Honeywell 7800 Series Product Data page 19

Fault Code
Fault 32 Combustion Airflow Interlock
*Airflow Switch* fault.
Fault 33 Preignition Interlock fault.
*Preignition ILK*
Fault 34 CTL input was energized at the
*Control On* wrong time for the relay
module. This fault implies a
field wiring error.
Fault 35 Safety relay was off when it
*Call Service* should be on or the internal
fuse has blown.
Fault 36 Main valve terminal was off
*Call Service* when it should be on, or the
internal fuse has blown.
Fault 37 Pilot (ignition) valve terminal
*Call Service* was off when it should be on, or
the internal fuse has blown.
Fault 38 Ignition terminal was off when it
*Call Service* should be on, or the internal
fuse has blown.
Fault 39 V2S valve terminal (usually
*Call Service* terminal 21) was off when it
should be on, or the internal
fuse has blown.
Fault 40 Safety relay was on when it
*Call Service* should be off.
Fault 41 Main valve terminal was on
*Main Valve On* when it should be off.
Fault 42 Pilot (ignition) valve terminal
*Pilot Valve On* was on when it should be off.
Fault 43 Ignition terminal was on when it
*Ignition On* should be off.
Fault 44 V2S valve terminal, used as a
*Pilot Valve 2 On* pilot, is on when it should be off.
Table 7. Hold and Fault Message Summary (Continued).
System Failure
19
7800 SERIES S7800A KEYBOARD DISPLAY MODULE
Recommended Troubleshooting
1. Check wiring and correct any errors.
2. Inspect the fan; make sure there is no blockage of the air
intake and it is supplying air.
3. Make sure the Airflow Interlock Switches are working properly
and all switch contacts are free from contaminants.
4. Reset and sequence the relay module to PREPURGE. Place
the Run/Test Switch in the Test position, if available. Measure
the voltage between terminals 7 and L2(N). Line voltage
should be present.
5. If steps 1 through 4 are correct and the fault persists, replace
the relay module.
1. Check wiring and correct any errors.
2. Inspect the Preignition Interlock switches and make sure they
function 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 20 and L2(N). Line voltage should be
present. If not, the Preignition Interlock switches can be
defective and need replacing.
6. If the fault persists, replace the relay module.
1. Check wiring and correct any errors.
2. Reset and sequence the relay module.
3. If fault persists, replace the relay module.
1. Reset and sequence the relay module. If fault repeats, replace
relay module, but be sure to test for excessive loads on
appropriate terminals described by fault code.
2. If fault does not repeat on next cycle, check for electrical noise
being coupled into the relay module through the loads on
appropriate terminals described by the fault code.
3. Possibly check for bouncing running on Lockout Interlock.
4. If fault persists, replace the relay module.
WARNING
Explosion Hazard.
Can cause severe injury, death or property damage.
1. Remove system power, turn off fuel supply.
2. Check for wiring errors that could provide power to
terminals described by the fault. Correct any errors.
3. Re-power system; reset and sequence the relay module.
4. If fault persists, replace the relay module.
5. When fault is corrected, turn on fuel supply.
65-0090—4