E7 Boiler Fault Code: What It Means on Every Brand

The E7 fault code appears on 3 boiler brands — Alpha, Protherm and Remeha — and on all of them it points to the same kind of problem. The details still differ by brand (thresholds, sub-codes, reset procedure), so use the table below to jump to the page for your boiler.

Lockout — engineer likely 3 brands use this code

Which brand is your boiler?

The brand is printed on the front casing. Tap your brand for the full causes, fixes and repair costs.

Brand	What E7 means	Severity	DIY?
AAlpha	The E7 fault code on Alpha boilers most commonly indicates a temperature sensor (NTC thermistor) fault or an overheat lockout condition. Full guide →	Lockout — engineer likely	No
PProtherm	The E7 code (sometimes displayed as Eb on certain Protherm models) indicates that the boiler's control board has attempted to fire the burner but failed to detect a successful ignition. Full guide →	Lockout — engineer likely	No
RRemeha	The E7 fault code on Remeha boilers is a multi-purpose alert that can signal one of several underlying problems depending on your specific model. Full guide →	Lockout — engineer likely	Some checks

E7 brand by brand

Alpha E7

The E7 fault code on Alpha boilers most commonly indicates a temperature sensor (NTC thermistor) fault or an overheat lockout condition. The boiler's control board has detected an abnormal temperature reading — either because a thermistor is sending incorrect resistance data, or because water temperature has climbed beyond safe operating limits — and has shut the boiler down as a precaution. Alpha fault codes can vary slightly between model ranges (Intec, E-Tec, E-Tec Plus, Evoke, Eco, and Protec Plus among others), so it is always worth cross-referencing your specific model's manual to confirm the exact meaning on your unit. That said, a sensor or overheating-related lockout is the most consistent interpretation of E7 across Alpha's numbering pattern.

Causes, fixes & costs for Alpha E7 → · All Alpha codes

Protherm E7

The E7 code (sometimes displayed as Eb on certain Protherm models) indicates that the boiler's control board has attempted to fire the burner but failed to detect a successful ignition. As a safety measure, the boiler locks out rather than continuing to try. The electronic control unit continuously monitors signals from key sensors, and when the ignition or flame signal is absent or falls outside the expected range, E7 is triggered. This is essentially the boiler telling you: 'I tried to light the burner, but something stopped it from working correctly.'

Causes, fixes & costs for Protherm E7 → · All Protherm codes

Remeha E7

The E7 fault code on Remeha boilers is a multi-purpose alert that can signal one of several underlying problems depending on your specific model. On the Avanta range it most commonly points to a loss of water flow — either because system pressure has dropped too low or the circulation pump has stopped working. On the Avanta Plus, E7 is also associated with an air pressure switch fault, meaning the boiler cannot confirm that combustion air is moving correctly through the flue. Some model variants additionally use E7 to indicate a flame detection failure, where the boiler loses its flame signal during a heating or hot water cycle and locks out as a safety measure. Because the code covers more than one fault type, the practical first step is always to note which symptoms accompany the code — cold radiators, low pressure, or repeated lockouts during hot water use — before working through the checks below.

Causes, fixes & costs for Remeha E7 → · All Remeha codes

Frequently asked questions

Is the E7 fault code the same on every boiler?

Broadly, yes — on Alpha, Protherm and Remeha the E7 code points to the same class of fault, and the recommended response is similar. Model-specific details such as sub-codes and reset procedures still vary, so follow the page for your own brand.

Can I fix a E7 fault myself?

On some brands there are safe homeowner checks first — typically system pressure, the condensate pipe in cold weather, and a single reset. The underlying repair usually needs a registered engineer. Never open the boiler casing yourself.

Who should I call about a E7 fault?

For gas boilers, a Gas Safe registered engineer — it is a legal requirement for any work on the appliance. If you smell gas at any point, leave the property and call the National Gas Emergency line on 0800 111 999.

General guidance only — not a substitute for professional advice, and not certified by a registered engineer. Any work on a gas appliance must be carried out by a Gas Safe registered engineer. If you smell gas, call 0800 111 999.