Saunier Duval Thema NOx F25 Air Pressure Switch - Ref. 0020124897 / 0020111755
Differential air pressure switch for Saunier Duval Thema Condens 25-A, Thema NOx F25, and Themafast NOx F25/F30 boilers. Set to 59/24 Pa for opening/closing and electrical load 1(0.5)A at 250V~, according to the label. It is engraved with the code 605.99882; the catalog reference 0020124897 corresponds to 0020111755 printed on the part. The replacement requires first confirming the fault of the part through technical diagnosis, even when the boiler locks due to a fault in the air pressure switch.
- Type of part
- Pressure switches
- Status
- Refurbished
- Catalogue reference
- 0020124897
- Warranty
- 1 year
Saunier Duval boilers compatible with reference 0020124897
Pressure switch with reference 0020124897. Two confirmed compatibilities: Thema NOX F25 and Themafast NOX F30.
Proven compatibility
| Boiler model | Family | Verification |
|---|---|---|
| Saunier Duval Thema NOx F25 | Thema NOX / Themafast NOX | Contrasted |
| Saunier Duval Themafast NOx F30 | Thema NOX / Themafast NOX | 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. 0020124897 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 0020124897. 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 that require diagnosis in the pressure switch 0020124897
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 is locking out and the display shows a fault or blockage of the pressure switch.
Cause: This pressure switch compares the pressure between two connections and, if the difference does not reach the required value, it does not allow the ignition.
Make sure that both pressure connections are properly connected and in the correct order; if they are swapped, it can cause the same fault as a broken part.
- 02
The extractor works correctly, but the burner never ignites.
Cause: If the pressure difference does not reach the necessary point, the electronics do not receive the signal to ignite, even though the fan is working properly.
Check that both silicone tubes are free of obstructions, breaks, or kinks before replacing the part.
- 03
The fault is intermittent: some days it starts without issues and other days it gets stuck.
Cause: A contact that activates the system near its set point may fail due to small variations in pressure or dirt in the mechanism.
Carefully clean the pressure connections and make sure there is no condensation accumulated in the pipes.
Fault codes Saunier Duval that require diagnosis
| Code | Fault | Technical checks |
|---|---|---|
| F2 | Safety lack of draft (SRC) or pressure switch. | The air pressure switch does not switch when the fan starts due to lack of vacuum or internal fault; it can be checked by measuring continuity at its terminals during start-up and inspecting/cleaning tubes and venturi. |
| F33 | Air flow fault. | The air pressure switch remains open and does not confirm flow/depression, blocking ignition; check with a multimeter if it changes state when the fan is activated and inspect the condition of hoses and venturi connections. |
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 Saunier Duval pressure switch 0020124897
- Catalogue reference
- 0020124897
- Uniclima internal SKU
- PCSDTNF25B1
- Brand
- Saunier Duval
- Type of part
- Pressure switches
- Units in stock
- 3 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.
- Pressure differential (open/close)
- 59/24 Pa
- Electric charge
- 1(0.5)A / 250V~
- Manufacturer code
- 605.99882
Manuals and technical documentation
Official documentation of the boiler, useful for locating the part and cross-referencing the fault codes.
- Saunier Duval Thema Nox F25 Manual (PDF) Document © Saunier Duval, provided as a technical reference.
Frequently asked questions about the pressure switch 0020124897
Is this air pressure switch compatible with the Thema NOX F25 boiler?
Can I use this pressure switch in the Themafast NOX F30 boiler?
What fault codes indicate a failure in this pressure switch?
What electrical load does the air pressure switch Saunier Duval Thema NOx F25 support?
What pressure is the air pressure switch of the Thema NOX F25 set to?
Are the references 0020124897 and 0020111755 of the pressure switch equivalent?
