Utica Dunkirk E44 Error Code
Difference between supply/ return temperature too high Bad connection Supply/Ret
Source: dmg-240__utdu-dmg-240-iom.pdf
What does Utica Dunkirk E44 mean?
E44 on the Dunkirk DMG-240 indicates the temperature difference between the supply and return water is excessively high — greater than the maximum Delta-T configured in parameter P35. This means heat is being added to the water faster than it is being extracted by the heating system, typically caused by a flow restriction or circulation failure. The boiler shuts down to prevent heat exchanger damage.
Symptoms
- E44 displayed on the DMG-240 control panel — boiler shuts down.
- Supply water temperature is significantly higher than return temperature on the control display.
- Boiler shuts down shortly after start-up when the temperature differential exceeds the threshold.
- Possible thermal noise from the heat exchanger before shutdown.
Common causes
- Circulator pump not delivering adequate flow — impeller blocked or pump at wrong speed setting.
- Closed or partially closed zone valves reducing flow through the heat exchanger.
- Air lock in the heating circuit restricting circulation.
- Supply or return NTC temperature sensor swapped or incorrectly positioned, producing an artificially high differential reading.
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Diagnostic steps
Verify circulation is occurring
With a demand for heat, confirm the supply pipe is warmer than the return and that the pump is audibly and physically running. No temperature difference indicates a pump or flow problem.
Check for closed zone valves or balancing valves
Inspect all zone valves and manual balancing valves in the system. Confirm all valves serving the active zone are fully open and have not been inadvertently closed.
Check sensor wiring and positioning
Confirm the supply sensor is on the supply line and the return sensor is on the return line — not swapped. Verify both sensors are fully inserted into their pipe pockets.
Purge air from the system
Bleed air from all high points in the system and from the auto-air vent on the boiler. Restore system pressure to 15–20 psi and re-test.
Verify parameter P35 setting
Check parameter P35 in the installer menu — this controls the maximum allowable Delta-T. Confirm it is set per the system design specification and has not been incorrectly modified.
When to call a professional
Call a licensed technician if the circulator pump is not running or delivering insufficient flow after basic checks, if the heat exchanger shows signs of overheating or scaling, or if the system piping requires re-balancing. Persistent high Delta-T faults can damage the stainless steel heat exchanger and require professional assessment before returning the boiler to service.
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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