Junkers Euromaxx ZWC28-1MF2A Bosch PCB Ref. 8748300533
The Junkers Euromaxx ZWC28-1MF2A Bosch PCB is the component responsible for controlling the ignition, burner modulation, pump, and safety features of the boiler. When this part fails, the boiler may not start, become locked, or exhibit erratic operation, which can be reflected in the fault code F0: Internal fault/PCB fault. This board is compatible with several boiler models, such as the Euromaxx ZWC 24/28 and the Euromaxx ZWC/ZWB 28/32, among others. It is recommended to replace it if you experience ignition problems or if the boiler shows unusual behaviors.
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Consult via WhatsAppJunkers boilers compatible with reference 8748300533
PCB with reference 8748300533. Six confirmed compatibilities: ZWC24/28-1MFA 23 and ZWC24/28-1MFA 31.
Proven compatibility
| Boiler model | Family | Verification |
|---|---|---|
| Junkers ZWC24/28-1MFA 23 | Euromaxx ZWC 24/28 | Contrasted |
| Junkers ZWC24/28-1MFA 31 | Euromaxx ZWC 24/28 | Contrasted |
| Junkers ZWC24/28-1MFK 23 | Euromaxx ZWC 24/28 | Contrasted |
| Junkers ZWC24/28-1MFK 31 | Euromaxx ZWC 24/28 | Contrasted |
| Junkers ZWC28/32-1MFA 23 | Euromaxx ZWC/ZWB 28/32 | Contrasted |
| Junkers ZWC28/32-1MFA 31 | Euromaxx ZWC/ZWB 28/32 | Contrasted |
Can't see your model or have questions? The printed reference takes precedence. How to check it · Send us a photo via WhatsApp.
How to check if ref. 8748300533 is the part for your boiler
What determines it is not the boiler model, but the reference printed on the part you already have installed.
- Find the reference printed on the installed part and check whether it matches the catalogue reference 8748300533. If it is not visible, do not identify the part from its shape alone.
- Check the full boiler model on its data plate and look for it in the model associations on this page.
- Compare the connections and physical body with the original part before installation.
- If anything is unclear, send us a photo of the marking via WhatsApp before placing your order.
Symptoms and faults that the PCB 8748300533 resolves.
The PCB controls the ignition, modulation, and safety features of the boiler. These are the typical symptoms and what to do:
Common symptoms and faults
- 01
The boiler does not start, it remains in standby forever.
Cause: The PCB manages the entire ignition sequence; if the microcontroller fails, the start command never reaches the burner.
Check that the room thermostat is calling for heat and that the water pressure is correct before ruling out the PCB.
- 02
The display turns off by itself or flickers for no reason.
Cause: The screen is directly dependent on the power supplied by this PCB; a fault in its circuit causes flickering or interruptions.
Turn off the power and plug the boiler back in: if the display resets and fails again shortly after, point to the PCB.
- 03
The controls do not change anything, the temperature remains fixed no matter what happens.
Cause: The microcontroller on the PCB interprets the commands from the controls; if it fails, it stops processing any changes.
Change the temperature of domestic hot water and heating separately: if neither responds, the problem is with the PCB, not with a specific control.
- 04
An error code appears on the display and the boiler locks out.
Cause: The fault codes indicate which part of the system controlled by the PCB has failed, whether it is ignition, flame, or a sensor.
Note the exact code displayed and consult your model's manual to confirm that it points to the electronic control before replacing the PCB.
Fault codes from Junkers that this part resolves.
| Code | Fault | Diagnosis and solution |
|---|---|---|
| F0 | Internal fault/PCB fault. | Internal fault of the PCB (Heatronic/PCB). Check power supply, connectors/plugs, fuses, and RAM/eBus wiring; if it persists, replace the PCB. |
These symptoms can have more than one cause. If your boiler displays a fault code, send it to us via WhatsApp along with a photo of the labeling, and we'll tell you if this is the part.
Data sheet for the Junkers 8748300533 PCB.
- Catalogue reference
- 8748300533
- Brand
- Junkers
- Type of part
- PCBs (control boards)
- Units in stock
- 5 units
- Status
- Refurbished
- Warranty
- 1 year
- Shipping
- 1-2 business days
- Return
- 14 days
Data read on the part and in the manufacturer's documentation
What we have not been able to verify does not appear here.
- Code in the microcontroller (chip)
- 8744901284
- Batch code/date on label
- 0F 14 16 FD 367
- main capacitor
- 1000 µF / 63V
Frequently asked questions about the PCB 8748300533
Does this PCB fit my Junkers Euromaxx ZWC28-1MF2A?
What fault of the Euromaxx ZWC28 does this PCB solve?
How do I check that the code on my PCB matches this reference?
What capacitor is used in the PCB 8748300533 of the Euromaxx?
Spare parts related to Junkers Euromaxx ZWC 24/28
