The control unit manages heater operation by controlling and monitoring the components required during startup, combustion and shutdown.

Part 225201040011 is also formatted as Eberspächer part number 22.5201.04.0011. It is specifically identified for 12V Hydronic D5W, D5WS and D5WSC heater applications.

This control unit replaces earlier Eberspächer part numbers 225201019002 and 225201040000.

Because Eberspächer produced multiple Hydronic D5 configurations, always verify the complete heater identification number, system voltage and existing ECU part number before ordering.

Key Features

• Replacement electronic control unit
• Designed for compatible Hydronic D5 coolant heaters
• 12V electrical configuration
• Compatible with specified D5W heaters
• Compatible with specified D5WS heaters
• Compatible with specified D5WSC heaters
• Controls and monitors heater operation
• Replaces earlier ECU part numbers
• Genuine Eberspächer/ESPAR replacement component

Specifications

• Part Number: 225201040011
• Formatted Eberspächer Number: 22.5201.04.0011
• Historical Part Number: 225201019002
• Historical Part Number: 225201040000
• Product Type: Electronic control unit / ECU
• Voltage: 12V
• Heater Family: Hydronic D5
• Compatible Models: D5W, D5WS and D5WSC
• Primary Function: Heater electronic control and monitoring
• Brand: Eberspächer/ESPAR
• Condition: New replacement part
• Unit of Measure: Each

Compatible Eberspächer/ESPAR Heaters

Part 225201040011 is identified for compatible 12V heaters including:

• Hydronic D5W
• Hydronic D5WS
• Hydronic D5WSC
• 252219050000 D5WSC 12V
• 252217050000 D5WS 12V
• 252228050000 D5WS 12V
• 252229050000 D5WS
• 252390050000 D5WSC 12V
• 252386050000 D5WS 12V

This is a 12V control unit and should not be substituted for a 24V ECU.

Common Service Applications

The control unit may require replacement when:

• Electrical diagnosis identifies an ECU failure
• The existing ECU is physically damaged
• The control-unit wiring or connections are damaged
• A compatible Hydronic D5 heater requires replacement of the original controller
• Replacing an earlier 225201019002 control unit
• Replacing an earlier 225201040000 control unit
• Completing a comprehensive Hydronic D5 repair

A heater fault code or failure to operate does not automatically confirm ECU failure. The heater and associated components should be properly diagnosed before replacing the control unit.

Important Installation Notes

• Confirm that the heater operates on 12 volts.
• Confirm the complete heater identification number.
• Compare the existing control-unit number before ordering.
• Do not substitute a 24V control unit.
• Disconnect electrical power before servicing the heater.
• Inspect the heater wiring and electrical connectors.
• Inspect connections for corrosion or physical damage.
• Correct faults elsewhere in the heater before installing a replacement ECU.
• Install the control unit in the correct position.
• Secure all electrical connections before applying power.
• Test heater operation after completing the repair.

Related Products

• 201819991600 – Eberspächer/ESPAR Hydronic D4WSC/D5WSC 12V Combustion-Air Blower
• 252219250000 – Eberspächer/ESPAR Hydronic D4WSC/D5WSC 12V Water Pump
• 252106011300 – Eberspächer/ESPAR Hydronic D4WSC/D5WSC 12V Glow Pin
• 251920370000 – Eberspächer/ESPAR Hydronic D4W/D5W Flame Sensor
• 252216100000 – Eberspächer/ESPAR Hydronic D4W/D5W Burner
• 201820990001 – Eberspächer/ESPAR Hydronic D4/D5 Burner and Blower Gasket Set
• 252121990113 – Eberspächer/ESPAR Hydronic D4W/D5W Glow-Pin Lining