Page 90
92
Outlet sensor fault
H
1. Check wiring and correct any possible
errors.
2. Replace the Outlet sensor.
3. If previous steps are correct and fault
persists, replace the module.
93
DHW (Domestic Hot Water)
sensor fault
H
1. Check wiring and correct any possible
errors.
2. Replace the DHW sensor.
3. If previous steps are correct and fault
persists, replace the module.
94
Header sensor fault
H
1. Check wiring and correct any possible
errors.
2. Replace the header sensor.
3. If previous steps are correct and fault
persists, replace the module.
95
Stack sensor fault
H
1. Check wiring and correct any possible
errors.
2. Replace the stack sensor.
3. If previous steps are correct and fault
persists, replace the module.
96
Outdoor sensor fault
H
1. Check wiring and correct any possible
errors.
2. Replace the outdoor sensor.
3. If previous steps are correct and fault
persists, replace the module.
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
99
Internal Fault: Exceeded 28V
voltage tolerance
L
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 Pressure Sensor for correct operation.
4. Replace the Pressure sensor.
5. If previous steps are correct and fault
persists, replace the module.
105
Flame detected out of sequence
H or L
1. Check that fl ame is not present in the
combustion chamber. Correct any errors.
2. Make sure that the fl ame detector is wired to
the correct terminal.
3. Make sure the F & G wires are protected
from stray noise pickup.
4. Reset and sequence the module, if code
reappears, replace the fl ame detector.
5. Reset and sequence the module, if code
reappears, replace the module.
Code
Description
Lockout
or Hold
Procedure
LAARS Heating Systems
Summary of Contents for NEOTHERM NTH
Page 4: ...LAARS Heating Systems ...
Page 36: ...Page 36 Figure 22 Hydronic Piping Single Boiler Zoning with Circulators LAARS Heating Systems ...
Page 52: ...Page 52 Figure 36 Ladder Diagram 7 H Ladder Diagram LAARS Heating Systems ...
Page 100: ...Page 100 Parts Illustration 4 Internal Components Sizes 750 850 LAARS Heating Systems ...
Page 102: ...Page 102 Parts Illustration 6 Gas Train Components Sizes 600 850 LAARS Heating Systems ...