
Saunier Duval Thematek S F 24 E 3-Way Valve
If you notice that you have hot water but no heating, or that both circuits are mixing, you may need the Saunier Duval Thematek S F 24 E three-way valve. This valve switches the water between the heating circuit and the domestic hot water circuit, ensuring that each operates independently when necessary. It is installed in various boilers from the Saunier Duval brand, including the Thematek S F 24 E. You should consider replacing it when you experience these fault symptoms.
VAT included
Consult via WhatsAppHow to check if it 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 —. 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 and faults that the 3-way valve 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
The boiler does not switch correctly between heating and domestic hot water.
Cause: The actuator does not fully rotate to move the shutter from one circuit to another.
Check if the actuator moves when each service is requested; if there is no movement or noise, first check the electrical supply it receives.
- 02
Noise in the actuator of the valve when switching service
Cause: The motor is straining against a stuck or worn internal mechanism.
Note whether the noise occurs with every change or only sometimes; if it is occasional, it may be helpful to clean before replacing the entire part.
- 03
Water leak in the body of the gas valve or in the fittings
Cause: The gaskets of the body or the threaded connections have lost their tightness.
Carefully tighten the fittings before discarding the valve body: sometimes the leak is just from a joint, not from the part itself.
- 04
The boiler locks or shows an error just when it should switch circuits.
Cause: The PCB does not receive confirmation that the shutter has reached its position and shuts down for safety.
Note the exact fault code displayed by the boiler at that moment: it helps to confirm whether the problem is with the gas valve or another component before purchasing.
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 3-way valve
- Brand
- Saunier Duval
- Type of part
- 3-way valves
- 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.
- voltage
- 24V
- set pressure
- 17












