Saunier Duval Thematek SF 24 E Air Pressure Switch Ref. S1008900
Air pressure switch for Saunier Duval boilers from the Thematek, ThemaClassic, Thesi, Combitek, F AS, and Micra range. It detects the air pressure generated by the fan and allows ignition only if it is correct. The label on this unit indicates a setting of 80/68 Pa. It is replaced when the boiler does not ignite or gets stuck in the extraction phase.
VAT included
Consult via WhatsAppSaunier Duval boilers compatible with reference S1008900
Pressure switch with reference S1008900. Seven confirmed compatibilities: ThemaClassic F24 E and ThemaClassic F25 E.
Proven compatibility
| Boiler model | Family | Verification |
|---|---|---|
| Saunier Duval ThemaClassic F24 E | ThemaClassic | Contrasted |
| Saunier Duval ThemaClassic F25 E | ThemaClassic | Contrasted |
| Saunier Duval ThemaClassic F AS 24 E | ThemaClassic | Contrasted |
| Saunier Duval ThemaClassic F AS 25 E | ThemaClassic | Contrasted |
| Saunier Duval Thematek SF 24 E | Thematek | Contrasted |
| Saunier Duval Thematek F 24 E | Thematek | Contrasted |
| Saunier Duval Combitek F24 E | 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. S1008900 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 S1008900. 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 pressure switch S1008900 resolves.
The pressure switch controls the air or water pressure to authorize operation. These are the typical symptoms and what to do:
Common symptoms and faults
- 01
The boiler tries to ignite, the fan can be heard, but it stops before the flame appears.
Cause: The pressure switch does not close the air contact sufficiently, and the control board cuts off the ignition attempt for safety reasons.
Check that the silicone tubes of the pressure switch are not bent, loose, or have accumulated condensation.
- 02
The boiler gets locked with a warning related to the extractor or flue gas evacuation.
Cause: If the pressure switch detects less air pressure than required, it prevents the ignition phase from starting even if the fan is operating.
Check that the flue pipe is not blocked by nests, leaves, or ice.
- 03
The extractor operates normally, but the boiler never ignites the flame.
Cause: The pressure switch is the one that authorizes the next step of the cycle; if it does not close the contact, the control unit remains waiting for that signal.
With the boiler running, listen to see if the extractor sounds forced or quieter than usual.
- 04
The fault mainly occurs during strong winds or bad weather, while on other days the boiler ignites without any issues.
Cause: External conditions affect the actual flue gas pressure, and a pressure switch at the limit of its setting may fail only under those conditions.
Note if the fault occurs with wind or rain; if so, check the flue and its external terminal.
Fault codes from Saunier Duval that this spare part resolves.
| Code | Fault | Diagnosis and solution |
|---|---|---|
| F2 | Air deficiency safety (Themaclassic F): flue gas intake/exhaust fault. | The air pressure switch does not switch (does not close) when the fan starts due to lack of depression, fatigued diaphragm, or blocked inlets/tubes; check continuity at its terminals during the pre-purge and inspect tubes to the fan and flue duct. |
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.
Datasheet for the Saunier Duval pressure switch S1008900
- Catalogue reference
- S1008900
- Brand
- Saunier Duval
- Type of part
- Pressure switches
- Units in stock
- 7 units
- Status
- Refurbished
- Warranty
- 1 year
- Shipping
- Delivery time shown at checkout
- 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.
- Opening/closing setting
- 80/68 Pa
- Electrical contact
- 1(0.5)A / 250V~
- Manufacturer code
- 605.99561
- The printed batch code has an ambiguous character between 'Z' and '2'; it does not affect the manufacturer code or the calibration.
Manuals and technical documentation
Official documentation of the boiler, useful for locating the part and cross-referencing the fault codes.
- Saunier Duval Thematek SF 24 E Manual (PDF)Document © Saunier Duval, provided as a technical reference.
Frequently asked questions about the pressure switch S1008900
What fault does this air pressure switch of the Saunier Duval Thematek SF 24 E resolve?
What is the setting of the air pressure switch for the Saunier Duval Thematek SF 24 E?
Is this air pressure switch SSTSF24E compatible with other boilers?
How many models are compatible with this air pressure switch?
What fault code is documented for this pressure switch?
Is it necessary to check the setting of the pressure switch before purchasing?
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