Install Instructions

Page 69
NEOTHERM Residential Boilers
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 con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
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, replace the
module.