3-Way Valve 24V Saunier Duval Thema F 23 E Ref. 05740400
If you notice that there is hot water but no heating, or that both circuits are mixing, you may need the 3-Way Valve 24V Saunier Duval Thema F 23 E. This valve is responsible for directing water between the heating circuit and the domestic hot water circuit. When it fails, you may receive fault codes such as F.318, F.326, or F.081. It is compatible with boilers from the Thema, Themaplus, and Combitek ranges, among others. It is recommended to replace it when these malfunction symptoms occur.
Saunier Duval boilers compatible with reference 05740400
Three-way valve with reference 05740400. Seven confirmed compatibilities: Thema F 23 E and Thema C 23 E.
Proven compatibility
| Boiler model | Family | Verification |
|---|---|---|
| Saunier Duval Thema F 23 E | Thema | Contrasted |
| Saunier Duval Thema C 23 E | Thema | Contrasted |
| Saunier Duval Thema 23 | Thema | Contrasted |
| Saunier Duval Themaplus C 23 E | Themaplus | Contrasted |
| Saunier Duval Themaplus F 23 E | Themaplus | Contrasted |
| Saunier Duval Combitek C 23 | Combitek | Contrasted |
| Saunier Duval Combitek F 23 | Combitek | 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. 05740400 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 05740400. 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 3-way valve 05740400 resolves.
The 3-way valve diverts water between heating and domestic hot water. These are the typical symptoms and what to do:
Common symptoms and faults
- 01
There is no hot water or heating, and the problem switches circuits without a clear pattern.
Cause: The 24V actuator is not receiving the command or does not have enough power to fully move the damper.
Check if the actuator makes noise or moves when requesting hot water; if it doesn't move, suspect the wiring or power supply before the valve.
- 02
The motor can be heard trying to turn, but the boiler does not switch circuits.
Cause: The internal gear of the actuator is worn out or the shutter is stuck and the motor cannot overcome the resistance.
Listen to see if the noise of effort occurs in all cycles or only sometimes, to differentiate between a temporary blockage and advanced wear.
- 03
The valve gets stuck halfway, without completing the circuit change.
Cause: The actuator loses its position reference and stops before completing its travel.
Turn off and then restore power to the boiler to check if the gas valve resets and completes its cycle before replacing it.
- 04
The noise when switching circuits is much louder than before.
Cause: The mechanical stop of the actuator is worn out and hits at the end of each stroke.
Compare the noise over several consecutive cycles; if it increases over time, it indicates wear of the actuator and not a one-time fault.
Fault codes from Saunier Duval that this spare part resolves.
| Code | Fault | Diagnosis and solution |
|---|---|---|
| F.318 | The 3-way motorised valve is not moving. | The 3-way valve (actuator or gears) is blocked or without power, so it does not switch between DHW/heating; check by activating the service test and checking voltage/continuity at the motor connector. |
| F.326 | The hydraulic test of the sensor and the actuator has determined that at least two hydraulic components are not functioning. | If the 3-way valve is blocked or disconnected, the hydraulic test detects multiple faults; check the valve movement from the test menu and inspect the connector/wiring harness or replace the assembly if it does not operate. |
| F.081 | The boost has failed. | The brand documents the 3-way valve as a possible cause when it is defective or blocked; confirm by actuating it in service test and, if it does not switch or consumes without turning, replace the valve/motor and check the wiring. |
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 05740400 three-way valve.
- Catalogue reference
- 05740400
- Brand
- Saunier Duval
- Type of part
- 3-way valves
- Units in stock
- 0 units
- 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.
- voltage
- 24 V
Manuals and technical documentation
Official documentation of the boiler, useful for locating the part and cross-referencing the fault codes.
- Saunier Duval Thema F 23 E Manual (PDF)Document © Saunier Duval, provided as a technical reference.
Frequently asked questions about the 3-way valve 05740400
What voltage does the actuator of this valve Ref. 05740400 operate at?
Is this gas valve compatible with the Saunier Duval Themaplus C 23 E?
What fault in a Combitek C 23 requires changing this gas valve?
Spare parts related to Saunier Duval Thema
