- Boilers
- Gas boiler
F05
Ferroli F05 on a gas boiler: air or fan fault
Risk level
High
Professional inspection is recommended.
Urgency
High
Quick answer
The boiler detected a problem with flue gas evacuation or the fan and stopped. Check from outside that nothing blocks the flue terminal, without touching it, and if F05 persists or turns into A15, call the service centre.
Safety first
Stop and check this first
- If you smell gas: do not switch lights or appliances on or off, do not use flames or a phone indoors, open doors and windows if you can on your way out, leave the home and call your gas supplier's emergency number or the emergency services from outside.
- If you suspect flue gases are not escaping properly, because of a smell or a blocked terminal, keep the boiler off and ventilate until a technician has checked it.
Safe checks you can perform
- Your exact Ferroli boiler model
- Flue terminal seen from outside
- Whether F05 turns into A15
- Inspection by a qualified gas technician
Leave these tasks to a qualified professional
- Do not attempt this professional task: Inspect the flue
- Do not attempt this professional task: Check transducer or fan
- Do not attempt this professional task: Combustion analysis
What a technician must be able to justify
Technician visit
These are the steps they must carry out and show you. Tick them as they work: if steps are skipped, do not accept a part swap.
These are not instructions for opening or handling the equipment yourself. They are the checks that should support a technical conclusion.
Inspect the flue
What they doThe technician checks that the flue duct and terminal are clean and that their length matches the model's manual.
They must show youphotos of the duct and its length against the manual.
In writingwhat was corrected.
Check transducer or fan
What they doWith the boiler de-energised, the technician checks the air pressure transducer wiring (DIVAtop) or measures the 230 V supply and the fan signal (HiTech).
They must show youthe measurement against the specification.
In writingthe part replaced and the reason.
Combustion analysis
What they doAfter the repair, the technician samples fumes and air at the test points on top of the boiler in TEST mode, as Ferroli describes.
They must show youthe analyser report.
In writingthe measured values.
Before accepting a part or repair
Nothing has been shown yet. Do not accept a part swap based on the code alone.
Follow these steps
Note: Follow the documented order. An error code identifies the affected system, but it does not prove by itself which part has failed.
Your exact Ferroli boiler model
- Who:
- you.
- How:
- find the model name on the front or on the rating plate, without opening the casing, and compare it with your boiler's manual.
- Result that matters:
- confirming what F05 means on your model.
- If it is a DIVAtop MICRO LN F:
- F05 relates to the air pressure transducer. If it is a BlueHelix HiTech RRT C: F05 is a fan fault.
- If it is another model:
- check the fault table in its manual before following this page.
- Evidence to keep:
- photo of the rating plate and of the code.
Evidence: Ferroli DIVAtop MICRO LN F instrucciones de uso instalación y mantenimiento · Ferroli BlueHelix HiTech RRT C instrucciones de uso instalación y mantenimiento
Flue terminal seen from outside
- Who:
- you.
- How:
- from the ground, a window or the balcony, look at the flue terminal without touching or dismantling it.
- Result that matters:
- whether anything visibly blocks it.
- If it is blocked:
- switch the boiler off and tell the technician; Ferroli says to check that the flue is clean.
- If it looks clear:
- the blockage may be inside the duct or the cause may be different; continue.
- Evidence to keep:
- photo of the terminal.
Do not climb onto the roof or dismantle the flue duct.
Evidence: Ferroli DIVAtop MICRO LN F instrucciones de uso instalación y mantenimiento
Whether F05 turns into A15
- Who:
- you.
- How:
- watch whether F05 clears on its own, as Ferroli says F codes do, or whether the display moves to A15.
- Result that matters:
- whether the fault repeats.
- If A15 appears:
- on the DIVAtop, F05 occurred 5 times in the last 15 minutes; do not reset again and call the technician.
- If F05 clears and does not return:
- note when it happened for the technician.
- Evidence to keep:
- photos of the codes with the time.
Evidence: Ferroli DIVAtop MICRO LN F instrucciones de uso instalación y mantenimiento
Inspection by a qualified gas technician
- Who:
- a qualified gas technician, preferably from Ferroli's service network.
- How:
- checks the flue and its length, the air pressure transducer wiring or, on the HiTech, the 230 V supply, the tachometric signal and the fan.
- Result that matters:
- which branch of Ferroli's fault table is confirmed by measurements.
- If the cause is found:
- they should explain which measurement confirms it before replacing parts.
- If everything measures correctly and the code returns:
- they should move to the next cause in the table, not replace parts at random.
- Evidence to keep:
- job sheet with the measurements and parts replaced.
Opening the casing or touching the gas valve, electrode, burner or flue is work for the technician only. Ferroli says to disconnect the electrical power supply and close the gas cock upstream before any operation inside the boiler.
Evidence: Ferroli DIVAtop MICRO LN F instrucciones de uso instalación y mantenimiento · Ferroli BlueHelix HiTech RRT C instrucciones de uso instalación y mantenimiento
Still not solved
If the error persists, stop here. See what the technician must do and show you.
Where this code applies
A code is meaningful only inside the right product and version context.
Primary scope
- System
- Boilers
- Brand
- Ferroli
- Product type
- Gas boiler
Known code variants
- Anomalía F05 Ferroli
- calentador Cointra F05
- Cointra F05
- Cointra water heater F05
- CPE T F05
- Error F05 Ferroli
- error F05 lavadora Hotpoint
- error F05 lavadora Indesit
- error F05 lavadora Whirlpool
- F-05
- F5
- Ferroli error F05
- Ferroli F05
- Ferroli F05 boiler
- Ferroli F05 caldera
- Hotpoint F05 error washer
- Hotpoint F05 lavadora
- Hotpoint washer F05 not draining
- Hotpoint washing machine F05
- Indesit F05 error washer
- Indesit F05 lavadora
- Indesit washer F05 not draining
- Indesit washing machine F05
- lavadora Hotpoint F05 no desagua
- lavadora Indesit F05 no desagua
- lavadora Whirlpool F05 no desagua
- Opalia F.05
- Opalia F05
- Saunier Duval F05
- Supreme E TS F05
- Whirlpool F05 lavadora
- Whirlpool F05 washing machine
- Whirlpool washer F05 not draining
- Whirlpool washing machine error F05
What it means
The meaning depends on the model. On the DIVAtop MICRO LN F, F05 means the air pressure transducer did not receive a sufficient minimum value within 25 seconds: incorrect transducer wiring or a flue that is obstructed or not correctly sized; if it occurs 5 times in 15 minutes it becomes A15. On the BlueHelix HiTech RRT C, F05 is a fan fault: no 230 V supply, an interrupted tachometric signal or a faulty fan. It is an F code, temporary.
Warnings and stop conditions
- Criticaleditorial warning
If you smell gas: do not switch lights or appliances on or off, do not use flames or a phone indoors, open doors and windows if you can on your way out, leave the home and call your gas supplier's emergency number or the emergency services from outside.
Evidence: Ferroli DIVAtop MICRO LN F instrucciones de uso instalación y mantenimiento
- Higheditorial warning
If you suspect flue gases are not escaping properly, because of a smell or a blocked terminal, keep the boiler off and ventilate until a technician has checked it.
Evidence: Ferroli DIVAtop MICRO LN F instrucciones de uso instalación y mantenimiento
Symptoms and causes
Probable causes · in order
- Flue obstructed or not correctly sized (DIVAtop)Possible
Ferroli says to check the flue length and that it is clean. It fits after frost, nests or building work near the terminal.
Evidence: Ferroli DIVAtop MICRO LN F instrucciones de uso instalación y mantenimiento
- Air pressure transducer wiring (DIVAtop)Possible
Incorrect transducer wiring. Only visible with the casing open.
Evidence: Ferroli DIVAtop MICRO LN F instrucciones de uso instalación y mantenimiento
- Supply, signal or fan (HiTech)Possible
On the BlueHelix HiTech RRT C: no 230 V supply, an interrupted tachometric signal or a faulty fan.
Evidence: Ferroli BlueHelix HiTech RRT C instrucciones de uso instalación y mantenimiento
Virtual technician
Does F05 still appear after these checks?
Answer a few questions to narrow down the likely cause and the safest next action. Guidance only - it never replaces a professional.
Sources and technical references
- 1
Ferroli DIVAtop MICRO LN F instrucciones de uso instalación y mantenimiento
Ferroli · 2015 · manual
- 2
Ferroli BlueHelix HiTech RRT C instrucciones de uso instalación y mantenimiento
Ferroli · 2021 · manual
Was this entry useful?