Dunkirk Boilers · Error codes
Dunkirk 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.
Dunkirk Royal CO/CH combi and heating boilers (fault codes, residential IOM E93.1907.035.915.C)
0
EEPROM Read Error. Internal software error Cause: wrongly programmed BCU or PB Solving: reset BCU or replace BCU and / or PB display unit Th…
Lockout
1
Ignition Error. Five unsuccessful ignition attempts in a row Cause: no gas, wrongly adjusted gas valve Solving: check gas supply and ad- jus…
Lockout
2
GasValve Relay Error. Failure detected in the gas valve relay Cause: short circuit in coil of the gas valve, water on wiring or gas valve So…
Lockout
3
Safety Relay Error. Failure detected in safety relay Cause: safety relay is not working correctly Solving: reset BCU or replace BCU The tabl…
Lockout
4
Blocking Too Long Error. Control had a blocking error more than 20 hours Cause: blocking code active more than 20 hours Solving: reset and c…
Lockout
5
Fan Not Running. Fan is not running for more than 60 seconds Cause: electrical wiring is not correctly connected, or fan malfunctioning Solv…
Lockout
6
Fan Too Slow. Fan runs too slow for more than 60 seconds Cause: electrical wiring is not correctly connected, or fan malfunctioning Solving:…
Lockout
7
Fan Too Fast. Fan runs too fast for more than 60 seconds Cause: electrical wiring is not correctly connected, or fan malfunctioning Solving:…
Lockout
8
RAM Error. Internal software error Cause: wrongly programmed BCU or PB Solving: reset BCU or replace BCU and / or PB display unit The table …
Lockout
9
Wrong EEPROM Signature. Contents of E2prom is not up to date Cause: outdated E2prom Solving: reset BCU or replace BCU The table classifies i…
Lockout
10
EEPROM Error. Wrong safety parameters in E2prom Cause: wrongly programmed BCU or PB Solving: reset BCU or replace BCU The table classifies i…
Lockout
11
State Error. Internal software error Cause: wrongly programmed BCU or PB Solving: reset BCU or replace BCU The table classifies it as lockou…
Lockout
12
ROM Error. Internal software error Cause: wrongly programmed BCU or PB Solving: reset BCU or replace BCU The table classifies it as lockout.…
Lockout
15
Max. Thermostat Lock Error. The external overheat protection is enabled or the T_Supply sensor measures a temp. of over Prot_Overheat_Temp -…
Lockout
16
Max. Flue Lock Error. Flue temperature exceeded the maximum flue temperature Cause: there is no water in the heat exchanger or flue gas sens…
Lockout
17
Stack Error. Internal software error Cause: wrongly programmed BCU or PB Solving: reset BCU or replace BCU and or PB display unit The table …
Lockout
18
Instruction Error. Internal software error Cause: wrongly programmed BCU or PB Solving: reset BCU or replace BCU and or PB display unit The …
Lockout
19
Ion Check Failed. Internal software error Cause: wrongly programmed BCU or PB Solving: reset BCU or replace BCU and or PB display unit The t…
Lockout
20
Flame Out Too Late Error. Flame still present 10 sec. after closing the gas valve Cause: wrong earthing of BCU and boiler Solving: check ear…
Lockout
21
Flame Before Ignition. Flame is detected before ignition Cause: wrong earthing of BCU and boiler Solving: check earthing of BCU and boiler T…
Lockout
22
Too Many Flame Failures. Three times flame lost during 1 demand Cause: bad gas supply or CO2 level is not correct or bad ignition rod Solvin…
Lockout
23
Corrupted Error Number. Error code RAM byte was corrupted to an unknown error code. Cause: wrongly programmed BCU or PB Solving: reset BCU o…
Lockout
27
Filling Too Much. Too many automated filling attempts in a short time period Cause: if output is programmed as filing valve and there are to…
Lockout
28
Fill Time Error. Filling takes too long Cause: if output is programmed as filling valve and filling takes more than 10 minutes Solving: chec…
Lockout
29
PSM Error. Internal software error Cause: wrongly programmed BCU or PB Solving: reset BCU or replace BCU and or display unit The table class…
Lockout
30
Register Error. Internal software error Cause: wrongly programmed BCU or PB Solving: reset BCU or replace BCU and or display unit The table …
Lockout
32
T. Exchange Diff Error. The 2 exchange sensors deviate too much for more than 60 seconds Cause: there is not enough water flow through the h…
Lockout
33
LWCO/Air intake block. Low water cut off 1 error Cause: there is no water in the heat exchanger or not electrically connected Solving: check…
Lockout
34
LWCO 2 Error. Low water cut off 2 error Cause: there is no water in the heat exchanger or not electrically connected Solving: check if there…
Lockout
38
Flue pressure Locking. More than 3 flue pressure switch errors have occurred in 24 hrs. Cause: Syphon is clogged or vent is blocked Solving:…
Lockout
100
WD Error Ram. Internal software error Cause: wrongly programmed BCU or PB Solving: reset BCU or replace BCU and / or PB display unit The tab…
Details
101
WD Error Rom. Internal software error Cause: wrongly programmed BCU or PB Solving: reset BCU or replace BCU and / or PB display unit The tab…
Details
105
High Temp Error. T_Supply sensor measures over stay_Burning_Temp for a period of Max_Value_Period. Cause: not enough waterflow causes overhe…
Details
106
Refhi Too Hi Error. Internal hardware error Cause: wrongly programmed BCU or PB Solving: reset BCU or replace BCU and / or PB display unit T…
Details
107
Refhi Too Lo Error. Internal hardware error Cause: wrongly programmed BCU or PB Solving: reset BCU or replace BCU and / or PB display unit T…
Details
108
Reflo Too Hi Error. Internal hardware error Cause: wrongly programmed BCU or PB Solving: reset BCU or replace BCU and / or PB display unit T…
Details
109
Reflo Too Lo Error. Internal hardware error Cause: wrongly programmed BCU or PB Solving: reset BCU or replace BCU and / or PB display unit T…
Details
110
Refhi2 Too Hi Error. Internal hardware error Cause: wrongly programmed BCU or PB Solving: reset BCU or replace BCU and / or PB display unit …
Details
111
Refhi2 Too Lo Error. Internal hardware error Cause: wrongly programmed BCU or PB Solving: reset BCU or replace BCU and / or PB display unit …
Details
112
Reflo2 Too Hi Error. Internal hardware error Cause: wrongly programmed BCU or PB Solving: reset BCU or replace BCU and / or PB display unit …
Details
113
Reflo2 Too Lo Error. Internal hardware error Cause: wrongly programmed BCU or PB Solving: reset BCU or replace BCU and / or PB display unit …
Details
114
False Flame. Flame is detected in a state in which no flame is allowed to be seen Cause: wrong earthing of BCU and boiler Solving: check ear…
Lockout
116
Low Water Pressure Sensor. Low water pressure, occurs when the pressure drops below drops below 11.6 psi. Cause: not enough water pressure S…
Details
118
WD Communication Error. Watchdog communication error Cause: wrong programmed BCU or PB Solving: reset BCU or replace BCU and / or PB display…
Details
119
T Return Open. Return sensor open Cause: malfunctioning return sensor or not connected Solving: check connection to BCU or check resistance …
Details
120
T Supply Open. Supply sensor open Cause: malfunctioning supply sensor or not connected Solving: check connection to BCU or check resistance …
Details
122
T DHW Open. DHW sensor open Cause: malfunctioning DHW sensor or not connected Solving: check connection to BCU or check resistance NTC senso…
Details
123
T Flue Open. Flue sensor open Cause: malfunctioning or not connected flue sensor Solving: check connection to BCU or check resistance NTC se…
Details
125
T Outdoor Open. Outdoor sensor open Cause: malfunctioning or not connected outdoor sensor or wrong CH- mode programmed Solving: check connec…
Details
126
T Return Shorted. Return sensor shorted Cause: malfunctioning return sensor or short circuiting Solving: check connection to BCU or check re…
Details
127
T Supply Shorted. Supply sensor shorted Cause: malfunctioning supply sensor or short circuiting Solving: check connection to BCU or check re…
Details
129
T DHW Shorted. DHW sensor shorted Cause: malfunctioning DHW sensor or short circuiting Solving: check connection to BCU or check resistance …
Details
130
T Flue Shorted. Flue sensor shorted Cause: malfunctioning flue sensor or short circuiting Solving: check connection to BCU or check resistan…
Details
132
T Outdoor Shorted. Outdoor sensor shorted Cause: malfunctioning outdoor sensor or short circuiting Solving: check connection to BCU or check…
Details
134
Reset Button Error. Too many resets in a short time period Cause: reset too many times by user or installer Solving: wait or disconnect and …
Details
136
T_Exchange Block Error. Exchange temperature exceeded 194 ºF (90 ºC). Cause: water temperature is above 194 ºF (90 ºC). Solving: check circu…
Details
155
WD Config Error. Watchdog fan confi- guration setting error Cause: wrongly programmed BCU or PB Solving: reset BCU or replace BCU and / or P…
Details
156
Flue Pressure Error. Flue pressure switch is closed Cause: Syphon clogged or vent blocked Solving: Clean syphon. Check vent. The table class…
Details
164
Ex. Low Flow Protection. Flow is too low, demand needs to be stopped with fan at ignition speed*, but no error needed to be stored at this t…
Lockout
168
Flue Temperature too high. Flue sensor measures above 203°F Cause: Dirty combustion chamber Solving: Clean the combustion chamber, especiall…
Details
169
ADC Unstable. ADC measurements detected too many unstable measurements Cause: Defect sensor or unstable 0-10V input signal Solving: Check se…
Details
200
Comm. Lost with module. Cascade System: Managing cascade control lost communication with one of the depending. Cause: connection between cas…
Details
202
App. Selection Error. Unknown appliance model selected Cause: wrongly programmed parameters Solving: replace BCU The table classifies it as …
Details
203
Comm. Lost with boiler. Dual Cascade System: Managing cascade control lost communication with one of the depending. Cause: connection betwee…
Details
204
T Outdoor Wrong. T_Outdoor sensor measures open or shorted Cause: malfunctioning outdoor sensor or not connected or wrong CH-mode programmed…
Details
205
T System Wrong. T_System sensor measures open or shorted Cause: malfunctioning system sensor or not connected Solving: check connection to B…
Details
206
T Cascade Wrong. T_Cascade sensor measures open or shorted Cause: malfunctioning cascade sensor or not connected Solving: check connection t…
Details
207
Heat-Exchanger protection active. The heat-exchanger protection function is actively blocking the burn demand The table classifies it as war…
Details
Dunkirk DMG-240/380 condensing boilers (fault codes, IOM 240011656/240011664)
E00
Storage unit PSU parameter not found. Bad connection - check the wiring The table classifies it as error.…
Details
E01
The safety parameters are incorrect. Bad connection, PSU defective - check the wiring, replace PSU The table classifies it as error.…
Details
E02
Supply temperature sensor short circuited. Bad connection, sensor fault, sensor not/poorly connected - check wiring, check sensors operate c…
Details
E03
Supply temperature sensor open circuit. Bad connection, sensor fault, sensor not/poorly connected - check wiring, check sensors operate corr…
Details
E04
Temperature of heat exchanger too low. Bad connection, sensor fault, sensor not/poorly connected - check wiring, replace sensor if necessary…
Details
E05
Heat exchanger temperature too high. No circulation - check sensors operate correctly and are fitted correctly, check cleanliness of heat ex…
Details
E06
Return temperature sensor short circuited. Bad connection, sensor fault, sensor not/poorly connected - check wiring, check sensor fitted cor…
Details
E07
Return temperature sensor open circuit. Bad connection, sensor fault, sensor not/poorly connected - check wiring, check sensors operating co…
Details
E08
Return temperature too low. Bad connection, sensor fault, no circulation - check wiring, replace sensor if necessary, purge air from heating…
Details
E09
Return temperature too high. Bad connection, sensor fault, no circulation - check wiring, replace sensor if necessary, purge air from heatin…
Details
E10
Temperature difference between the supply and return temperatures too great. Sensor fault, sensor not/poorly connected, no circulation - rep…
Details
E11
Temperature difference between the supply and return temperatures too great. Sensor fault, sensor not/poorly connected, no circulation - rep…
Details
E12
Temperature of heat exchanger above the normal range (high-limit thermostat Safety Thermostat). Bad connection, sensor fault, sensor not/poo…
Details
E14
5 burner start-up failures. No ignition - check spark generator wiring, ionization/ignition electrode, burner condition, grounding, defectiv…
Lockout
E16
False flame signal. Ionization current present when there should not be a flame, ignition transformer defective, gas valve defective, burner…
Lockout
E17
Problem on SU PCB. Bad connection, defective SU PCB - check wiring, inspect SU PCB and replace if needed The table classifies it as error.…
Details
E34
Fan fault. Bad connection, fan defective - check wiring, replace fan if necessary, check for adequate draw on the flue connection (CHART 7) …
Details
E35
Supply and return reversed. Bad connection, sensor fault, sensor not/poorly connected, water circulation direction reversed - check wiring, …
Details
E36
Flame loss. No ionization current - purge gas supply to remove air, check gas valve fully open and supply pressure, check operation and sett…
Lockout
E37
Communication error with SU PCB. Bad connection - check whether SU PCB has been correctly fitted in connector on PCU PCB The table classifie…
Details
E38
Communication error with SCU PCB. Bad connection, defective SCU PCB - check the wiring, replace SCU PCB The table classifies it as error.…
Details
E39
Shutdown input in locked-out mode. Bad connection, external problem, parameter incorrectly set - check wiring, find external problem, check …
Details
E40
HRU unit test error. Bad connection, external problem, parameter incorrectly set - check wiring, find external problem, check parameters (CH…
Details
E41
No water temperature change during deaeration/air purge. Bad connection, supply/return sensor damaged, no water circulation - check sensor c…
Details
E42
Low water cutoff disconnected or water pressure too low. Bad connection, water pressure low - check wiring, refill the system, check for lea…
Details
E43
No water temperature change during boiler operation (burner on). Bad connection, supply/return sensor damaged, no water circulation - check …
Details
E44
Difference between supply/return temperature too high. Bad connection, supply/return sensor damaged, no water circulation - check sensor con…
Details
Su:0
Parameter error. Parameter error on the PSU PCB - reset df and dU, restore parameters The table classifies it as shutdown.…
Details
Su:1
Maximum supply temperature exceeded. Non-existent or insufficient circulation / sensor error - check circulation (direction, pump, valves), …
Details
Su:2
Maximum increase of the supply temperature exceeded. Non-existent or insufficient water circulation / sensor error - check circulation, wate…
Details
Su:7
Max difference between T. supply/return exceeded. Non-existent or insufficient circulation / sensor error - check circulation, water pressur…
Details
Su:8
No release signal. External cause, parameter error, bad connection - correct external cause, check parameters, check wiring The table classi…
Details
Su:9
Line and neutral of power supply are mixed up (if P43=1). Power supply incorrectly wired, floating or 2 phase network - line and neutral mix…
Details
Su:10
Shutdown input is open. External cause, parameter error, bad connection - correct external cause, check parameters, check wiring The table c…
Details
Su:11
Shutdown input active or frost protection active. External cause, parameter error, bad connection - correct external cause, check parameters…
Details
Su:13
Communication error with the SCU PCB. Bad connection with BUS, SCU PCB not installed in boiler - check wiring, carry out automatic detection…
Details
Su:15
Gas pressure too low. Non-existent or insufficient gas pressure, incorrect setting of the Gps gas pressure switch on SCU PCB - check gas val…
Details
Su:16
Configuration fault or SU PCB not recognized. Wrong SU PCB for this boiler - replace the SU PCB (not stored in fault memory) The table class…
Details
Su:17
Configuration fault or default parameter table incorrect. Parameter dF-dU error on the PSU PCB - reset df and dU, restore parameters (not st…
Details
Su:18
Configuration fault or PSU PCB not recognized. Wrong PSU PCB for this boiler - replace the PSU PCB (not stored in fault memory) The table cl…
Details
Su:19
Configuration fault or parameters df-du unknown. Reset df and dU, restore parameters (not stored in fault memory) The table classifies it as…
Details
Su:20
Identification running. No action required (not stored in fault memory) The table classifies it as shutdown.…
Details
Su:21
Communication error with SU PCB. Bad connection - check whether SU PCB has been correctly fitted in the connector on SU PCB The table classi…
Details
Su:22
No flame during operation. No ionization current - purge gas supply to remove air, check gas valve fully open, check supply pressure, check …
Lockout
Su:25
Internal error on the SU-PCB. Replace the SU PCB (not stored in fault memory) The table classifies it as shutdown.…
Details
Su:29
tFG sensor above maximum setpoint. Non-existent or insufficient water circulation / sensor error - replace flue high limit, check circulatio…
Details
Su:30
No tFG sensor connected / shorted - boiler stop. Flue high limit disconnected / sensor error - replace flue high limit The table classifies …
Details
Su:33
After 5 times tF>tF Max: controlled stop. Non-existent or insufficient circulation / sensor error - replace supply sensor, check circulation…
Details
Su:34
After 5 times tFG>tfmax: controlled stop. Non-existent or insufficient circulation / sensor error - replace flue high limit, check circulati…
Details
Su:35
Insufficient gradient on T1(supply) or T2(return) after burner starts. Non-existent or insufficient circulation / sensor error - check circu…
Details
Dunkirk DCC/DCB wall condensing boilers (fault codes, manual MGC-2209 Rev A)
09
Gas valve connection fault. Check cable PCB/gas valve and gas valve plug The table classifies it as error.…
Details
10
Outdoor sensor fault. Check sensor and cable The table classifies it as error.…
Details
15
Gas valve command fault. Verify all cables. Replace PCB. The table classifies it as error.…
Details
20
Central Heating NTC sensor fault. Check sensor and cable The table classifies it as error.…
Details
28
Flue NTC heat exchanger sensor fault. Check sensor and cable The table classifies it as error.…
Details
40
Return NTC sensor fault. Check sensor and cable The table classifies it as error.…
Details
50
Domestic Hot Water NTC sensor fault. Check sensor and cable The table classifies it as error.…
Details
53
Obstruction in flue pipe, Recirculation, Out of Calibration, Poor gas quality. Check for obstruction in flue pipe. Check gas pressure, check…
Details
55
PCB not programmed. Follow instructions provided with control board replacement kit, call technical service for assistance. The table classi…
Details
E72/E92
Combustion test alarm during commissioning / calibration. Check flame sensor, check for obstruction in flue pipe, check for recirculation, c…
Details
78
Minimum gas valve IMOD current. Check gas supply pressure. Check the correct position and integrity of the sensing electrode. Check and clea…
Lockout
79
Maximum gas valve IMOD current. Auto calibrate, manual calibrate if necessary. Replace components if all else fails. The table classifies it…
Details
E83
OT Communication Failure. Check OT connection, remove power, reconnect OT connections, if problem persists replace service key. The table cl…
Details
84-85
Communication problem between boiler board and control unit. Probable short circuit on wiring. Check cable between control unit and boiler. …
Details
86-87
Communication problem between boiler board and control unit. Probable short circuit on wiring. Check cable between control unit and boiler. …
Details
109
Pre-circulation alarm (temporary fault). Check correct circulation of water and pump. Check supply and return wiring is correct. The table c…
Details
110
Safety thermostat tripped due to over temperature (pump probably blocked or air in heating circuit). Check safety thermostat and cable; chec…
Details
117
Hydraulic pressure too high. Relieve pressure via relief valve or drain. Ensure water feed is operating correctly. The table classifies it a…
Details
118
Hydraulic pressure too low. Refill heating system by opening cold water tap. The table classifies it as error.…
Details
125
No circulation of water (control performed via temperature sensor). Check correct circulation of water and pump. Check correct connection of…
Details
128
Loss of flame 8 consecutive times after flame proving stage. Check sensing electrode and cable, flue recirculation, electrical continuity be…
Details
130
NTC flue sensor tripped due to over temperature. Check thermostat, correct circulation of water and pump. Check status of primary exchanger.…
Details
131
Thermo fuse tripped due to over temperature or wire harness disconnected from thermo fuse, off the board, or wire harness may be cut. Check …
Details
133
Ignition failure. Check correct operation of condensate trap. Check sensing electrode, spark electrode and cable. Check flue recirculation, …
Lockout
134
Gas supply valve blocked. Check gas pressure, sensing electrode, spark electrode and cable, replace PCB if it necessary. The table classifie…
Lockout
135
Internal error. Verify all cables. Replace PCB. The table classifies it as error.…
Details
160
Fan fault. Check fan and cable. The table classifies it as error.…
Details
162/317
Incorrect power supply frequency. Incorrect power supply frequency. The table classifies it as error.…
Details
169
Flue pressure switch (contact open). Check pressure switch and cable. Check obstruction on flue pipe. The table classifies it as error.…
Details
164/384
Fault flame (parasitic flame). Check correct operation of T. gas valve. The table classifies it as error.…
Details
165/385
Input voltage too low. Check power supply. The table classifies it as error.…
Details
E178
Low return water temperature / anti-freeze function active. Check the return water sensor, check the circulator, check the correct circulati…
Details
E62
Anti-wind activation with increase of the minimum fan speed. Check the position of the terminal of the flue duct. The table classifies it as…
Details
E63/E65
Combustion level out of range. Check flue recirculation and combustion levels. The table classifies it as error.…
Details
E65
Maximum value of the speed reached / correction of the flame signal. Check flue recirculation on the flue duct. The table classifies it as e…
Lockout
E67
Anti-wind activation at maximum power. Check the position of the terminal of the flue duct. The table classifies it as error.…
Details
E69
Combustion level out of range. Check flue recirculation and the combustion levels. The table classifies it as error.…
Details
E70
Flame signal problem/micro interruption of the flame signal. Check cable and integrity of the sensing electrode, verify the continuity betwe…
Lockout
E73
Combustion adjustment / modified during operation. Review and monitor other codes such as E53 and E92. The table classifies it as error.…
Details
Dunkirk XEB Series 4 gas-fired steam boilers (integrated boiler control error codes, I&O 240013870 Rev A)
2
Pressure switch failed to open (stuck closed). The control relies on the pressure switch to verify the inducer motor is running and the vent…
Details
4
Flame current lower then threshold. The control requires a signal of at least 1 uA to verify flame is present and the signal is too low; che…
Lockout
6
Flame sensed out of normal sequence. The control circuit is sensing flame rectification when there should be none; check the gas valve and t…
Details
18
Electronic failure. The control believes it is defective; try a reset by cycling power or pushing any key, check wiring to the pilot and mai…
Lockout
23
Flame sensed during Pre-purge. The pilot is being sensed too soon in the ignition sequence; check the gas valve for zero manifold pressure w…
Lockout
24
Flame sensed during Post-purge. The pilot is being sensed too late in the shutdown sequence; check the gas valve for zero manifold pressure …
Details
29
Pressure switch failed to close (switch stuck open). The pressure switch must close at the start of the heat cycle but did not; check the pr…
Details
32
Temperature sensor failure. The temperature sensor is not providing an expected reading; check the sensor is plugged into the control board …
Details
57
Flame rod shorted to burner ground. The control did not detect a voltage difference between the flame sense wire and ground; check the flame…
Lockout
58
AC line frequency error. The AC frequency is incorrect or noisy; verify no electric or electronic devices are generating electromagnetic int…
Details
59
Line voltage error. The line voltage (or possibly the thermostat) is either too high or too low; the source problem is likely in the electri…
Details
60
Thermostat input higher then threshold. The thermostat input is higher than the threshold because certain types of thermostat may not be com…
Details
61
Line voltage unstable. The line voltage is unstable, possibly because too many heavy loads are switching on and off; check the branch circui…
Details
62
Soft Lockout-Max retries exceeded. The control sensed consecutive instances of no flame signal while trying to light the pilot; check the co…
Lockout
63
Soft Lockout- Max recycles exceeded. The control sensed consecutive instances of loss of pilot flame signal after the main burners lit; chec…
Lockout
64
Soft Lockout- Internal Failure. The control is sensing something wrong with the electrical circuitry; check all wiring against the wiring di…
Lockout
65
Hard Lockout- Temperature above limit. The control sensed a water temperature too high for safe boiler operation; check that water is circul…
Lockout
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.