- Boilers
- Gas boiler
E09
Domusa E09 on a gas boiler: water circulation failure
Risk level
Medium
Proceed carefully and stop if the check is unclear.
Urgency
Medium
Quick answer
Domusa E09 is the Avanttia NG alarm for a water circulation failure. Note the code and the pressure on the display, press RESET once only and, if the code comes back, stop and call the official Domusa SAT.
Safety first
Stop and check this first
- If you smell gas, open doors and windows, shut the main gas valve only if it is safe to reach, touch no switches, light no flames, leave the home and phone your gas distributor's emergency line or 112.
- Press RESET once at most. If E09 comes back, leave the boiler off and call the SAT instead of restarting it several times.
- Never remove the casing or try to reach any sealed component inside the boiler: Domusa limits servicing to its authorised staff.
Safe checks you can perform
- Read the code and the pressure on the display
- Press RESET once
- The SAT checks pressure, valves and venting
Leave these tasks to a qualified professional
- Do not attempt this professional task: Circulation diagnosis by the official SAT
- Do not attempt this professional task: Air purge and pressure top-up
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.
Circulation diagnosis by the official SAT
What they doAn authorised Domusa technician finds out why water is not flowing as it should: pressure, valves, air and pump, in that order.
They must show youthe pressure they read, the state of the flow and return valves and the boiler error history.
In writingthe E09 code, the cause found and the part or setting that was touched.
Air purge and pressure top-up
What they doIf there is air or too little water, the technician runs the boiler purge function and refills the circuit with the filling valve to a suitable pressure.
They must show youthe pressure before and after the purge.
In writingthe final pressure and whether E09 came back during testing.
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.
Read the code and the pressure on the display
- Who:
- you, no tools.
- How:
- Look at the screen without opening anything: see whether E09 flashes with the error symbol and what the digital pressure gauge shows.
- Result that matters:
- Below 0.5 bar the boiler raises E02 rather than E09, so that reading tells the two cases apart.
- If you see E02 or a clearly low pressure, write it down and tell the SAT; do not drain or top up the circuit yourself.
- If the pressure looks normal and only E09 shows, go on to the single RESET in the next step.
- Evidence to keep:
- a photo of the display showing the code and the pressure value.
Evidence: Domusa Teknik Avanttia NG operation user guide (CDOC001980)
Press RESET once
- Who:
- you, no tools.
- How:
- Press the RESET button on the panel one time, as the alarm table says, and wait to see whether the boiler starts.
- Result that matters:
- What matters is whether E09 clears and the boiler heats normally again.
- If the code stays away and you have heating, note the date and time in case it repeats.
- If E09 returns, do not press RESET again:
- leave the boiler as it is and call the official Domusa SAT.
- Evidence to keep:
- date, time and how many times the code has appeared.
Evidence: Domusa Teknik Avanttia NG operation user guide (CDOC001980)
The SAT checks pressure, valves and venting
- Who:
- official Domusa SAT or an authorised installer.
- How:
- Confirms the pressure sits between 1 and 1.5 bar, that the flow and return valves are open and that no air is left; can read the last 10 errors in the Info Menu.
- Result that matters:
- A pressure or valve cause is fixed on the spot; if all is in order, the fault points to the pump or the control.
- If pressure or a valve explains it, it is corrected and the boiler is watched to make sure E09 does not return.
- If the circuit is correct and E09 persists, the technician goes on to the pump, its wiring and the electronic control.
- Evidence to keep:
- the error history list, the measured pressure and the state of the valves.
Evidence: Domusa Teknik Avanttia NG, instrucciones de instalación y funcionamiento (CDOC001924) · Domusa Teknik Avanttia NG operation user guide (CDOC001980)
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
- Domusa Teknik
- Product type
- Gas boiler
Known code variants
- AEG freezer error E09
- AEG fridge freezer code E09
- Avanttia NG E09
- Balay dishwasher E09
- Balay E09
- Bosch E09
- caldera Domusa E09
- code erreur E09 lave-vaisselle Siemens
- codice E09 Siemens
- codigo E09 frigorifico combi AEG
- código E09 Siemens
- combi Electrolux E09 congelador
- Domusa boiler E09
- Domusa E 09
- Domusa E09 error
- Domusa fallo de circulación de agua
- Domusa water circulation failure
- E-09
- E09 lavavajillas Balay
- E09 Siemens dishwasher
- E9
- Electrolux E09 freezer not cold
- Electrolux fridge error E09
- Electrolux fridge freezer E09
- Electrolux frigorífico E09
- erreur E09 Siemens
- Error E09 Balay
- error E09 congelador AEG
- Error E09 Domusa
- error E09 frigorífico Electrolux
- error E09 lavavajillas Siemens
- errore E09 lavastoviglie Siemens
- Fehlercode E09 Siemens
- Siemens dishwasher E09
- Siemens E09
- Siemens Geschirrspüler Fehler E09
What it means
In the Avanttia NG alarm table, E09 is listed as water circulation failure and the boiler flashes it after its continuous self-test. Domusa says to press RESET and contact the SAT if the error persists. The code alone does not prove that the pump, a valve or a sensor is faulty: it only says water is not circulating as expected, and an authorised technician has to find the reason. The installation manual used here is in Spanish.
Warnings and stop conditions
- Higheditorial warning
If you smell gas, open doors and windows, shut the main gas valve only if it is safe to reach, touch no switches, light no flames, leave the home and phone your gas distributor's emergency line or 112.
Evidence: Domusa Teknik Avanttia NG operation user guide (CDOC001980)
- Mediumeditorial warning
Press RESET once at most. If E09 comes back, leave the boiler off and call the SAT instead of restarting it several times.
Evidence: Domusa Teknik Avanttia NG operation user guide (CDOC001980)
- Highsource verified
Never remove the casing or try to reach any sealed component inside the boiler: Domusa limits servicing to its authorised staff.
Evidence: Domusa Teknik Avanttia NG operation user guide (CDOC001980)
Symptoms and causes
Probable causes · in order
- Water pressure too lowPossible
The English guide describes a lock-out below 0.5 bar in which the burner and the circulation pump stop. A leak or maintenance work can lead to it.
Evidence: Domusa Teknik Avanttia NG operation user guide (CDOC001980)
- Flow or return valves shutPossible
At commissioning the installation manual (Spanish) asks the installer to confirm that any flow and return valves are open. A closed valve would block water through the circuit.
Evidence: Domusa Teknik Avanttia NG, instrucciones de instalación y funcionamiento (CDOC001924)
- Air in the heating circuit weakens circulationPossible
The boiler has an air purge function that runs the pump and the 3-way valve to clear air from the system. Trapped air can leave the circulation too weak.
Evidence: Domusa Teknik Avanttia NG operation user guide (CDOC001980)
- Pump, its wiring or the electronic controlLess common
The table does not separate a stopped pump from its wiring or from the electronics. Only the SAT can test that, and you should never open the boiler to try.
Evidence: Domusa Teknik Avanttia NG operation user guide (CDOC001980)
Virtual technician
Does E09 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
Domusa Teknik Avanttia NG, instrucciones de instalación y funcionamiento (CDOC001924)
Domusa Teknik · 2023 · manual
- 2
Domusa Teknik Avanttia NG operation user guide (CDOC001980)
Domusa Teknik · 2020 · manual
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