507404-02
Page 70 of 80
Issue 1448
Integrated Control Diagnostic Modes
(Continued)
Code
Diagnostic Codes/Status of Equipment
Action Required to Clear and Recover
E227
Low pressure switch open during
trial for ignition or run mode. Refer to
troubleshooting
Check operation of low pressure switch closing on heat call. Measure
operating pressure (inches w.c.). Inspect vent and combustion air
inducer for correct operation and restriction. Resumes normal operation
after fault is cleared.
E228
Combustion air inducer calibration
failure
Unable to perform pressure switch calibration. Check vent system and
pressure switch wiring connections. Resumes normal operation after
fault is cleared
E229
Ignition on high fire
IFC switched to high fire ignition because low fire pressure switch did
not close in allowed time. No action is needed.
E240
Low flame current - Run mode- Refer
to troubleshooting
Check micro-amperes of flame sensor using control diagnostics or field
installed mode. Clean or replace sensor. Measure voltage of neutral to
ground to ensure good unit ground. Alert clears after current heat all
has been completed.
E241
Flame sensed out of sequence-Flame
still present.
Shut off gas. Check for gas valve leak. Replace if necessary. Alert
clears when fault is recovered.
E250
Limit switch circuit open - Refer to
troubleshooting.
Check for proper firing rate on furnace. Ensure there is no blockage in
heater. Check for proper air flow. If limit not closed within 3 minutes
unit will go into 1 hour soft lockout. Resumes normal operation after
fault is cleared.
E252
Discharge air temperature too high
(gas heat only).
Check temperature rise airflow and input rate. Clear when heat call is
finished.
E270
Soft lockout - Exceeded maximum
number of retries. No flame current
sensed.
Check for proper gas flow. Ensure that igniter is lighting burners. Check
flame sensor current. Clears when heat call finishes successfully.
E271
Soft lockout - Exceeded maximum
number of retries. Last retry failed
due to the pressure switch opening.
Check pressure (inches w.c.) of low pressure switch closing on heat
call. Measure operating pressure (inches w.c.). Inspect vent and com
-
bustion air inducer for correct operation and restriction. Clears when
heat call finishes successfully.
E272
Soft lockout - Exceeded maximum
number of recycles. Last recycle due
to the pressure switch opening
Check operation of low pressure to see if it is stuck closed on heat
call. Check pressure (inches w.c.) of high pressure switch closing on
heat call. Measure operating pressure. Inspect vent and combustion
air inducer for correct operation and restriction. Clears when heat call
finishes successfully.
E273
Soft lockout - Exceeded maximum
number of recycles. Last recycle due
to flame failure
Check micro-amperes of flame sensor using control diagnostics or field
installed mode. Clean or replace sensor. Measure voltage of neutral to
ground to ensure good unit ground. Alert clears after current heat call
has been completed.
E274
Soft lockout - Exceeded maximum
number of recycles. Last recycle
failed due to the limit circuit opening
or limit remained open longer than 3
minutes.
Shut down system 1-hour soft lockout. Check firing rate and air flow.
Check for blockage. Clears when heat call finishes successfully.
E275
Soft lockout - Flame sensed out of
sequence. Flame signal is gone.
Shut off gas. Check for gas valve leak. 1-hour soft lockout. Clears
when flame has been proven stable.
E276 Watchguard calibration failure.
Unable to perform pressure switch calibration. Check vent sys-
tem and pressure switch wiring connections. 1-hour soft lockout.
Clears when calibration has finished successfully.
E290 Ignitor circuit fault - Failed ignitor
or triggering circuitry.
Measure resistance of hot surface igniter. Replace if open or not
within specifications. 1-hour soft lockout. Clears when flame has
been proven stable.
Summary of Contents for A96US2V
Page 3: ...507404 02 Page 3 of 80 Issue 1448 EXPANDED VIEW Figure 1 ...
Page 31: ...507404 02 Page 31 of 80 Issue 1448 Figure 38 ...
Page 38: ...507404 02 Page 38 of 80 Issue 1448 Figure 56 TRAP DRAIN ASSEMBLY USING 1 2 PVC or 3 4 PVC ...
Page 41: ...507404 02 Page 41 of 80 Issue 1448 Table 9 ...
Page 45: ...507404 02 Page 45 of 80 Issue 1448 ...
Page 47: ...507404 02 Page 47 of 80 Issue 1448 Integrated Control Figure 56 ...
Page 78: ...507404 02 Page 78 of 80 Issue 1448 Start Up Performance Check List UNIT SET UP ...
Page 79: ...507404 02 Page 79 of 80 Issue 1448 UNIT OPERATION Heating Mode Cooling Mode ...