Saunier Duval Thema Condens AS 25-A Primary Condensing Heat Exchanger — Sermeta Ref. 14.16.01.00442
Sermeta condensing combustion chamber/primary heat exchanger for Saunier Duval Thema Condens AS boilers. It transfers heat from the burner to the circuit and collects the condensate. A fault can cause leaks, overheating, or ignition problems. Check the SERMETA 14.16.01.00442 PCB and the parts list for your model before installation.
VAT included
Consult via WhatsAppHow to check if the ref. 14.16.01.00442 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.
Symptoms and faults that the combustion chambers 14.16.01.00442 solve.
Common symptoms and faults
- 01
Acid dripping from the bottom of the boiler or rust marks on the casing/fan
Cause: Crack/porosity in the chamber or joints of the combustion module
Visual inspection with a flashlight; check the pH of the drip (condensate ~3.5–4.0); white traces and marks on the fan.
- 02
Lockouts due to F.28/F.29 after several ignition attempts
Cause: Condensate drainage from the heat exchanger blocked or flooded chamber
Empty/clean the siphon and pipe; pour water into the collector to check free flow to the drain.
- 03
Shots due to overheating or very high ΔT (F.23/F.24) with boiling noises
Cause: Internal clogging of the primary circuit due to sludge or scaling
Measure ΔT supply/return at different power levels; if abnormal with the correct pump, perform controlled chemical cleaning or replace.
- 04
Smell of combustion or condensate marks near the fan-chamber coupling.
Cause: Deformed joint between the chamber and the fan or loose screws
Front disassembly, inspection of O-rings/flat gaskets, and re-tightening to the torque specified by the manufacturer (replace gaskets).
- 05
F.42 after intervention in the combustion block
Cause: Incorrect coding resistance of the heat exchanger not connected.
Check the coding bundle of the heat exchanger and values in diagnostics according to the manual.
Fault codes from Saunier Duval that this spare part resolves.
| Code | Fault | Diagnosis and solution |
|---|---|---|
| F.28 | Start-up fault: ignition failed | Check gas supply/pressure, electrode, and ground connection. Clean siphon and condensate hoses; an accumulation in the chamber can extinguish the flame. If the issue persists, inspect for obstruction or leak in the heat exchanger/assembly. |
| F.29 | Operating fault: failed ignition attempts | Check the flue gas recirculation and evacuation; clean the condensate drain. A flooded chamber or defective joints can extinguish the combustion during the cycle. |
| F.32 | Fault: fan | Check the connector and rotation of the fan. If there are signs of condensation on the fan, inspect the tightness of the chamber-fan and the drainage of the heat exchanger. |
| F.68 | Flame signal fault (unstable) | Check the air/gas mixture and ignition. Clear the condensate drain; turbulence or pooling in the chamber affects ionization. |
| F.23 | Safety shutdown: excessive temperature variation | Bleed the installation and check the pump. If ΔT remains high, check for scaling/sludge in the primary; it may require chemical cleaning or replacement. |
| F.24 | Safety shutdown: temperature rise too fast | Check the flow and air in the circuit. A partially obstructed primary causes a rapid temperature rise; inspection and cleaning/replacement. |
| F.83 | Insufficient supply/return temperature modification upon startup | With P.01 running, if the temperature does not change, confirm the flow rate and sensors. A clogged primary reduces heat exchange. |
| F.42 | Fault in coding resistor (possible with F.70) | Check the coding resistance in the heat exchanger harness and its connector. If the module has been replaced, install the correct harness. |
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 combustion chambers Saunier Duval 14.16.01.00442
- Catalogue reference
- 14.16.01.00442
- Brand
- Saunier Duval
- Type of part
- Combustion chambers
- 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.
- type
- Monobloc condensing combustion chamber / primary heat exchanger
- manufacturer_component
- Sermeta
- ref_part_on_board
- 14.16.01.00442
- state
- refurbished
- boiler_family_destination
- Saunier Duval Thema Condens AS (check with official parts list)
- boiler_power_range_associated (AS 25-A, 50/30 °C)
- 6.6–26.7 kW
- gas_boiler_associated_category
- II2H3P
- boiler supply voltage and frequency
- 230 V, 50 Hz
- Prior gas and power cut. Wait for the unit to cool down.
- Close the valves and bleed the circuit; empty and clean the condensate siphon before and after intervening.
- Always use new gaskets (single-use) and respect the tightening pairs and sequences indicated by the manufacturer.
- After installation: gas/water tightness test, combustion verification (CO₂), and absence of condensate leaks.
- Respect the original flue gas evacuation and air intake; do not obstruct the condensate drainage.
- Parameterization and checking with diagnostic codes after replacement; clear fault memory and validate operation.
Frequently asked questions about combustion chambers 14.16.01.00442
How do I confirm that it is suitable for my Thema Condens AS?
I have F.28/F.29. Is it always the heat exchanger?
Can I clean the heat exchanger instead of replacing it?
Do you need to adjust anything after replacing it?
