
Saunier Duval ISOFAST/ISOMAX PCB (control board)
In the Saunier Duval ISOFAST and ISOMAX boilers, the Saunier Duval ISOFAST/ISOMAX PCB, reference S10400, manufactured by Myrra, is installed. This control board is responsible for managing the ignition, burner modulation, pump, and safety features of the boiler. If it fails, you will notice that the boiler does not start, locks out, or operates erratically, potentially displaying faults such as 13 or 20. It is compatible with models such as C 24 E V1, C 28 E1, and F 28 E2, among others. It should be replaced when these symptoms are present or when any visible damage is detected.
VAT included
Consult via WhatsAppChaffoteaux boilers compatible with reference S1019000
PCB with reference S1019000. Eight confirmed compatibilities: C 24 E V1 and C 28 E1.
Proven compatibility
| Boiler model | Family | Verification |
|---|---|---|
| Chaffoteaux C 24 E V1 | ISOFAST | Contrasted |
| Chaffoteaux C 28 E1 | ISOFAST | Contrasted |
| Chaffoteaux C 28 E1 NOx | ISOFAST | Contrasted |
| Chaffoteaux C 35 E1 | ISOFAST | Contrasted |
| Chaffoteaux F 28 E1 | ISOFAST | Contrasted |
| Chaffoteaux F 35 E1 | ISOFAST | Contrasted |
| Chaffoteaux C 28 E2 | ISOMAX | Contrasted |
| Chaffoteaux F 28 E2 | 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. S1019000 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 S1019000. 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 S1019000 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 ignite and the display is off.
Cause: The transformer or the power supply stage of the PCB is not supplying current to the control circuits.
Measure the output of the transformer on the PCB with a multimeter before replacing it.
- 02
The display lights up but the boiler does not ignite.
Cause: The PCB starts up but does not process the demand or activate the fan or the gas valve.
Check for a real demand for heating or hot water (tap open, thermostat calling) before ruling out the PCB.
- 03
A different fault code appears every time you reset the boiler.
Cause: The PCB has an unstable internal fault that manifests randomly at each startup.
Note the codes that appear; if they change without any detectable real fault, point to the PCB.
- 04
The boiler loses its programming or settings when it completely shuts down.
Cause: The memory of the PCB does not retain data when there is a power outage, a typical symptom of a fault at that stage.
Check if the PCB has a backup battery and if it is depleted before replacing the entire board.
Fault codes Chaffoteaux that this part resolves
| Code | Fault | Diagnosis and solution |
|---|---|---|
| 13 | Main printed circuit board fault. | The main PCB (S1019000) does not pass the internal self-diagnosis; this is usually due to an electronics/EEPROM fault or the PCB not generating its internal voltages. Check the 230 V input, fuse, and low voltages (5/15/24 V) on the PCB; if these are correct and the wiring is OK, replace the PCB. |
| 20 | Communication fault between the user interface and the main PCB. | Communication channel/ebus fault on the main board, incompatibility between interface and PCB or defective connection/harness. Check the interface power supply from the board, connectors/harness and test with a known interface; if it persists, 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 Chaffoteaux S1019000 PCB.
- Catalogue reference
- S1019000
- Brand
- Chaffoteaux
- Type of part
- PCBs (control boards)
- Units in stock
- 1 unit
- 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.
- Fuse
- 125 mA T, 250V
- Transformer manufacturer
- Myrra












