Lennox XP17-024-230-01 Installation And Service Procedure page 20

Table 8. One Stage — Fan Motor Control RPM Jumper Settings, LED RPM Indicator and P2 DC
Model LED Code*
XP17-024
XP17-030
XP17-036, -042
XP17-048, -060
* LED Code indicates fan motor control LED flash sequence. For example, LED Code 9 indicates 9 slow flashes and pause.
Unit Status
Mismatched RPM
CRC Failure
Unit Status
One Stage Operation
RPM Indicator
NOTE — There is a long pause between stage
operation and RPM indicator. See tables 1 and 2
for LED RPM indicator.
Flash Flash = Three flashes per second.
Slow Flash = One flash per second.
Short Pause = Two seconds of OFF time.
Long Pause = Five seconds of OFF time.
DEMAND
BEGINS
MISMATCHED
RPM
CRC FAILURE
SINGLE STAGE
YES
OR EDA
OPERATION
DEMAND
ENDED
Figure 8. Fan Motor Control One Stage LED Sequence of Operation
XP17
4
5 OFF
6 OFF
8 OFF
9 OFF
Table 9. Fan Motor Control Error/Fault LED Codes
Fan Motor Control LED
Fast Flash with no pause
Table 10. Fan Motor Control (A177) Unit LED Codes
Unit Status
Low Stage — ECM1/Y1 ONLY
RPM Indicator
DEFAULT FAN
MOTOR SPEED
USED
DEFAULT FAN
MOTOR SPEED
USED
ECM1/Y1
ONLY OR
ECM2/Y2
ONLY
NO
Voltage Outputs
CFM Profile Pin Select
3 2
ON ON
ON ON
OFF ON
OFF OFF
Constant ON.
LED CONTINUOUS FAST
FLASH
LED CONSTANT ON
FAN MOTOR
RPM SET PER
JUMPER
SETTINGS
Page 20
ECM1/Y1
1 RPM
ON 400
OFF 450
ON 600
ON 675
Possible Cause
Internal feedback, PWM does not match
target.
Microcontroller CRC failure.
Fan Motor Control LED
One slow flash, then short pause.
Appropriate number of flashes (See tables 8
and 2).
REPLACE FAN MOTOR
CONTROL BOARD
REPLACE FAN MOTOR
CONTROL BOARD
STAGE LED INDICATOR: ONE
SLOW FLASH AND ONE
SHORT PAUSE FOR SINGLE
STAGE OR EDA OPERATION
LED RPM INDICATOR:
EXAMPLE: (2−TON
UNIT) – 5 SLOW
FLASHES AND ONE
LONG PAUSE
(J2) DC Volt
12.7
14.3
19.2
21.6