Honeywell 7800 Series Installation Instructions Manual page 8

7800 SERIES RM7896D RELAY MODULE
Table 3. RM7896D1027 Blinking Fault Codes and Recommended Troubleshooting.
Fault Code System Failure
Code 1-1 Low AC line detected.
*Low AC Line
Voltage*
Code 1-2 Excessive noise or
*AC Quality device running on slow,
Problem* fast, or AC line dropout
detected.
Code 2-1 Flame sensed when no
*Unexpected flame is expected
Flame Signal* during STANDBY or
PURGE.
Code 2-2 No-flame time present
*Flame Signal at the end of the Pilot
Absent* Flame Establishing
Period; lost during the
Main Flame
Establishing Period or
during Run.
Code 2-3 Flame signal value is
*Flame Signal too high to be valid.
Overrange*
Code 3-1 Lockout interlock fault
*Running/ during Prepurge.
Interlock
Switch
Problem*
32-00208-01
Recommended Troubleshooting
1. Check the relay module and display module connections.
2. Reset and sequence the RM7896.
3. Check the 7800 power supply and make sure that frequency and voltage
meet specifications.
4. Check the backup power supply, as appropriate.
1. Check that flame is not present in the combustion chamber; correct any
errors.
2. Make sure that the flame amplifier and flame detector are compatible.
3. Check the wiring and correct any errors.
4. Remove the flame amplifier and inspect its connections. Reseat the ampli-
fier.
5. Reset and sequence the RM7896D.
6. If the code reappears, replace the flame amplifier and/or the flame detec-
tor.
7. If the fault persists, replace the relay module.
1. Measure the flame signal. If one exists, verify that it meets specifications.
2. Make sure that the flame amplifier and flame detector are compatible.
3. Inspect the main fuel valve(s) and valve connection(s).
4. Verify that the fuel pressure is sufficient to supply fuel to the combustion
chamber. Inspect the connections to the fuel pressure switches. make sure
they are functioning properly.
5. Inspect the Airflow Switch and make sure that it is functioning properly.
6. Check the flame detector sighting position; reset and recycle. Measure the
flame signal strength. Verify that it meets specifications. if not, refer to the
flame detector and/or flame amplifier checkout procedures in the
installation instructions.
7. Replace the flame amplifier and/or the flame detector, if necessary.
8. If the fault persists, replace the relay module.
1. Make sure the flame detector and flame amplifier are compatible.
2. Remove the flame amplifier and inspect its connections. Reset the flame
amplifier.
3. Reset and sequence the RM7896D.
4. Check the flame detector sighting position; reset and recycle. Measure
flame strength. Verify that it meets specifications. If not, refer to the flame
detector and/or flame amplifier checkout procedures in the installation
instructions.
5. If the code reappears, replace the flame amplifier and/or the flame detec-
tor.
6. If the fault persists, replace the relay module.
1. Check wiring; correct any errors.
2. Inspect the fan; make sure there is no air intake blockage and that it is
supplying air.
3. Make sure the Lockout Interlock switches are functioning properly and the
contacts are free from contaminants.
4. Reset and sequence the RM7896D to Prepurge (place the TEST/RUN
switch in the TEST position, if available). Measure the voltage between ter-
minal 7 and G (ground); 120 Vac should be present.
5. If steps 1 through 4 are correct and the fault persists, replace the relay
module.
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