Peerless Boilers · Error codes
Peerless Boilers error codes and alerts
Identical code numbers can mean different things on different controllers, so every entry is tied to the documented series, controller and manual version. A code is never a diagnosis.
If you smell gas
- Stop what you are doing. Do not use phones, switches, matches or anything that can spark inside.
- Go outside and leave the door open behind you.
- Call the FortisBC 24-hour emergency line at 1-800-663-9911 or dial 911.
Only after that, call ROMA about the boiler. Official guidance: FortisBC gas leaks and odour.
Peerless PureFire condensing boilers (E-codes and warnings, IOM PF8248-R9)
E01
SUPPLY SENSOR NOT CONNECTED. Supply sensor not connected (internal 51) - check harness and sensor The table classifies it as blocking.…
Details
E02
RETURN SENSOR NOT CONNECTED. Return sensor not connected (internal 52) - check harness and sensor The table classifies it as blocking.…
Details
E04
DHW SENSOR NOT CONNECTED. DHW sensor not connected (internal 55) - if DHW Mode is not intended to be Mode 1 (DHW Store with Sensor), change …
Details
E05
STACK SENSOR OPEN. Flue gas sensor open (internal 57) - check vent temperature, harness, sensor The table classifies it as blocking.…
Details
E11
SUPPLY SENSOR SHORT. Supply sensor shorted (internal 59) - check harness and sensor The table classifies it as blocking.…
Details
E12
RETURN SENSOR SHORT. Return sensor shorted (internal 60) - check harness and sensor The table classifies it as blocking.…
Details
E13
STACK SENSOR SHORT. Flue gas sensor shorted (internal 65) - check harness and sensor The table classifies it as blocking.…
Details
E14
DHW SENSOR SHORT. DHW sensor shorted (internal 63) - check harness and sensor The table classifies it as blocking.…
Details
E19
COMMUNICATION ERROR E2PROM ERROR. Problems reading from or writing to e2prom (internal 0) - contact PB Heat Representative The table classif…
Details
E20
FALSE FLAME DETECTED. False flame detected (internal 35) - verify no flame in observation port, check sensor The table classifies it as bloc…
Lockout
E21
HOT/NEUTRAL REVERSED. Phase and neutral of mains supply reversed (internal 44) - verify polarity of incoming wiring, check boiler ground and…
Details
E22
POOR GROUND. No earth connected or internal hardware error (internal 43) - check boiler ground and harness The table classifies it as blocki…
Details
E23
NET FREQUENCY ERROR. Mains frequency differs more than 2% from 60Hz (internal 45) - contact electrical provider and/or an electrician The ta…
Details
E24
POOR GROUND. Earth connection is not ok (internal 46) - check boiler ground and harness The table classifies it as blocking.…
Details
E25
BLOCKED VENT. Blocked vent switch is open (internal 38); applies to PF-200, PF-210, PF-300 and PF-399 models - check for blocked vent pipe o…
Details
E26
BLOCKED CONDENSATE DRAIN. Condensate drain blocked (internal 41) - check condensate tanks, hoses, condensate switch, and harness The table c…
Details
E30
HIGH STACK TEMPERATURE. Flue gas sensor above max flue setpoint + diff (internal 39) - if flue pipe is hot compare flue temperature to Table…
Details
E31
LOW WATER. Water level is too low (internal 36) - check boiler water level, low water cut-off, harness; if a LWCO is not used a jumper shoul…
Details
E32
HIGH RETURN TEMP. Return temperature above 194°F (90°C) (internal 40) - check for reversed supply and return piping or pump installed backwa…
Details
E42
INTERNAL HDWRE ERROR. Internal hardware error (internal 47) - see note: disconnect non-factory supplied wires (CH/DHW T'stat, LWCO, pumps); …
Details
E45
INTERNAL HDWRE ERROR. Internal hardware error (internal 31) - see note: disconnect non-factory supplied wires; if error persists replace con…
Details
E46
INTERNAL HDWRE ERROR. Internal hardware error (internal 32) - see note: disconnect non-factory supplied wires; if error persists replace con…
Details
E47
INTERNAL HDWRE ERROR. Internal hardware error (internal 33) - see note: disconnect non-factory supplied wires; if error persists replace con…
Details
E48
INTERNAL HDWRE ERROR. Internal hardware error (internal 34) - see note: disconnect non-factory supplied wires; if error persists replace con…
Details
E51
RESET BUTTON ERROR PLEASE WAIT. Reset button pressed more than 7 times within one minute (internal 66) - wait five minutes; if error does no…
Details
A01
IGNITION ERROR. Three consecutive unsuccessful ignition attempts (internal 1) - watch igniter through observation window; check spark electr…
Lockout
A02
FLAME FAILURE. Three consecutive flame failures during one demand (internal 24) - if sparks/lights briefly then out disconnect flame sensor …
Lockout
A03
OVERHEAT LIMIT OPEN. High temperature limit open, set temperature 205°F (internal 18) - check CH/DHW/general pump operation, adequate flow (…
Details
A04
INTERNAL ERROR GAS VALVE RELAY. Gas valve relay problems (internal 5) - see note: disconnect non-factory supplied wires; if error persists r…
Details
A05
INTERNAL ERROR SAFETY RELAY. Safety relay problems (internal 6) - see note: disconnect non-factory supplied wires; if error persists replace…
Details
A09
INTERNAL SOFTWARE ERR RAM ERROR. Internal software error (internal 9) - see note: disconnect non-factory supplied wires; if error persists r…
Details
A10
COMMUNICATION ERROR E2PROM ERROR. No communication with E2prom (internal 12) - see note: disconnect non-factory supplied wires; if error per…
Details
A12
SOFTWARE OUT OF DATE E2PROM OUT OF DATE. Contents of e2prom is not up-to-date (internal 10) - see note: disconnect non-factory supplied wire…
Details
A13
INTERNAL ERROR. Internal software error (internal 13) - see note: disconnect non-factory supplied wires; if error persists replace control T…
Details
A14
INTERNAL ERROR. Internal software error (internal 14) - see note: disconnect non-factory supplied wires; if error persists replace control T…
Details
A15
INTERNAL ERROR. Internal software error (internal 16) - see note: disconnect non-factory supplied wires; if error persists replace control T…
Details
A16
INTERNAL ERROR. Internal software error (internal 22) - see note: disconnect non-factory supplied wires; if error persists replace control T…
Details
A18
INTERNAL ERROR. Internal software error (internal 19) - see note: disconnect non-factory supplied wires; if error persists replace control T…
Details
A19
FALSE FLAME DETECTED AFTER SHUTDOWN. Flame signal detected 10 sec after closing the gas valve (internal 20) - check flame sensor and igniter…
Lockout
A20
FALSE FLAME DETECTED BEFORE IGNITION. Flame signal detected before gas valve opened (internal 21) - check flame sensor and igniter for short…
Lockout
A23
FLOW_SW_NOT_CLOSED. CH flow switch not working (internal 25) - check for electrical continuity between wires connected to terminals 9 & 10 f…
Details
A24
FLOW_SW_NOT_OPEN. CH flow switch not working (internal 26) - check continuity between terminals 9 & 10; if no continuity check circulator is…
Details
A32
FAN NOT RUNNING. Internal software error (internal 23) - does fan run at full speed after resetting control (check 4-wire connection to blow…
Details
A33
FAN SPEED ERROR. Fan speed detected is more than 300 rpm different from targeted value for more than 60 seconds (internal 8) - check connect…
Details
A50
RETURN HIGHER THAN SUPPLY. Boiler return water temperature higher than supply for more than 5 ignition attempts (internal 11) - check system…
Lockout
#W00
Outdoor Sensor Open. Outdoor sensor open (blinking screen; press Reset to view) - check outdoor sensor connected, wiring connections, remove…
Details
#W01
Outdoor Sensor Shorted. Outdoor sensor shorted (blinking screen) - check wiring; resistance below 3000 ohm between terminals #3/#4 - check r…
Details
#W02
DHW Sensor Open. DHW sensor open (blinking screen) - be sure optional DHW sensor (54157) connected; remove wires from terminals #5 and #6 an…
Details
#W03
DHW Sensor Shorted. DHW sensor shorted (blinking screen) - check wiring connection to DHW sensor; remove wires from terminals #5/#6, check r…
Details
#W04
Flue Sensor Open. Flue sensor open - compare sensor resistance to Figure 8.4 The table classifies it as warning.…
Details
Peerless PBC combi boilers (fault codes, IOM PBC8013-R5)
0
E2PROM_READ_ERROR. Internal software error - replace control The table classifies it as lockout.…
Lockout
1
IGNIT_ERROR. Three unsuccessful ignition attempts in a row - check for spark (120V across blue/brown control output to spark module; if no s…
Lockout
2
GV_RELAY_ERROR. Failure detected in the gas valve relay - replace control The table classifies it as lockout.…
Lockout
3
SAFETY_RELAY_ERROR. Failure detected in the safety relay - replace control The table classifies it as lockout.…
Lockout
4
BLOCKING_TOO_LONG. Blocking error present for more than 20 hours - go to parameter 1052 for last blocking error code, correct cause The tabl…
Lockout
5
FAN_ERROR_NOT_RUNNING. Fan is not running for more than 60 secs - check fan by disconnecting 5 pin control plug (fan should ramp to full pow…
Lockout
6
FAN_ERROR_TOO_SLOW. Fan runs too slow for more than 60 seconds - check voltage to the blower (low voltage = incorrect speed); check continui…
Lockout
7
FAN_ERROR_TOO_FAST. Fan runs too fast for more than 60 seconds - check continuity through blower control harness 5 pin to J4; replace harnes…
Lockout
8
RAM_ERROR. Internal software error - replace control The table classifies it as lockout.…
Lockout
9
WRONG_EEPROM_SIGNATURE. Contents of E2prom is not up to date - replace control The table classifies it as lockout.…
Lockout
10
E2PROM_ERROR. Wrong safety parameters in E2prom - replace control The table classifies it as lockout.…
Lockout
11
STATE_ERROR. Internal software error - replace control The table classifies it as lockout.…
Lockout
12
ROM_ERROR. Internal software error - replace control The table classifies it as lockout.…
Lockout
15
MAX_TEMP_ERROR. Thermal fuse in the main heat exchanger body has tripped (extreme conditions) - replace heat exchanger or entire boiler; che…
Lockout
16
FLUE_GAS_ERROR. Flue temperature exceeded maximum flue temperature limit (192.2°F / 89°C) - lower system setpoint; check temperature delta a…
Lockout
17
STACK_ERROR. Internal software error - replace control The table classifies it as lockout.…
Lockout
18
INSTRUCTION_ERROR. Internal software error - replace control The table classifies it as lockout.…
Lockout
19
ION_CHECK_FAILED. Internal software error - replace control The table classifies it as lockout.…
Lockout
20
FLAME_OUT_TOO_LATE. Flame still present 10 seconds after closing the gas valve - check flame sensor for short to ground (replace sensor, sen…
Lockout
21
FLAME_BEFORE_IGNIT. Flame is detected before ignition - check flame sensor for short to ground, replace sensor/gasket/harness if short found…
Lockout
22
TOO_MANY_FLAME_LOSS. Flame signal lost 3 times during a single demand cycle - clean/replace flame sensor; confirm fuel pressure at valve inl…
Lockout
23
CORRUPTED_ERROR_NR. Error code RAM byte was corrupted to an unknown error code - replace control The table classifies it as lockout.…
Lockout
29
PSM_ERROR. Internal software error - replace control The table classifies it as lockout.…
Lockout
30
REGISTER_ERROR. Internal software error - replace control The table classifies it as lockout.…
Lockout
33
LWCO_1_ERROR. Low water cut off error - if using LWCO probe kit check system for leaks, filling valve operation, wiring and grounding of pro…
Lockout
38
FLUE_PRESSURE_LOCKING. More than 3 blocked flue/condensate switch occurrences in 24 hours - check for blockages in vent pipe or heat exchang…
Lockout
100
WD_ERROR_RAM. Internal software error - if error persists, replace control The table classifies it as blocking.…
Details
101
WD_ERROR_ROM. Internal software error - if error persists, replace control The table classifies it as blocking.…
Details
102
WD_ERROR_STACK. Internal software error - if error persists, replace control The table classifies it as blocking.…
Details
103
WD_ERROR_REGISTER. Internal software error - if error persists, replace control The table classifies it as blocking.…
Details
104
WE_ERROR_XRL. Internal software error - if error persists, replace control The table classifies it as blocking.…
Details
105
HIGH_TEMP_ERROR. T_Supply and T_Supply_2 over stayburn temperature of 190°F The table classifies it as blocking.…
Details
106
REFHI_TOO_HIGH. Internal hardware error - if error persists, replace control The table classifies it as blocking.…
Details
107
REFHI_TOO_LOW. Internal hardware error - if error persists, replace control The table classifies it as blocking.…
Details
108
REFLO_TOO_HIGH. Internal hardware error - if error persists, replace control The table classifies it as blocking.…
Details
109
REFLO_TOO_LOW. Internal hardware error - if error persists, replace control The table classifies it as blocking.…
Details
110
REFHI2_TOO_HIGH. Internal hardware error - if error persists, replace control The table classifies it as blocking.…
Details
111
REFHI2_TOO_LOW. Internal hardware error - if error persists, replace control The table classifies it as blocking.…
Details
112
REFLO2_TOO_HIGH. Internal hardware error - if error persists, replace control The table classifies it as blocking.…
Details
113
REFLO2_TOO_LOW. Internal hardware error - if error persists, replace control The table classifies it as blocking.…
Details
114
FALSE_FLAME. Flame detected in a state in which no flame should be present - check flame sensor for short to ground (replace sensor/gasket/h…
Lockout
115
LOW_WATER_PRESSURE_ERROR. Low water pressure sensor error - replace sensor if error does not correct itself The table classifies it as block…
Details
116
LOW_WATER_PRESSURE_SENSOR. Low water pressure in system - check system pressure, filling valve setting and expansion tank pressure, check sy…
Details
118
WD_COMM_ERROR. Watchdog communication error - if error persists, replace control The table classifies it as blocking.…
Details
119
RETURN_OPEN. Return sensor open - check sensor wiring for solid connection and continuity (replace harness if bad); check for resistance thr…
Details
120
SUPPLY_OPEN. Supply sensor 1 open - check sensor wiring for solid connection and continuity; check for resistance through left two pins of s…
Details
121
SUPPLY2_OPEN. Supply sensor 2 open - check sensor wiring for solid connection and continuity; check for resistance through right two pins of…
Details
122
DWH_OPEN. DHW sensor open - check sensor wiring for solid connection and continuity (replace harness if bad); check resistance across both p…
Details
123
FLUE_OPEN. Flue sensor open - check sensor wiring for solid connection and continuity; check resistance across both pins (replace sensor if …
Details
125
OUTDOOR_OPEN. Outdoor sensor open - check sensor wiring for solid connection and continuity (repair/replace if bad); check resistance across…
Details
126
RETURN_SHORTED. Return sensor shorted - check resistance across sensor pins (should be between 15 kOhm and 500 ohm; if no resistance present…
Details
127
SUPPLY_SHORTED. Supply sensor 1 shorted - check resistance across left two pins of sensor (15 kOhm to 500 ohm; replace if no resistance) The…
Details
128
SUPPLY2_SHORTED. Supply sensor 2 shorted - check resistance across sensor pins (15 kOhm to 500 ohm; replace if no resistance) The table clas…
Details
129
DHW_SHORTED. DHW sensor shorted - check resistance across both pins of sensor (should be between 15 kOhm and 500 ohm; if no resistance prese…
Details
130
FLUE_SHORTED. Flue sensor shorted - check resistance across both pins of sensor (should be between 15 kOhm and 500 ohm; if no resistance pre…
Details
132
OUTDOOR_SHORTED. Outdoor sensor shorted - check resistance across both pins of sensor (should be between 15 kOhm and 500 ohm; if no resistan…
Details
133
NET_FREQ_ERROR. Net frequency error detected by the watchdog - if error persists, replace control The table classifies it as blocking.…
Details
134
RESET_BUTTON_ERROR. Too many resets in a short time period - allow 1 hour wait period for error to clear; cycle power The table classifies i…
Details
135
PHASE_NEUTRAL_RESERVED_ERROR. Line and neutral of the main voltage power supply input are reversed - check line in power polarity, correct i…
Details
155
WD_CONFIG_ERROR. Watchdog fan configuration setting error - if error persists, replace control The table classifies it as blocking.…
Details
156
FLUE_PRESSURE_ERROR. Blocked flue/condensate switch closed - check for blockages in vent pipe or heat exchanger; check for blockages in cond…
Details
162
FILL_WARNING. Pressure is too low, demand has stopped, but no error needs to be stored at this time The table classifies it as blocking.…
Details
165
VSUPPLY_TOO_LOW. Main supply voltage too low for more than 60 seconds - check supply voltage for values below 108 volts The table classifies…
Details
166
VSUPPLY_TOO_HIGH. Main supply voltage too high for more than 60 seconds - check supply voltage for values above 132 volts The table classifi…
Details
Peerless Cast 92 condensing boilers (HeatNet control, manual C928000 R1)
IGN LOCKOUT
IGN LOCKOUT. Ignition failure: boiler restarts the sequence and will try 3 times, then locks out; display shows IGN LOCKOUT alternating with…
Lockout
FLOW WAIT
FLOW WAIT. Flow switch and other interlocks in the flow switch circuit must prove before the start sequence continues; the display holds FLO…
Details
WATER FLOW SWITCH / WAITING FOR FLOW
WATER FLOW SWITCH or WAITING FOR FLOW. Control does not sense a closed circuit at the FLOW SWITCH input: check that the circulator pump circ…
Details
COMBUSTION AIR DAMPER FAILURE
Combustion air damper failure. Display shows combustion air damper failure: disable the damper in the AUX FUNCTIONS menu if not used; check …
Details
Talk to a boiler technician
Describe what the boiler is doing and get a straight answer about the next step.
On-site service in Greater Vancouver, BC. ROMA lists “Open 7 days” on its site; call to confirm same-day availability.