Utica Dunkirk E41 Error Code
No water temperature change during deaeration/ air purge Bad connection Supply/R
Source: dmg-240__utdu-dmg-240-iom.pdf
What does Utica Dunkirk E41 mean?
E41 on the Dunkirk DMG-240 means no water temperature change was detected during the deaeration and air-purge cycle. At first start-up, the boiler runs the circulator to purge air from the system. If the supply and return sensors do not detect any temperature differential during this cycle, the control concludes that water is not circulating and logs E41.
Symptoms
- E41 displayed on the DMG-240 control panel during the initial deaeration/air-purge sequence.
- Pump runs during the deaeration cycle but supply and return temperatures do not diverge.
- Boiler does not advance past the air-purge phase to burner ignition.
- System may have audible air sounds or gurgling indicating air lock.
Common causes
- Air lock in the hydronic system preventing water circulation during deaeration.
- Wiring connection to the supply or return temperature sensor is loose or disconnected.
- Supply or return NTC temperature sensor is damaged or failed.
- Circulator pump is not running due to a wiring fault or seized impeller.
Ask the AskWhiz AI about Utica Dunkirk E41
AskWhiz
online
Diagnostic steps
Verify the pump is running
Listen and feel for pump operation during the deaeration cycle. If the pump is silent and not vibrating, check pump wiring connections and verify voltage at the pump terminals.
Check temperature sensor wiring connections
Inspect the wiring plugs on both the supply and return temperature sensors. Firmly reseat any loose connectors and check for damaged insulation or bent pins.
Purge air from the system manually
Use the auto-air vent and system bleed points to remove air from the hydronic circuit. Confirm the system is filled to the correct pressure (15–30 psi) before re-running deaeration.
Test temperature sensor resistance
Disconnect each NTC sensor and measure resistance at room temperature. Compare the reading to the published resistance-temperature chart in the IOM. Replace any sensor with an out-of-range reading.
Re-run the deaeration function
After correcting any wiring, sensor, or air-purge issues, initiate the deaeration function again from the installer menu and verify the supply and return temperatures begin to converge.
When to call a professional
Call a licensed technician if the pump fails to run after wiring inspection, if both sensors read incorrectly, or if the system cannot be purged of air due to a complex loop configuration. Boiler commissioning and the deaeration procedure on a new installation should be completed by a qualified technician to ensure safe first-start operation.
Stop searching through PDFs. Our AI assistant on WhatsApp is trained on official Utica Dunkirk documentation and can diagnose this fault code and guide you through the repair in minutes.
Free tier — 10 messages/month, no credit card.
Other Utica Dunkirk Error Codes
,E28,E40,E50,E160,E321,and E431 -Indicate possible faulty components. 53 - Indic
, 78 and 92 - Indicates possible wrong calibration, a new calibration is needed.
,E135 - Indicate the gas supply has been interrupted, ignition has failed or fla
,E 133, E 134,E 135, E 09,E 15,E 128 and E 384 - are displayed it is possible to
Gas Valve Connection Cable 日 10 External Probe Fault 12 Water Flow Switch Open 1
Water Refill Enabled E 19 Max Time Of Water Refill 20 Central Heating Flow NTC F
Flue NTC Fault E40 Central Heating Return NTC Fault Hot Water NTC Fault (tank ve
PCB to be set by the "Calibration Function" E 171 Fan parameter Out of range in
87 Communication error E92 Combustion test alarm during auto-setting E 1 109 Pre
E11 between the supply and return temperatures too Sensor not/poorly connected N
Temperature of heat exchanger is above the normal range (high- limit thermostat
5 burner start-up failures that the air inlet and exhaust flue are not blocked C
Sources: dunkirk.com