

Fig. 73

for furnace wiring information.

NOTE:

If the polarity is not correct, the STATUS LED on the control

will flash rapidly (Status Code 10) and prevent the furnace from heating.

The control system also requires an earth ground for proper operation of

the control and flame-sensing electrode.
The 24-v circuit contains an automotive-type, 3-amp. fuse located on the

control. See

Fig. 38

. Any shorts of the 24-v wiring during installation,

service, or maintenance will cause this fuse to blow. If fuse replacement

is required, use ONLY a 3-amp. fuse. The control LED will be off when

fuse needs to be replaced.

Troubleshooting

Refer to the service label. See

Fig. 66

The Troubleshooting Guide can be a useful tool in isolating furnace

operation problems. Beginning with the word “Start,” answer each

question and follow the appropriate arrow to the next item. See

Fig. 72

The Guide will help to identify the problem or failed component. After

replacing any component, verify correct operation sequence.
Proper instrumentation is required to service electrical controls. The

control in this furnace is equipped with a Status Code LED

(Light-Emitting Diode) to aid in installation, servicing, and

troubleshooting. Status codes can be viewed at the indicator in blower

door. The amber furnace control LED is either ON, flashing a heartbeat,

off or a code composed of 1 or 2 digits. The first digit is the number of

short flashes, the second digit is the number of long flashes.
For an explanation of status codes, refer to service label located on

control door or

Fig. 66

, and the troubleshooting guide which can be

obtained from your distributor.

Retrieving Stored Fault Codes

The stored status codes will NOT be erased from the control memory,

when 115- or 24-v power is interrupted. The control will store up to the

last 7 Status Codes in order of occurrence.

1. To retrieve status codes, proceed with the following:

NOTE:

NO thermostat signal may be present at control, and all

blower-OFF delays must be completed.

a. Leave 115-v power to furnace turned on.

b. Look into blower door indicator for current LED status.

c. Remove blower door.

NOTE:

The Status Codes cannot be retrieved by disconnecting the limit

switch. To retrieve Status Codes, follow the procedure below.

2. Turn Setup Switch, SW1-1 “ON.”
3. Manually close blower door switch.
4. Control will flash up to 7 Status Codes.
5. The last Status Code, or 8th Code, will be a brief heartbeat.
6. Turn SW1-1 “OFF.”
7. The Amber LED will flash a heartbeat (bright-dim) continuously to

indicate proper operation.

8. Release blower door switch, install blower door and refer to the

SERVICE label on the control door for more information.

Component Self-Test

Component Test can ONLY be initiated by performing the following:

1. Remove blower door.
2. Remove the wire from the “R” terminal of the control board.
3. Turn Setup Switch, SW-1-6 “ON.”
4. Manually close blower door switch.

Blower door switch opens 115-v power to control. No component

operation can occur unless switch is closed. Caution must be taken when

manually closing this switch for service purposes.

CAUTION

ENVIRONMENTAL HAZARD

Failure to follow this caution may result in environmental pollution.
Remove and recycle all components or materials (i.e. oil, refrigerant,

control board, etc.) before unit final disposal.

WARNING

ELECTRICAL SHOCK, FIRE OR EXPLOSION HAZARD

Failure to follow this warning could result in personal injury or death,

or property damage.

Before installing, modifying, or servicing system, main electrical