- Boilers
- Electric water heater
314
Ariston 314 on Nuos or Lydos heater: repeated ON/OFF lockout
Risk level
Low
Usually safe to check without specialist tools.
Urgency
Medium
Quick answer
On Ariston Nuos Plus S2 Wi-Fi and Lydos Hybrid Wi-Fi heat pump water heaters, error code 314 signals repeated ON/OFF switching and turns off both the heat pump and the electric heating element. Wait at least 15 minutes without touching the button before unlocking with ON/OFF.
Safety first
Stop and check this first
- While error 314 is active, both the electric heating element and the heat pump remain OFF; pressing ON/OFF again before 15 minutes have passed will keep hot water production stopped.
- All power supply circuits must be disconnected before accessing any internal terminals, and maintenance or repairs may only be carried out by qualified personnel.
Safe checks you can perform
- Leave the water heater untouched for at least 15 full minutes
- Unlock the appliance with the ON/OFF button after the 15-minute wait
- Watch the display to see whether a different fault code appears after unlocking
Leave these tasks to a qualified professional
- Do not attempt this professional task: Contact Ariston technical assistance if code 314 persists after waiting 15 minutes
- Do not attempt this professional task: Have a qualified technician inspect the user interface and main board connections
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.
Contact Ariston technical assistance if code 314 persists after waiting 15 minutes
What they doIf code 314 does not clear after waiting at least 15 minutes and unlocking once with ON/OFF, or if it returns without anyone touching the keypad, contact Ariston technical assistance.
They must show youthe keypad unlock test after the 15-minute interval and the last 10 logged faults (installer parameter P30 ERRORS on Nuos Plus S2).
In writingthe Ariston service reference number and the list of error codes stored in the unit's fault history.
Have a qualified technician inspect the user interface and main board connections
What they doAfter disconnecting all power supply circuits from the mains, a qualified technician must check the electrical connections between the user interface panel (HMI) and the main board (tarjeta madre), replacing any faulty board or cable with original Ariston parts.
They must show youthe inspection of the interface connector on the main board and stable operation with no unprompted 314 lockouts.
In writingthe service report detailing the electronic connection check, any replaced parts and the completed function test.
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.
Leave the water heater untouched for at least 15 full minutes
- Who:
- you.
- How:
- when 314 flashes on the display, keep the appliance connected to the power supply and do not press the ON/OFF button or any other key for at least 15 minutes.
- Result that matters:
- completing the mandatory 15-minute lockout timer required by Ariston before unlocking.
- If at least 15 minutes have passed without any button presses:
- proceed to unlock the unit with the ON/OFF button.
- If you press ON/OFF before the 15 minutes are up:
- the unit stays locked with both the heat pump and heating element OFF.
- Evidence to keep:
- note of the time when code 314 was spotted and the time when the 15-minute wait finished.
Evidence: Ariston Nuos Plus S2 Wi-Fi, calentador de agua con bomba de calor: instrucciones para la instalación, el uso y el mantenimiento · Ariston Lydos Hybrid Wi-Fi, calentador de agua eléctrico híbrido: instrucciones de uso y mantenimiento 420010890100
Unlock the appliance with the ON/OFF button after the 15-minute wait
- Who:
- you.
- How:
- once the 15 minutes have elapsed, unlock the appliance using the ON/OFF button (pressing the ON/OFF key twice as specified in the Lydos Hybrid Wi-Fi table, or pressing ON/OFF on the Nuos Plus S2 Wi-Fi) a single time.
- Result that matters:
- clearing code 314 from the display so the heat pump and electric heating element can operate again.
- If the screen returns to the normal water temperature view:
- the repeated ON/OFF lockout has cleared.
- If code 314 stays on screen or comes back without anyone pressing the button:
- do not keep pressing ON/OFF and check for an underlying fault.
- Evidence to keep:
- photo of the display after performing the unlock step following the 15-minute wait.
Evidence: Ariston Nuos Plus S2 Wi-Fi, calentador de agua con bomba de calor: instrucciones para la instalación, el uso y el mantenimiento · Ariston Lydos Hybrid Wi-Fi, calentador de agua eléctrico híbrido: instrucciones de uso y mantenimiento 420010890100
Watch the display to see whether a different fault code appears after unlocking
- Who:
- you.
- How:
- observe the display for a few minutes after 314 clears to check whether another error code or flashing heat pump (HP) or heating element icon appears that originally prompted the repeated resets.
- Result that matters:
- distinguishing a user-triggered 314 lockout from an underlying heat pump or water circuit error.
- If another error code appears on the display:
- write down that code and call technical assistance without repeating rapid ON/OFF resets.
- If code 314 keeps reappearing on its own:
- book a visit from Ariston technical assistance.
- Evidence to keep:
- photo of any subsequent error code or flashing status symbol shown on the screen.
Evidence: Ariston Nuos Plus S2 Wi-Fi, calentador de agua con bomba de calor: instrucciones para la instalación, el uso y el mantenimiento · Ariston Lydos Hybrid Wi-Fi, calentador de agua eléctrico híbrido: instrucciones de uso y mantenimiento 420010890100
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
- Ariston
- Product type
- Electric water heater
Known code variants
- Ariston 314
- Ariston 314 repeated ON/OFF
- Ariston error 314
- Ariston Lydos error 314
- Ariston Nuos error 314
- Attached File Max Size Epson
- código 314 Epson
- EcoTank 314 archivos adjuntos
- EcoTank 314 attached files
- El tamaño de los datos es mayor que el máximo admitido para archivos adjuntos
- Epson 314
- Epson error code 314
- Epson ET-5800 314
- Epson ET-5805 314
- Epson L6550 314
- Error 314 Ariston
- Lydos Hybrid 314
- Nuos Plus 314
- ON/OFF repetido 314 Ariston
- Ta máx arch ad Epson
- The data size exceeds the maximum size for attached files
What it means
In the official Spanish/multilingual instruction manuals for the Ariston Nuos Plus S2 Wi-Fi (80L, 110L and 150L) and Ariston Lydos Hybrid Wi-Fi (80L and 100L) heat pump water heaters, error code 314 is listed as repeated ON/OFF (ON/OFF repetido / ON/OFF repetidos under electronics circuit codes). While code 314 is active, both the electric heating element and the heat pump are set to OFF, halting all water heating to protect the compressor and control electronics. Other Ariston models may handle rapid switching differently. On its own, code 314 never proves that the ON/OFF key, compressor or main board is faulty.
Warnings and stop conditions
- Mediumeditorial warning
While error 314 is active, both the electric heating element and the heat pump remain OFF; pressing ON/OFF again before 15 minutes have passed will keep hot water production stopped.
Evidence: Ariston Nuos Plus S2 Wi-Fi, calentador de agua con bomba de calor: instrucciones para la instalación, el uso y el mantenimiento · Ariston Lydos Hybrid Wi-Fi, calentador de agua eléctrico híbrido: instrucciones de uso y mantenimiento 420010890100
- Higheditorial warning
All power supply circuits must be disconnected before accessing any internal terminals, and maintenance or repairs may only be carried out by qualified personnel.
Evidence: Ariston Nuos Plus S2 Wi-Fi, calentador de agua con bomba de calor: instrucciones para la instalación, el uso y el mantenimiento · Ariston Lydos Hybrid Wi-Fi, calentador de agua eléctrico híbrido: instrucciones de uso y mantenimiento 420010890100
Symptoms and causes
Probable causes · in order
- Repeated pressing of the ON/OFF button within a short periodCommon
Switching the water heater off and on several times in quick succession via the ON/OFF button triggers the protective 314 electronic lockout.
Evidence: Ariston Nuos Plus S2 Wi-Fi, calentador de agua con bomba de calor: instrucciones para la instalación, el uso y el mantenimiento · Ariston Lydos Hybrid Wi-Fi, calentador de agua eléctrico híbrido: instrucciones de uso y mantenimiento 420010890100
- Multiple reset attempts in a row while trying to clear another errorPossible
Pressing ON/OFF repeatedly to clear a previous fault code causes the electronics to lock out both the heat pump and the electric element for at least 15 minutes.
Evidence: Ariston Nuos Plus S2 Wi-Fi, calentador de agua con bomba de calor: instrucciones para la instalación, el uso y el mantenimiento · Ariston Lydos Hybrid Wi-Fi, calentador de agua eléctrico híbrido: instrucciones de uso y mantenimiento 420010890100
- False button signal on the user interface panel or main board connectionLess common
If code 314 appears without anyone touching the controls, a loose connection between the user interface and the main board or a faulty keypad may register repeated presses.
Evidence: Ariston Nuos Plus S2 Wi-Fi, calentador de agua con bomba de calor: instrucciones para la instalación, el uso y el mantenimiento · Ariston Lydos Hybrid Wi-Fi, calentador de agua eléctrico híbrido: instrucciones de uso y mantenimiento 420010890100
Virtual technician
Does 314 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
Was this entry useful?