- Boilers
- Gas boiler
E110
Baxi E110 on a gas boiler: overheat safety thermostat tripped
Risk level
High
Professional inspection is recommended.
Urgency
High
Quick answer
Baxi E110 means the overheat safety thermostat tripped, which Baxi links to a blocked pump or air in the heating circuit. Check the pressure, reset once by holding reset for 2 seconds and, if it returns, call the service centre.
Safety first
Stop and check this first
- Never bypass or disable a safety thermostat and do not chain resets: Baxi locks the boiler after 5 consecutive attempts. A boiler that overheats again and again needs the technician.
- If you smell gas: switch the boiler off, do not operate any electrical device or switch on lights, put out any flame, open the windows and leave; from outside, call your gas distributor's emergency number and the service centre. If you smell combustion fumes, switch the boiler off, ventilate and call the service centre.
Safe checks you can perform
- Pressure on the gauge
- One reset with the reset key
- Technician check of circulation
Leave these tasks to a qualified professional
- Do not attempt this professional task: Pump test and circuit bleeding
- Do not attempt this professional task: Safety thermostat check
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.
Pump test and circuit bleeding
What they doThe technician checks the pump's rotation and flow and bleeds air from the boiler and the system.
They must show youthe pump running and a stable flow temperature after the repair.
In writingwhether there was air, a stuck pump or both.
Safety thermostat check
What they doIf circulation is correct, the technician checks the safety thermostat and its connection before replacing it.
They must show youthe continuity check or reading that justifies the replacement.
In writingthe part replaced and why.
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.
Pressure on the gauge
- Who:
- you.
- How:
- with the system cold, read the boiler pressure gauge. Baxi asks for 1 to 1.5 bar when cold. Do not open the casing.
- Result that matters:
- whether the needle sits between 1 and 1.5 bar or below it.
- If it is below 1 bar:
- Baxi says to top up slowly with the boiler filling tap and then bleed the radiators; then see whether 110 comes back.
- If the pressure is correct:
- lack of water does not explain the code; do not add more.
- Evidence to keep:
- a dated photo of the gauge and a note each time you have to top up.
Evidence: Baxi Platinum Compact ECO, instrucciones de funcionamiento y mantenimiento para el usuario
One reset with the reset key
- Who:
- you.
- How:
- hold the reset key for at least 2 seconds, as Baxi says for 110. Baxi allows 5 consecutive resets, then you must wait 15 minutes. Do one, not five.
- Result that matters:
- whether the boiler heats again without 110 coming back.
- If it starts and heats normally:
- note the date; if it repeats, Baxi says to call the service centre.
- If 110 returns straight away:
- do not insist; the cause is still there and the boiler is protecting itself.
- Evidence to keep:
- a photo of the display with the code and the time of each reset.
Evidence: Baxi Platinum Compact ECO, instrucciones de funcionamiento y mantenimiento para el usuario
Technician check of circulation
- Who:
- official service technician.
- How:
- checks the pump turns and moves water, bleeds air from the circuit and checks the safety thermostat and its wiring.
- Result that matters:
- whether there is real flow through the heat exchanger and whether the thermostat cuts out at the right temperature.
- If the pump is stuck or there is air:
- that confirms the cause Baxi gives.
- If circulation is good:
- it points to the thermostat or its connection.
- Evidence to keep:
- a report with the finding and any part replaced.
The pump, heat exchanger and thermostat are inside the boiler, next to gas and mains voltage: only the technician touches them.
Evidence: Baxi Platinum Compact ECO, instrucciones de funcionamiento y mantenimiento para el usuario
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
- Baxi
- Product type
- Gas boiler
Known code variants
- 110
- Baxi 110
- Baxi E 110
- calentador Navien E110
- Error 110 Baxi
- Error Code 110
- Navien 110
- Navien E110
- Navien E110 air pressure
- Navien E110 presión de aire
- Navien error E110
- Platinum Compact 110
What it means
On the Platinum Compact ECO, code 110 is the overheat safety thermostat tripping. Baxi gives a blocked pump or air in the heating circuit as the probable causes: the water does not carry heat away from the heat exchanger and its temperature climbs to the safety limit. It is a lockout the user can reset, but Baxi limits consecutive resets. The code does not say whether the pump, air or the thermostat itself is at fault.
Warnings and stop conditions
- Higheditorial warning
Never bypass or disable a safety thermostat and do not chain resets: Baxi locks the boiler after 5 consecutive attempts. A boiler that overheats again and again needs the technician.
Evidence: Baxi Platinum Compact ECO, instrucciones de funcionamiento y mantenimiento para el usuario
- Criticalsource verified
If you smell gas: switch the boiler off, do not operate any electrical device or switch on lights, put out any flame, open the windows and leave; from outside, call your gas distributor's emergency number and the service centre. If you smell combustion fumes, switch the boiler off, ventilate and call the service centre.
Evidence: Baxi Platinum Compact ECO, instrucciones de funcionamiento y mantenimiento para el usuario
Symptoms and causes
Probable causes · in order
- Air in the heating circuitCommon
Baxi names it as a probable cause. It often comes with radiators cold at the top, gurgling or low pressure after bleeding.
Evidence: Baxi Platinum Compact ECO, instrucciones de funcionamiento y mantenimiento para el usuario
- Blocked circulation pumpCommon
Baxi names it alongside air. If pressure is correct, there is no air and the code returns, circulation is the suspect.
Evidence: Baxi Platinum Compact ECO, instrucciones de funcionamiento y mantenimiento para el usuario
- Safety thermostat or its wiringPossible
If circulation is good and the code returns from cold, the technician should check the thermostat itself and its connection.
Evidence: Baxi Platinum Compact ECO, instrucciones de funcionamiento y mantenimiento para el usuario
Virtual technician
Does E110 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
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