If your Baxi Combi 2 or System 2 is showing E.01.17, Baxi defines the code as “No water circulation (permanent)”. In plain English, the boiler has detected that heating water is not moving around the system as expected and the condition has persisted long enough to be treated as a permanent fault. The boiler may stop operating to protect itself and the heating system.
This is different from a brief delay while the boiler starts. E.01.17 indicates a circulation problem that has not cleared. It needs attention from a qualified heating engineer, especially if the code returns after the single reset permitted by the instructions for your exact model.
What E.01.17 means
A central-heating system relies on water circulating between the boiler and the rest of the system. In a combi installation, that circulation supports central heating and the boiler also produces hot water on demand. In a system-boiler installation, the boiler commonly works with a separate hot-water cylinder as well as radiators.
The E.01.17 message does not tell a homeowner which individual part needs replacing. It reports the result the boiler has detected: no water circulation, and the condition is permanent rather than momentary. Several technical conditions can lead to poor or absent circulation, so the code should not be used as a parts list or a reason to open the casing.
What you may notice at home
The display may show E.01.17 while the boiler stops producing useful heat. Radiators can remain cold, warm only briefly or heat unevenly. On a System 2 installation, the hot-water cylinder may not be heated as expected because the boiler is not moving heat through the primary circuit. A combi household may notice that heating is unavailable and hot-water performance is disrupted.
You may also have noticed unusual water noises before the lockout, or a pattern where the boiler starts and then stops. These observations are useful to an engineer, but they do not prove the cause. Note whether the problem affects heating, hot water or both, when it began, and whether any recent work has been carried out on the heating system.
Safe checks you can make
Keep the checks simple and external. Do not remove the boiler case, loosen fittings, bleed internal components or try to work on pumps, valves, wiring or controls.
- Read the full display. Photograph E.01.17 and any other message shown before it changes.
- Check the system pressure shown on the boiler. Compare it with the normal range stated in the user guide for your exact model. Do not guess a target pressure or add water unless you understand the manufacturer’s filling instructions and can follow them safely.
- Check visible controls. Make sure the programmer or thermostat is asking for heat and that the boiler’s external power supply has not been switched off accidentally.
- Look for obvious external leaks. Without touching the boiler or removing panels, check for water around visible radiators, pipework and the boiler area. If there is an active leak, switch the heating off and arrange help.
- Record what the system was doing. Note whether E.01.17 appeared during heating, hot-water demand or cylinder heating.
Should you reset the boiler?
Use only the reset procedure described in the Baxi user guide for your exact boiler. One reset can be reasonable if the guide permits it and there is no smell of gas, sign of overheating, active leak or other safety concern. Do not keep resetting a boiler that returns to E.01.17. Repeated resets do not restore reliable circulation and can hide the pattern an engineer needs to assess.
If the boiler restarts, watch it from outside the casing. If the code returns, stop using reset as a workaround and book a repair. A fault described as permanent should be treated as requiring professional attention even if it clears temporarily.
What not to do
- Do not remove the boiler casing or touch internal components.
- Do not try to free, turn or electrically test the pump.
- Do not adjust internal valves, wiring or circuit-board connections.
- Do not repeatedly add water to compensate for falling pressure.
- Do not run the boiler through repeated on-off cycles to force circulation.
Internal boiler work and gas-related work must be carried out by a suitably qualified Gas Safe registered engineer. A circulation fault may also involve the wider heating system, so give the engineer a clear account of which rooms, radiators and hot-water functions were affected.
When to stop and seek urgent help
If you smell gas, turn off the gas at the meter if it is safe to do so, open doors and windows, avoid electrical switches and naked flames, leave the property and contact the National Gas Emergency Service on 0800 111 999. If a carbon monoxide alarm sounds, or anyone has symptoms such as headache, dizziness, nausea, breathlessness or confusion, move into fresh air, seek medical advice and arrange an urgent safety check.
For E.01.17 without those emergency signs, leave the boiler off if it is leaking, making alarming noises or repeatedly locking out. Arrange a professional repair rather than attempting internal checks.
What to tell the engineer
Provide the exact code, the boiler model, a photograph of the display and the system pressure shown when the fault occurred. Say whether heating, hot water or both were affected, whether the fault followed system work, and whether any visible leak or pressure change was noticed. This gives the engineer useful context without you needing to investigate inside the appliance.
Quick answers
What does Baxi E.01.17 mean?
Baxi lists E.01.17 as “No water circulation (permanent)” for its current Combi & System 2 fault-code group.
Can I keep using the boiler?
Do not rely on a boiler that repeatedly shows E.01.17. If it is leaking, overheating, making alarming noises or returning to lockout, switch it off and arrange repair.
Will topping up the pressure fix it?
Not necessarily. Pressure is only one external observation, and E.01.17 does not identify a single cause. Follow the exact user guide and do not repeatedly add water.
Can I reset it?
Use only the exact-model instructions and do not keep resetting a recurring fault. A returning E.01.17 code needs professional attention.
Need the boiler repaired?
Your boiler fault is fixed for the agreed price, subject to eligibility and terms.