LAARS NeoTherm NTV600 - Install and Operating Manual User Manual
Page 52
LAARS Heating Systems
Page 50
CODE# PROBLEM
PROBABLE CAUSE
SOLUTION
COMMON LOCKOUT CODES
27
Internal error
Flame rod to ground
Check wiring / probe grounded, dirty probe
47
Flame rod to ground leakage
Faulty flame detector
Clean or replace flame detector
49
24VAC voltage low/high
Faulty transformer
Check/correct supply line voltage; replace faulty
transformer
52
Motor tachometer fault
Faulty fan / fan wiring
Check fan harness wiring for continuity; replace faulty
fan circuit
53
AC inputs phase reversed
Reverse 24V hot/neutral - use common ground
61
Anti short cycle
Call for heat will be held
Change ASC timer setting
until timer resets
62
Fan speed not proved
Dirty / defective fan
Clean or replace fan; check wiring
63
LCI off
Safety chain interrupt
Check flow switch, aux high limit, LWCO, gas
pressure switches, condensate level and correct
problem
69
Outlet high limit
High limit tripped
Determine cause: low/no flow, valves closed, settings
and correct
79
Outlet high limit
80
DHW high limit
High limit reached
Check pump, time delay, valves closed, etc. and
81
Delta T inlet/outlet limit
correct overtemp
82
Stack limit
High limit reached
Could be caused by high ambient temperature, or
high return water temperature
88
Outlet T-rise limit
90
Heat exchanger high limit
High limit reached
Diagnose / repair cause of high temperature
91
Inlet sensor fault
92
Outlet sensor fault
93
DHW sensor fault
Faulty sensor or wiring
Check wiring / replace sensor; condition can be
95
Stack sensor fault
caused by short
96
OAT temperature sensor fault
Faulty outdoor air
Check wiring and sensor for short; replace sensor
temperature sensor
is open or shorted
105
Flame detected
Flame exists at burner
Clean burner of soot or other debris that could
out of sequence
when it should not be
maintain flame
106
Flame lost in MFEP
Unstable flame during
107
Flame lost early in Run
lighting / flame proving
Check venting, gas supply pressure, burner, fan, etc.
108
Flame lost in Run
sequence
109
Ignition failed
Problem with ignitor, or
Check / replace ignitor, wiring; check for shorting
other ignition-related device
in ignitor cable
113
Flame circuit timeout
Flame not established
Check all combustion components; purge gas;
within expected time limit
check ignition source
122
Lightoff rate proving failed
123
Purge rate proving failed
128
Fan speed failed / prepurge
Fan did not reach
Check fan wiring; replace fan
129
Fan speed failed / preignition
expected RPM
130
Fan speed failed / ignition
131
Fan movement detected
Fan should not be moving
Check for common venting problems or otherwise
during standby
when not powered
forced air
132
Fan speed failed during run
Fan lost or gained speed
Fan overheating or otherwise failing; check cable;
during run sequence away
replace fan
from control spec
137
ILK failed to close
No power at interlock ILK
Check J5 pin 1 for power - if no power, confirm
safeties are closed
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