CB780E/CB784E RELAY MODULES WITH VALVE PROVING
750-234
43
32-00150—03
Code 2-2
*Flame Signal
Absent*
No-flame time present
at the end of the PIlot
Flame Establishing
Period; lost during the
Main Flame
Establishing Period or
during RUN.
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 installa-
tion instructions.
7.
Replace the flame amplifier and/or the flame detector, if necessary.
8.
If the fault persists, replace the relay module.
Code 2-3
*Flame Signal
Overrange*
Flame signal value is
too high to be valid.
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 relay module.
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.
Code 3-1
*Running/Inter
lock Switch
Problem*
Running or Lockout
Interlock fault during
Pre-Purge.
1.
Check wiring; correct any errors.
2.
Inspect the fan; make sure there is no air intake blockage and that it is sup-
plying air.
3.
Make sure the Lockout Interlock switches are functioning properly and the
contacts are free from contaminants.
4.
Reset and sequence the relay module to Pre-Purge (place the TEST/RUN
Switch in the TEST position, if available). Measure the voltage between ter-
minal 7 and G (ground); line voltage should be present. Switch TEST/RUN
back to RUN.
5.
If steps 1 through 4 are correct and the fault persists, replace the relay
module.
Code 3-2
*Running/Inter
lock On During
Standby*
Lockout Interlock
powered at improper
point in sequence or
On in Standby.
1.
Check wiring to make sure that the Lockout Interlocks are connected prop-
erly between terminals 6 and 7. Correct any errors.
2.
Reset and sequence the relay module.
3.
If the fault persists, measure the voltage between terminal 6 and G
(ground), then between terminal 7 and G. If there is line voltage at terminal
6 when the controller is off, the controller switch may be bad or is jum-
pered.
4.
If steps 1 through 3 are correct and there is line voltage at terminal 7 when
the controller is closed and the fault persists, check for a welded or jum-
pered Running Interlock or Airflow Switch. Correct any errors.
5.
If steps 1 through 4 are correct and the fault persists, replace the relay
module.
Code 3-3
*VPS in
Improper
State*
VPS (Valve Proving
Switch) in wrong state
during VPS Test.
1.
Check wiring, making sure upstream valve is connected to terminal 9 and
downstream valve is connected to terminal 17.
2.
Conduct Valve Seat leakage test using a manometer.
3.
Reset and sequence the relay module; if fault repeats, test VPS (connected
to terminal 16) is functioning properly; replace if necessary.
4.
Reset and sequence the relay module.
5.
If fault persists, replace the relay module.
Code 4-1
*Purge Card
Problem*
No purge card or the
purge card timing has
changed from the
original configuration.
1.
Make sure the purge card is seated properly.
2.
Inspect the purge card and the connector on the relay module for any dam-
age or contaminants.
3.
Reset and sequence the relay module.
4.
If the fault code reappears, replace the purge card.
5.
Reset and sequence the relay module.
6.
If the fault code persists, replace the relay module.
Table 14. Blinking Fault Codes and Recommended Troubleshooting. (Continued)
Blink Code
System Failure
Recommended Troubleshooting
