3-WAY Valve Mechanism Saunier Duval Hydraulic Isofast F 35 Ref. 0020136956
RefurbishedSaunier Duval3-way valves

3-WAY Valve Mechanism Saunier Duval Hydraulic Isofast F 35 Ref. 0020136956

40 €VAT includedIn stock · 1 unit

3-way valve: refurbished spare part that diverts water between heating and domestic hot water. Useful if it provides hot water but does not heat radiators, or vice versa. Compatible with Isofast F 35E, Isofast 21 F35, Isofast F 30E (ref. 0020136956). Includes a one-year warranty and delivery within 2–4 working days in the EU.

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Delivery in 2–4 working days
1-year warranty
14-day return
Technical support

Key Data

Reference
0020136956
Brand
Saunier Duval
Type of part
3-way valves
Available units
1 unit in stock
Status
Refurbished
Warranty
1 year
Shipping
2–4 working days (EU)
Return
14 days

The same part (ref. 0020136956) equips these models. Verified compatibility; check the reference before purchasing.

Isofast

  • Isofast F 35E
  • Isofast 21 F35
  • Isofast F 30E

Isotwin

  • Isotwin C 30
  • Isotwin F 30H

Isomax

  • Isomax F 35E
  • Isomax Condens F30
  • Isomax Condens F35E

Themafast

  • Themafast C 25E
  • Themafast C 30E
  • Themafast F25E
  • Themafast F30

Thema

  • Thema F 24E
  • Thema F 25E

Condens

  • Condens F 24E
  • Condens F 30E

Semia

  • Semia F25
  • SemiaTek C 24
  • SemiaTek F 24

Fault codes related to this part (not the entire boiler). They usually have more possible causes: first rule out electrodes, wiring/connections, and gas supply. Verified with ≥3 sources.

CodeWhat does it mean?Cause and diagnosis (this part)
F.20Safety shutdown: temperature limiter.If the 3-way valve (priority valve) gets stuck or disconnected, it does not divert the flow and causes overheating in the primary. Verify movement/position by performing an actuator test and checking the connector and continuity of the valve motor.
F.318The 3-way motor valve is not moving.Mechanical/electrical fault of the 3-way mechanism prevents its movement. Check with actuator test, motor voltage, and condition of connectors/harness; replace if it does not operate.
F.326The hydraulic test of the sensor and actuator has detected that at least two hydraulic components are not functioning.A blocked/disconnected 3-way valve causes the hydraulic self-test to fail. Check the operation of the 3-way motor with an actuator test, inspect the connector/harness, and replace if it is seized.
F.081The boost has failed.If the 3-way valve does not prioritize DHW (blockage or defective motor), the boiler cannot perform the boost/preload. Check that when DHW is demanded, the valve switches to the PCB (actuator test) and that it receives power; replace if it does not change position.
How do I know if this 3-way valve is for my boiler?
Verify the reference 0020136956 printed and ensure your model is on the list of compatible ones; also compare the connections with the original part.
What is it used for?
The 3-way valve diverts the water between the heating circuit and the domestic hot water (DHW) circuit.
Does it provide hot water but not heat the radiators (or vice versa)?
Typical symptom that the valve or its motor is not switching; check the actuator motor and ensure the body is not seized.
Which models is it suitable for?
Part shared by various models (see Compatibility). If your model does not appear, send us a photo of the marking and we will confirm it.
Installation and recommendations
Check if you need the motor, the body, or the complete assembly.
What does refurbished mean and what coverage does it have?
Part removed from a boiler out of service, inspected and tested. Includes 1-year warranty and 14-day return policy. Delivery within 2–4 working days in the EU.
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