Honeywell S7800A Installation Manual page 22

7800 SERIES S7800A KEYBOARD DISPLAY MODULE
Fault Code
Fault 56
*Block Intake*
Fault 57
*Purge Fan Sw. Off*
Fault 58
*Comb. Press/Flame*
Fault 59 - 60
*Call Service*
Fault 61
Fault 62
Fault 63
Fault 64
Fault 65
*VPS Off*
Fault 66
*VPS On*
Fault 67
*AC Phase*
Fault 68
*Pre-Ignition ILK*
65-0090-6
Table 7. Hold and Fault Message Summary. (Continued)
System Failure
Block intake fault (Fulton pulse
only).
Purge Fan Switch is off when it
should be on (Fulton pulse
only).
Combustion Pressure Switch or
Flame Sense Fault (Fulton
Pulse Only)
Unused faults.
MV1 Off (Terminal 9); should be
ON.
MV2 Off (Terminal 17); should
be ON.
MV1 ON (Terminal 9); should
be OFF.
MV2 ON (Terminal 17); should
be OFF.
Valve Proving Switch (Terminal
16) OFF; should be ON.
(VPS High Test)
Valve Proving Switch (Terminal
16) ON; should be OFF.
(VPS Low Test)
L1 and L2
miswired/exchanged
(EC/RM7850 only).
Pre-Ignition Interlock fault.
Recommended Troubleshooting
1. Check wiring and correct any errors.
2. Inspect the Block Intake Switch and make sure it is working
properly.
3. Reset and sequence the relay module.
During PREPURGE, measure the voltage between terminal 7
4.
and L2(N). 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.
1. Inspect the Prepurge Fan Switch terminal 18 and the
connections. Make sure the fan is working properly.
2. Reset and sequence the relay module.
3. If the fault persists, replace the relay module.
1. If Combustion Pressure Switch is used - Terminal 20 was On
when it should be Off.
2. If Flame Amplifier is used - Flame sensed when it was not
expected.
3. Check wiring and correct any errors. Make sure flame sensor
wires are run in separate conduits. Check for noise coupling
into flame detector leadwires.
4. Remove and reinstall amplifier.
5. Reset and sequence the relay module.
6. If fault persists, remove Pressure switch connection to terminal
20 or Flame detector wire to F terminal.
7. Reset and sequence the relay module.
8. If fault persists, replace the relay module and reconnect any
removed wires.
-
1. Check wiring and correct any errors.
2. Reset and sequence the control.
3. If fault persists, replace relay module (Before installing the new
relay module, verify current draw of terminal 9).
1. Check wiring and correct any errors.
2. Reset and sequence the control.
3. If fault persists, replace relay module (Before installing the new
relay module, verify current draw of terminal 17).
1. Check wiring and correct any errors.
2. Reset and sequence the control.
3. If fault persists, replace relay module (Before installing the new
relay module, verify current draw of terminal 9).
1. Check wiring and correct any errors.
2. Reset and sequence the control.
3. If fault persists, replace relay module (Before installing the new
relay module, verify current draw of terminal 17).
1. Check wiring and correct any errors.
2. Check MV2 for leaking valve seat.
3. Reset and sequence control.
1. Check wiring and correct any errors.
2. Check MV1 for leaking valve seat.
3. Reset and sequence control.
1. Check L1 and L2 for proper line phasing.
1. Check wiring and correct any errors.
2. Inspect the Pre-Ignition Interlock switches and make sure they
work properly.
3. Check fuel valve operation. Valve must close within five seconds.
4. Reset and sequence the relay module.
5. During STANDBY or PREPURGE, measure the voltage between
terminal 17 and L2(N). Supply voltage should be present. If not, the
Pre-Ignition Interlock switches are defective and need replacing.
6. If the fault persists, replace the relay module.
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