Electronic Technical Report issued on: 06/14/2026
WARNING: This appliance is connected to the mains electricity and reaches temperatures capable of causing severe burns. It is mandatory to always unplug it and let it cool down completely before any disassembly or cleaning. If the physical intervention is complex, it is recommended to rely on a qualified technician for your safety. ReeFix provides this diagnosis EXCLUSIVELY for educational and informational purposes.
Excessive internal calcification and clogged Micro-Calc filter. The probability of this being the main cause is very high (70-85%). Your Tefal FV9845 iron expels brown water and triggers the anti-calc indicator light because minerals in the water (calcium, magnesium) have accumulated, forming internal scale. These obstruct the steam channels, the vaporization chamber, and, in particular, the Tefal FV9845 Micro-Calc Filter designed to capture them. Brown water indicates that, in addition to limescale, rust particles or burnt organic residues have also dissolved. The alarm light is the iron's internal signal indicating an obstruction or reduced efficiency due to these deposits. This often happens when the filter is not maintained or if incorrect types of water are used (such as pure distilled water or scented water, which are not recommended by the manufacturer).
Key signs:
Counter-example: If the iron does not heat up at all, the problem might lie in the thermostat or heating element, not just calcification.
If after cleaning the filter and holes the problem persists (brown water, indicator light on), it is likely that the Tefal FV9845 Micro-Calc Filter is physically damaged or completely saturated and needs replacement (spare part cost €15-30), or that the scale is too extensive in the internal channels and the dispensing valve, requiring professional disassembly.
Costs and Decision:
Output for technician: The Tefal FV9845 iron has the anti-calc indicator light on and is leaking brown water from the soleplate. Standard cleaning of the Micro-Calc filter has been attempted. Verify the saturation status of the filter, the integrity of the drip dispensing valve, and the extent of calcification or burning in the soleplate's vaporization chamber.
Prevention tip: Use tap water (mixed 50% with demineralized water only if very hard). Absolutely avoid 100% pure distilled water, tumble dryer condensate water, or scented water: these are the primary causes of brown drips and premature wear in Tefal irons. Clean the Micro-Calc filter every 1-3 months.
If standard cleaning and filter washing do not resolve the issue -> consider replacing the Tefal FV9845 Micro-Calc Filter; if the problem persists, consult a technician. Otherwise, if the repair estimate approaches the cost of a new one, replace the device.