- Boilers
- Tankless gas water heater
F164
Vaillant F.164 on a gas water heater: 45 minute run limit
Risk level
Medium
Proceed carefully and stop if the check is unclear.
Urgency
Medium
Quick answer
F.164 on the Vaillant turboMAG plus means the burner switched itself off after 45 minutes of continuous running. The manual says to close the hot tap briefly; if it appears without such a long draw, call a technician.
Safety first
Stop and check this first
- If you smell gas while the turboMAG plus shows F.164, do not operate switches, plugs, doorbells or phones, avoid any flame, open doors and windows if you can, close the meter or main gas valve and the appliance gas tap if possible, warn neighbours without ringing, leave the building, keep others out and call the emergency services and the gas supplier emergency line from outside.
Safe checks you can perform
- Close the hot tap for a moment
- Check which taps were left open
- Use the general reset if it will not start
Leave these tasks to a qualified professional
- Do not attempt this professional task: Check the safety devices
- Do not attempt this professional task: Annual inspection of the heater
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.
Check the safety devices
What they doIf F.164 appears without such a long continuous draw, the technician verifies that the turboMAG plus supervision and safety devices work correctly.
They must show youthe safety device checks.
In writingthe result for each device checked.
Annual inspection of the heater
What they doDuring the visit they carry out the annual inspection the manufacturer requires and check operation and tightness before closing the appliance.
They must show youthe heater running without F.164 after the inspection.
In writingthe inspection tasks done and the date.
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.
Close the hot tap for a moment
This is the step both manuals give for F.164: shut the hot tap for a few seconds and open it again. The turboMAG plus should light again if no other message remains.
Evidence: Vaillant turboMAG plus MAG ..5/1-5 RT, instrucciones de funcionamiento 0020261985_00
Check which taps were left open
Walk round the home and see whether a hot tap was left running or someone was filling a bath. In bath filling mode the heater beeps at 42 minutes if filling has not been closed, before the F.164 cut-off.
Evidence: Vaillant turboMAG plus MAG ..5/1-5 RT, instrucciones de funcionamiento 0020261985_00
Use the general reset if it will not start
If there is still no hot water after closing the tap, the user manual allows opening and closing the tap several times, switching off and on and pressing the reset button. If F.164 returns without a long draw, call.
Evidence: Vaillant turboMAG plus MAG ..5/1-5 RT, instrucciones de funcionamiento 0020261985_00
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
- Vaillant
- Product type
- Tankless gas water heater
Known code variants
- F.164
- turboMAG F.164
- turboMAG plus F164
- Vaillant F.164
What it means
The turboMAG plus has a safety cut-off: if it runs constantly for more than 45 minutes, it interrupts the gas supply. F.164, run time limit active, is the message from that protection. The fault table gives a single cause, the burner shutting down automatically after 45 continuous minutes, and a single remedy, closing the hot tap for a moment. The user manual repeats that step when the heater stops delivering hot water. The manufacturer does not present it as a component failure.
Warnings and stop conditions
- Criticaleditorial warning
If you smell gas while the turboMAG plus shows F.164, do not operate switches, plugs, doorbells or phones, avoid any flame, open doors and windows if you can, close the meter or main gas valve and the appliance gas tap if possible, warn neighbours without ringing, leave the building, keep others out and call the emergency services and the gas supplier emergency line from outside.
Evidence: Vaillant turboMAG plus MAG ..5/1-5 RT, instrucciones de funcionamiento 0020261985_00
Symptoms and causes
Probable causes · in order
- More than 45 minutes of continuous runningCommon
The burner ran without a break for 45 minutes, for example with a hot tap open throughout, and the protection cut the gas.
Evidence: Vaillant turboMAG plus MAG ..5/1-5 RT, instrucciones de instalación y mantenimiento 0020261986_00
Virtual technician
Does F164 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
- 2
Vaillant turboMAG plus MAG ..5/1-5 RT, instrucciones de funcionamiento 0020261985_00
Vaillant · 2018 · manual
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