Main PCB Saunier Duval Isofast F 35 E Ref. 05724800
The main PCB (control board) Saunier Duval Isofast F 35 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, and it may display fault codes 13 or 20. This board is compatible with several boilers in the Isofast range, such as models C 28 E, F 28 E, and C 35 E, among others. It is recommended to replace it when faults in operation are detected or when the mentioned fault codes appear.
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 boiler tries to ignite but immediately locks out with a flame fault.
Cause: The circuit that interprets the ionization signal on the PCB may be giving an incorrect reading.
Check the ionization electrode and its wiring, and clean the contacts before declaring the PCB faulty.
- 02
The boiler turns off by itself several times a day without any fault code appearing.
Cause: It may be due to micro-cuts in the solder joints of the PCB that cause intermittent contact faults.
Check if the fault coincides with vibrations or knocks on the unit; it is an indication of a loose solder joint on the PCB before replacing it.
- 03
The display is frozen or stuck and does not respond to button presses.
Cause: The microcontroller on the PCB may have locked up or the display circuit may have failed.
Disconnect the boiler from the power supply for 30 seconds to force a complete reset before replacing the PCB.
- 04
The production of hot water or heating is only partially working, as if the modulation is not responding properly.
Cause: The PCB manages the modulation of the flame and the fan; if its control circuit fails, the response becomes erratic.
Check that the fault is not related to the gas pressure or the flue gas before attributing it to the PCB.
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
- 1 unit
- 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.
- Silkscreened PCB code
- SYMSI7.0 / 0310144400E5
- Alternative reading of the PCB code
- 0310144400L12
- Fuse
- FUSE T200mA/250V
- Relays
- OMRON G5Q-1A DC24V, 10A 250VAC, lot 2663CQ
- Main microcontroller
- M38039FFP
- Stepper motor driver
- L6219DS
- Optocoupler
- CNY17F-3
- Compatibility reference 05724800
- Main PCB Saunier Duval Isofast/Isomax C28E, C35E, F28E, F35E, C28E NOX
- Two external sources expand the compatibility to the C28E NOX boiler, which is not listed in the compatible boilers of this document; check if your boiler is that model.
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
Is this PCB Ref. 05724800 compatible with the Saunier Duval Isofast F 35 E boiler?
Does the PCB Ref. 05724800 work for the Saunier Duval Isofast C 35 E?
How can I verify if this is the PCB of my Isomax C 28 E boiler?
How many models are compatible with the PCB Ref. 05724800?
What fault codes are documented for this PCB?
What is the reference for this main PCB?
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