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LAARS Heating Systems
Page 36
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
49 Maximum cycle count
Control operates correctly,
continued next page >
Содержание LMH
Страница 42: ...LAARS Heating Systems Page 40 Figure 28 Panel Assembly Door Top...
Страница 43: ...Mascot II Boilers and Water Heaters Page 41 Figure 29 Panel Assembly Door Middle...
Страница 44: ...LAARS Heating Systems Page 42 Figure 30 Panel Assembly Door Bottom...
Страница 45: ...Mascot II Boilers and Water Heaters Page 43 Figure 31 Base Jacket Assembly...
Страница 46: ...LAARS Heating Systems Page 44 Figure 32 Heat Exchanger Cabinet Fan...
Страница 47: ...Mascot II Boilers and Water Heaters Page 45 Figure 33 Heat Exchanger Burner Components...
Страница 48: ...LAARS Heating Systems Page 46 Figure 34 Pump Assembly Components...
Страница 49: ...Mascot II Boilers and Water Heaters Page 47 Figure 35 Plumbing Components...
Страница 50: ...LAARS Heating Systems Page 48...
Страница 51: ...Mascot II Boilers and Water Heaters Page 49...