Saunier Duval Themis 23E PCB Ref. 05712800
The Saunier Duval Themis 23E PCB is the component that controls key functions such as ignition, burner modulation, the pump, and the safety features of the boiler. When it fails, the boiler may not start, become locked, or exhibit erratic operation, displaying faults such as F.28, F.61, F.62, F.63, or F.64. This part is compatible with several models from the Thelia and Themis ranges, among others. A technician must confirm through diagnosis whether replacement is necessary when these symptoms or faults in the boiler's operation are detected.
- Type of part
- PCBs (control boards)
- Status
- Refurbished
- Catalogue reference
- 05712800
- Warranty
- 1 year
Saunier Duval boilers compatible with reference 05712800
PCB with reference 05712800. Three confirmed compatibilities: 23 E and 623 E.
Verified compatibility
| Boiler model | Family | Verification |
|---|---|---|
| Saunier Duval 23 E | Thelia | Verified |
| Saunier Duval 623 E | Thelia | Verified |
| Saunier Duval 23 E | Themis | Verified |
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. 05712800 is the part for your boiler
The part reference, model, and equipment revision must be verified against the manufacturer's documentation.
- Find the reference printed on the installed part and check whether it matches the catalogue reference 05712800. If it is not visible, do not identify the part by 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 that require diagnosis on the PCB 05712800
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 shows no signs: no lights, no display, and it doesn't attempt to turn on.
Cause: The PCB does not activate its control circuit and does not send commands to the other components.
Check that power is reaching the PCB and that its internal fuse is not blown before replacing it.
- 02
An error code appears on the screen that does not clear when restarting.
Cause: The microprocessor on the PCB detects an incorrect reading and locks the boiler for safety.
Check the sensor or component related to that specific fault code before considering the PCB as faulty.
- 03
The remote control or the thermostat do not control the boiler, as if it is not responding.
Cause: The PCB manages communication with the remote control, and if its bus controller fails, it does not understand the commands.
Check the wiring and the bus connectors between the PCB and the control before replacing the PCB.
- 04
The boiler turns off by itself intermittently, without a fixed pattern.
Cause: An occasional fault in the PCB, such as a loose solder joint, causes the loss of a safety signal randomly.
Check that all the connectors on the PCB are properly tightened and free of rust before replacing it.
Fault codes Saunier Duval that require diagnosis
| Code | Fault | Technical checks |
|---|---|---|
| F.28 | Fault: unsuccessful ignition on start-up | The PCB may fail (defective electronics) or have the multi-connector improperly plugged in, preventing ignition management; check power supply and ground connections, continuity of the harness, and seating of the multipin on the PCB before replacing it. |
| F.61 | Gas valve activation error | This symptom may be related to the part, but it does not confirm that it is faulty. A technician must check the equipment and its inspection according to the manual before deciding on a repair or replacement. |
| F.62 | Gas valve disconnection delay error | An electronic fault in the PCB may maintain a delayed shutdown command or late flame detection; check the control signal at the gas valve terminals, and if the shutdown command persists without an external cause, replace the PCB. |
| F.63 | EEPROM fault | Fault in the PCB memory (EEPROM) or data corruption; confirm with resets/auto-test, check for stable voltages, and if the fault persists, replace the PCB. |
| F.64 | Electronic fault / NTC | The electronics of the PCB are declared faulty or misinterpret sensors due to an internal error; check sensors/harness and, if they are correct, the cause is the PCB. |
| F.65 | Fault: PCB temperature | The PCB detects overheating or a fault in its internal thermal circuit; check ventilation/environment and temperature in the electronic box, and if it reappears without an external cause, replace the PCB. |
| F.67 | Fault: electronics/flame | The ionisation signal is not plausible due to a fault in the flame circuit on the PCB; check the electrode/wiring and, if the signal remains abnormal with correct hardware, the cause is the electronics of the board. |
| F.70 | Invalid product code (DSN) | The display and/or printed circuit board has been replaced without reconfiguring the product code/DSN; check with the service menu and reprogram the code or, if not possible, replace/configure the correct 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 05712800 PCB.
- Catalogue reference
- 05712800
- Uniclima internal SKU
- PLCTHMS23
- Brand
- Saunier Duval
- Type of part
- PCBs (control boards)
- Units in stock
- 4 units
- Status
- Refurbished
- Warranty
- 1 year
- Shipping
- Delivery time shown at checkout
- Return
- 14 days
Part data and available documentation
Contrast the label codes, PCB, and revision with the installed part; they are not necessarily equivalent references.
- Supply voltage
- 230V
- Fuse
- 80mA T
- Relay, coil voltage
- 24V DC
- Relay, contacts
- 8A / 250V~ / AC1
- PCB code (component side)
- 8/050151H
- Date / manufacturing batch
- 97/03/08, batch 9720
Manuals and technical documentation
Official documentation of the boiler, useful for locating the part and cross-referencing the fault codes.
- Saunier Duval 623 E manual (PDF) Document © Saunier Duval, provided as a technical reference.
Frequently asked questions about the PCB 05712800
Does this PCB from the Themis 23E also work for the Thelia 623E?
Does the code recorded on the PCB match the reference 05712800?
What voltage does the PCB of the Thelia 623 operate at?
What components does this PCB include besides the relay RYA3002A?
Spare parts related to Saunier Duval Thelia
