Baxi Roca PCB Laura Plus Ref. 122420390
The Baxi Roca electronic PCB Laura Plus Ref. 122420390 is a fundamental component in the boilers of the Laura Plus range. Its main function is to control the ignition, the modulation of the burner, the pump, and the safety features of the boiler. When this part fails, the boiler may not start, become locked, or exhibit erratic operation, and fault code 27 may be displayed due to a poorly connected modulating valve or a fault in the control board. This PCB is compatible with the Laura Plus 28/28 and Laura Plus 28/28F models, among others. It is recommended to replace it when these symptoms occur or in the event of general malfunction.
Baxi Roca boilers compatible with reference 122420390
PCB with reference 122420390. Two confirmed compatibilities: Laura Plus 28/28 and Laura Plus 28/28F.
Proven compatibility
| Boiler model | Family | Verification |
|---|---|---|
| Baxi Roca Laura Plus 28/28 | Laura Plus 28/28 | Contrasted |
| Baxi Roca Laura Plus 28/28F | Laura Plus 28/28 | 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. 122420390 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 122420390. 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 122420390 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 light up any indicators, it is completely dead.
Cause: The PCB does not distribute power to the control circuits.
Measure if there is power at the input of the PCB and check the fuse with a multimeter before replacing it.
- 02
The boiler starts, tries to ignite the flame, and immediately locks out.
Cause: The PCB does not correctly validate the ignition or flame detection signal and interrupts the cycle for safety.
Check that the ignition and detection electrode is clean and properly connected before attributing the fault to the PCB.
- 03
The domestic hot water comes out at an irregular temperature, rising and falling without reason.
Cause: The PCB does not properly manage the flame modulation according to the flow demand.
Check that the water flow is not reduced by limescale in the heat exchanger before replacing the PCB.
- 04
The display shows a fixed fault code that does not disappear when resetting.
Cause: The PCB maintains the lockout because it detects a persistent anomaly, either real or reading-related.
Write down the exact code and confirm that it does not correspond to a fault in another component before blaming the PCB.
Fault codes for Baxi Roca that this part resolves.
| Code | Fault | Diagnosis and solution |
|---|---|---|
| 27 | Modulating valve poorly connected or fault in the control board. | The PCB (control board) governs the modulating valve; if its output/driver or supervision fails, the boiler interprets the valve as poorly connected and triggers fault code 27. Verify by measuring at the control board connector the power supply and modulation signal to the valve with wiring and coil checked; if it is missing or abnormal, the PCB is faulty. |
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 Baxi Roca PCB 122420390
- Catalogue reference
- 122420390
- Brand
- Baxi Roca
- Type of part
- PCBs (control boards)
- Units in stock
- 0 units
- Status
- Refurbished
- Warranty
- 1 year
- Shipping
- Delivery time shown at checkout
- 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.
- voltage
- 12V
Frequently asked questions about the PCB 122420390
Is this PCB suitable for the Baxi Roca Laura Plus 28/28F?
Spare parts related to Baxi Roca Laura Plus 28/28
