Page 71
N
EO
T
HERM
Boilers and Water Heaters
79
Outlet high limit
H or L
1. Check wiring and correct any possible errors.
2. Replace the outlet high limit.
3. If previous steps are correct and fault persists,
replace the module.
80
DHW (Domestic Hot Water) high
limit
H or L
1. Check wiring and correct any possible errors.
2. Replace the DHW high limit.
3. If previous steps are correct and fault persists,
replace the module.
81
Delta T limit
H or L
1. Check inlet and outlet sensors and pump circuits for
proper operation.
2. Recheck the Delta T Limit to confi rm proper
setting.
3. If previous steps are correct and fault persists,
replace the module.
82
Stack limit
H or L
1. Check wiring and correct any possible errors.
2. Replace the Stack high limit.
3. If previous steps are correct and fault persists,
replace the module.
91
Inlet sensor fault
H
1. Check wiring and correct any possible errors.
2. Replace the Inlet sensor.
3. If previous steps are correct and fault persists,
replace the module.
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
Code
Description
Lockout
or Hold
Procedure
Summary of Contents for NTH
Page 4: ...LAARS Heating Systems...
Page 13: ...Page 9 NEOTHERM Boilers and Water Heaters 38 1 2 98 8 3 4 22 7 1 2 19 64...
Page 30: ...Page 26 LAARS Heating Systems Figure 21 Hydronic Piping Single Boiler Zoning with Circulators...
Page 86: ...Page 82 LAARS Heating Systems Parts Illustration 1 Jacket Components...
Page 88: ...Page 84 LAARS Heating Systems Parts Illustration 4 Internal Components Sizes 750 850...
Page 90: ...Page 86 LAARS Heating Systems Parts Illustration 6 Gas Train Components Sizes 600 850...
Page 93: ...Page 89 NEOTHERM Boilers and Water Heaters Notes...
Page 94: ...Page 90 LAARS Heating Systems Notes...
Page 95: ...Page 91 NEOTHERM Boilers and Water Heaters Notes...
