Main PCB Saunier Duval Isomax C 28 E Ref. 05724800
The main PCB (control board) Saunier Duval Isomax C 28 E is the component that controls the ignition, the modulation of the burner, the pump, and the safety features of the boiler. When it fails, the boiler may not start, lock out, or exhibit erratic behavior. The user may notice this through the fault codes 13: Main printed circuit failure and 20: Communication defect/incompatible interface with the main board. This board is compatible with several models from the Isofast and Isomax ranges, among others. It should be replaced when these symptoms or fault codes are experienced.
VAT included
Consult via WhatsAppSaunier Duval boilers compatible with reference 05724800
PCB with reference 05724800. Eight confirmed compatibilities: C 28 E and C 28 E NOx.
Proven compatibility
| Boiler model | Family | Verification |
|---|---|---|
| Saunier Duval C 28 E | Isofast | Contrasted |
| Saunier Duval C 28 E NOx | Isofast | Contrasted |
| Saunier Duval F 28 E | Isofast | Contrasted |
| Saunier Duval C 35 E | Isofast | Contrasted |
| Saunier Duval F 35 E | Isofast | Contrasted |
| Saunier Duval C 24 E V | Isofast | Contrasted |
| Saunier Duval C 28 E | Isomax | Contrasted |
| Saunier Duval F 28 E | Isomax | 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. 05724800 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 05724800. 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 05724800 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 remote control or the thermostat does not make the boiler operate.
Cause: The microcontroller on the PCB manages the ignition commands; if it fails, the boiler does not respond even if it receives the demand signal.
Force the manual ignition on the boiler, without using the thermostat; if it still does not respond, the problem is before the control.
- 02
The boiler shuts down suddenly, without prior warning.
Cause: The 125 mAT fuse cuts off the power to the PCB when it detects an overload.
Check the fuse with a multimeter before replacing the PCB; if it is blown, check if any wire or connector is damaged or short-circuited.
- 03
The boiler turns on but loses communication with the display or the remote control.
Cause: The transformer marked Saunier Duval provides the operating voltage to the microcontroller and the communication line.
With the boiler turned on, check if the display flickers or turns off at the same time communication fails; this indicates a power supply issue, not just a wiring problem.
- 04
The boiler works well for a few days and then stops starting for no apparent reason.
Cause: An intermittent fault in the microcontroller or its solder joints can cause the PCB to stop executing the ignition sequence randomly.
Note the time and conditions (cold, restart after power cut, etc.) each time it fails; a repeated pattern helps to identify whether the fault is with the PCB or an external issue.
Fault codes from Saunier Duval that this spare part resolves.
| Code | Fault | Diagnosis and solution |
|---|---|---|
| 13 | Main printed circuit board fault. | The main PCB is faulty. Check auxiliary voltages (5/12 VDC) and connectors of the PCB; if the power supply and wiring/UI are correct and the board does not deliver voltages or shows damage/continuous reset, replace the PCB. |
| 20 | Communication fault/incompatible interface with the main PCB. | The main PCB is incompatible or there is a communication failure with the user interface (coding/DSN or e‑Bus). Verify product code and compatibility UI↔PCB; if the fault persists with the correct UI, the cause is 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 Saunier Duval 05724800 PCB.
- Catalogue reference
- 05724800
- Brand
- Saunier Duval
- Type of part
- PCBs (control boards)
- Units in stock
- 2 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.
- Transformer
- CECLA 47615A, marked Saunier Duval, code SF 612203, in accordance with EN 60742
- Fuse
- 125 mAT
- Silkscreened code on the PCB
- 105302 H / 0033 / EPIQ
Manuals and technical documentation
Official documentation of the boiler, useful for locating the part and cross-referencing the fault codes.
- Saunier Duval F 28 E Manual (PDF)Document © Saunier Duval, provided as a technical reference.
Frequently asked questions about the PCB 05724800
Does the code 105302 H that I see on my PCB correspond to the Ref. 05724800 of the Isomax C 28 E?
Does this PCB Ref. 05724800 from the Isomax C 28 E also work for the Isofast F 35 E?
What transformer does this PCB use and which standard does it comply with?
Which fuse should I check on this PCB of the Isomax C 28 E?
Spare parts related to Saunier Duval Isofast
