61
TROUBLESHOOTING
Table 10.2: Blocking Errors
Error
Number
Error Display
Corrective Actions
100
WD_ERROR_RAM
Internal software error. If error persists, replace control.
101
WD_ERROR_ROM
Internal software error, If error persists, replace control.
102
WD_ERROR_STACK
Internal software error. If error persists, replace control.
103
WD_ERROR_REGISTER
Internal software error. If error persists, replace control.
104
WD_ERROR_XRL
Internal software error. If error persists, replace control.
105
HIGH_TEMP_ERROR
T_Supply and T_Supply_2 over High limit temperature of 190°F
106
REFHI_TOO_HIGH
Internal hardware error. If error persists, replace control.
107
REFHI_TOO_LOW
Internal hardware error. If error persists, replace control.
108
REFLO_TOO HIGH
Internal hardware error. If error persists, replace control.
109
REFLO_TOO_LOW
Internal hardware error. If error persists, replace control.
110
REFHI2_TOO_HIGH
Internal hardware error. If error persists, replace control.
111
REFHI2_TOO_LOW
Internal hardware error. If error persists, replace control.
112
REFLO2_TOO_HIGH
Internal hardware error. If error persists, replace control.
113
REFLO2_TOO_LOW
Internal hardware error. If error persists, replace control.
114
FALSE_FLAME
Flame detected in a state in which no flame should be present.
– Check flame sensor for a short to ground. Replace sensor, sensor gasket or harness if
short is found.
– Check solenoid on gas valve for operation. Gas valve might not be closing properly.
Replace gas valve.
117
BLOCKED_DRAIN
Blocked drain switch is active/Open float switch circuit in condensate collector cap
– Check for blockages in the condensate system inside or after the condensate trap.
– A slow drainage of condensate could cause condensate back up that will trip this switch
under certain conditions.
– Clean condensate system.
– Check for broken wires or bad connections.
118
WD_COMM_ERROR
Watchdog communication error. If error persists, replace control.
119
RETURN_OPEN
Return Sensor open
– Check sensor wiring for solid connection and continuity. Replace harness if wiring is bad.
– Check for resistance though the sensor by touching meter leads across both pins on the
sensor. If no circuit is present, replace sensor.
120
SUPPLY_OPEN
Supply Sensor 1 open
– Check sensor wiring for solid connection and continuity. Replace harness if wiring is bad.
– Check for resistance though the sensor by touching meter leads across the left two pins
on the sensor using when the retaining clip is towards you. If no circuit is present replace
sensor.
121
SUPPLY2_OPEN
Supply Sensor 2 open
– Check sensor wiring for solid connection and continuity. Replace harness if wiring is bad.
– Check for resistance though the sensor by touching meter leads across the right two pins on
the sensor using when the retaining clip is towards you. If no circuit is present replace sensor.
122
DWH_OPEN
DHW Sensor open
– Check sensor wiring for solid connection and continuity. Replace harness if wiring is bad.
– Check for resistance though the sensor by touching meter leads across both pins on the
sensor. If no circuit is present replace sensor.
123
FLUE_OPEN
Flue Sensor open
– Check sensor wiring for solid connection and continuity. Replace harness if wiring is bad.
– Check for resistance though the sensor by touching meter leads across both pins on the
sensor. If no circuit is present replace sensor.
