User Guide

86
Service Manual NeoTherm 80 - NeoTherm 285
Appendix 1 - Error Codes (continued)
Code Description L or H Procedure
97 Internal fault: A2D mismatch. L Internal Fault.
1. Reset module.
2. If fault repeats, replace module.
98 Internal fault: Exceeded VSNSR voltage
tolerance
L Internal Fault.
1. Reset module.
2. If fault repeats, replace module.
99 Internal fault: Exceeded 28V voltage toler-
ance
L Internal Fault.
1. Reset module.
2. If fault repeats, replace module.
100 Pressure sensor fault H 1. Verify the pressure sensor is a 4-20 ma source.
2. Check wiring and correct any possible errors.
3. Test the pressure sensor for correct operation.
4. Replace the pressure sensor.
5. If previous steps are correct and fault persists, re-
place the module.
105 Flame detected out of sequence H or L 1. Check that ame is not present in the combustion
chamber. Correct any errors.
2. Make sure that the ame detector is wired to the cor-
rect terminal.
3. Make sure the ame and ground wires are protected
from stray noise pickup.
4. Reset and sequence the module, if code reappears,
replace the ame detector.
5. Reset and sequence the module, if code reappears,
replace the module.
106 Flame lost in MFEP (Main Flame Establish-
ing Period)
L 1. Check main valve wiring and operation - correct any
errors.
2. Check the fuel supply.
3. Check fuel pressure and repeat turndown tests.
4. Check ignition transformer electrode, ame detector,
ame detector siting and ame rod position.
5. If steps 1 through 4 are correct and the fault persists,
replace the module.
107 Flame lost early in run L 1. Check main valve wiring and operation - correct any
errors.
2. Check the fuel supply.
3. Check fuel pressure and repeat turndown tests.
4. Check ignition transformer electrode, ame detector,
ame detector siting or ame rod position.
5. If steps 1 through 4 are correct and the fault persists,
replace the module.
App1
cont.