18
LLS
Liquid Line Solenoid
UTILITY RELAY
*
UTILITY SIGNAL
OPEN RELAY
*
SUPPLIED BY UTILITY PROVIDER
A05247
Fig. 17 -- 2--Stage HP/AC Control Board
STATUS CODE 21 -- GAS HEATING LOCKOUT
Control will NOT auto reset. Check for mis--wired gas valve or
defective control (valve relay).
STATUS CODE 22 -- ABNORMAL FLAME--PROVING
SIGNAL
Flame is proved while gas valve is de--energized. Inducer will run
until fault is cleared. Check for leaky gas valve or stuck--open gas
valve.
STATUS CODE 23 -- PRESSURE SWITCH DID NOT OPEN
Check for obstructed pressure tubing or pressure switch stuck
closed.
STATUS CODE 24 -- SECONDARY VOLTAGE FUSE IS OPEN
Check for short circuit in secondary voltage (24VAC) wiring.
STATUS CODE 25 -- INVALID MODEL SELECTION OR
SETUP ERROR
Indicates either the model plug is missing or incorrect. If code
flashes 4 times on power--up, control is defaulting to model
selection stored in memory. Check for proper model plug number
and resistance values per wiring diagram.
STATUS CODE 31, 32 -- PRESSURE SWITCH OR RELAY DID
NOT CLOSE OR REOPENED
Control relay may be defective. If open longer than five minutes,
inducer shuts off for 15 minutes before retry. If open during blower
on--delay period, blower will come on for the selected blower
off--delay. Check for excessive wind, restricted vent, defective
inducer motor, defective pressure switch, lower inducer voltage
(230VAC), inadequate combustion air supply, disconnected or
obstructed pressure tubing, or low inlet gas pressure (if LGPS used).
STATUS CODE 33 -- LIMIT CIRCUIT FAULT
Indicates a limit or flame rollout switch is open. Blower will run for
4 minutes or until open switch remakes, whichever is longer. If open
longer than 3 minutes, code changes to lockout 13. If open less than
3 minutes status code 33 continues to flash until blower shuts off.
Check for loose blower wheel, restricted vent, excessive wind, dirty
filter or restricted duct system, defective switch or connections, or
inadequate combustion air supply (flame roll--out switch open).
STATUS CODE 34 -- IGNITION PROVING FAILURE
Control will try three more times before lockout 14 occurs. If flame
signal lost during blower on--delay period, blower will come on for
the selected blower off--delay. Check for oxide buildup on flame
sensor (clean with fine steel wool), proper flame sense microamps
(.5 microamps D.C. min., 4.0--6.0 nominal), manual valve shutoff,
low inlet gas pressure, control ground continuity, gas valve
defective or turned off, flame sensor must not be grounded,
inadequate flame carryover or rough ignition, or green/yellow wire
must be connected to unit sheet metal.
STATUS CODE 41 -- BLOWER MOTOR FAULT
Indicates the blower failed to reach 250 RPM or the blower failed
to communicate within the prescribed time limits. Thirty seconds
after being turned ON or ten seconds during steady--state operation.
STATUS CODE 45 -- CONTROL CIRCUITRY LOCKOUT
Auto reset after one hour lockout due to gas valve relay stuck open,
flame sense circuit failure, or software check error. Reset power to
clear lockout. Replace control if status code repeats.
E. HP/AC Control Troubleshooting
See Table 5 for HP/AC control board status codes and
troubleshooting information.
STATUS CODE 53, OUTDOOR AIR TEMPERATURE SENSOR
FAULT -- DETAILED DESCRIPTION
If an OAT sensor is found at power--up, input is constantly checked
to be within a valid temperature range. If sensor is found to be open
or shorted at any time after initial validation, Status Code 53 will be
displayed at amber STATUS LED.
Check for faults in wiring connecting sensor to OAT terminals.
Using an Ohm meter, check resistance of thermistor for a short or
open condition.
If thermistor is shorted or open, replace it to return the system to
normal operation. If fault is in the wiring connections, correcting the
fault will clear the code and return the system to normal operation.
NOTE: If fault condition is an open thermistor or a wiring problem
that appears to be an open thermistor and the power to the unit is
48D
U
