16
7800 SERIES RELAY MODULES
65-0229—1
Table 3. Hold and Fault Message Summary (continued).
Fault Code System Failure Recommended Troubleshooting
Fault 51
*Flame Too Strong* Flame signal value is too high
to be valid. 1. Make sure that flame detector and flame amplifier are
compatible.
2. Remove the flame amplifier and inspect the connections. Reset
the flame amplifier.
3. Reset and sequence the relay module.
4. Check the flame detector sighting position, reset and cycle.
5. Verify that no ignition noise is present in the F lead due to wire
routing.
6. Measure the flame strength. Verify it meets specifications. If
not, refer to the flame amplifier and/or flame detector checkout
procedures.
7. If the code reappears, replace the flame amplifier and/or the
flame detector.
8. If the fault persists, replace the relay module.
Fault 52
*Call Service* Pilot Valve 2 (terminal 21) was
off when it should be on. 1. Inspect terminal 21 and connections. Make sure that the valve
is operating properly.
2. Reset and sequence the relay module.
3. If the fault persists, replace the relay module.
Fault 53
*Lockout Switch* Lockout Input fault
(EC/RM7810, 7820, 7830,
7850 only).
1. Check wiring; correct any errors.
2. Inspect the Lockout Switch to make sure it is working
properly.
3. Reset and sequence the relay module. During STANDBY or
PREPURGE, measure the voltage between terminal 20 and G
(ground). Supply voltage should be present. If not, the
lockout switch is defective and needs replacing.
4. If the fault persists, replace the relay module.
Fault 54
*Comb. Pressure* Combustion pressure switch
fault (Fulton pulse only). 1. Check wiring; correct any errors.
2. Inspect the Combustion Pressure Switch to make sure it is
working correctly.
3. Reset and sequence the relay module.
4. During STANDBY or PREPURGE, measure the voltage
between terminal 20 and G (ground). Supply voltage should
be present. If not, the Combustion Pressure Switch is
defective and needs replacing.
5. If the fault persists, replace the relay module.
Fault 55
*Purge Fan Sw. On* Purge fan switch is on when it
should be off (Fulton pulse
only).
1. Check wiring; correct any errors.
2. Inspect the Purge Fan Switch terminal 18 and its connections.
Make sure the switch is working correctly and is not jumpered
or welded.
3. Reset and sequence the relay module.
4. If the fault persists, replace the relay module.
Fault 56
*Block Intake* Block intake fault
(Fulton pulse only). 1. Check wiring; correct any errors.
2. Inspect the Block Intake Switch and make sure it is working
properly.
3. Reset and sequence the relay module.
4. During PREPURGE, measure the voltage between terminal 7
and G (ground). Supply voltage should be present. If not, the
Block Intake Switch is defective and needs replacing.
5. If the fault persists, replace the relay module.
Fault 57
*Purge Fan Sw. Off* Purge Fan Switch is off when
it should be on (Fulton pulse
only).
1. Inspect the Prepurge Fan Switch terminal 18 and the
connections. Make sure the switch is working properly.
2. Reset and sequence the relay module.
3. If the fault persists, replace the relay module.
Faults 58 - 66
*Call Service* Unused faults
Fault 67
*AC Phase* L1 and L2
miswired/exchanged
(EC/RM7810, 7820, 7830,
7850 only).
1. Check L1 and L2 for proper line phasing.
(continued)