BoilerBuddy · Alpha E-Tec 28/33 · source-backed fault codes
Alpha E-Tec 28/33 fault codes
These confirmed guides apply to the Alpha E-Tec 28 and 33. Check the boiler model before using range-specific guidance, then choose the exact numeric code shown on the display.
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Verified boiler fault-code guides
Choose a supported model and code to read the catalogue entry and its source documents.
Alpha · E-Tec 28/33
- Alpha 75Return/flow sensor fault — possible failure of one or both sensors.
- Alpha 76Return/flow sensor fault — possible failure of one or both sensors.
- Alpha 10Code 10 indicates that primary system pressure is low.
- Alpha 01Code 01 indicates ignition failure.
- Alpha 02Overheat boiler lock out: overheat sensor has activated
- Alpha 05CH flow sensor fault: incorrect flow sensor resistance value
- Alpha 06DHW sensor fault: DHW sensor resistance value is incorrect
- Alpha 16Fan fault: fan wiring fault or fan faulty
- Alpha 03High flue temperature: flue sensor intervention (flue temperature too high)
- Alpha 04Gas valve electrical connection fault: gas valve wiring circuit fault detected
- Alpha 20Flame sensing fault: false flame detection, flame detected but gas valve is not open
- Alpha 08Maximum number of resets reached (5).
- Alpha 12DHW inlet sensor fault — optional DHW inlet sensor resistance out of range.
- Alpha 15Incorrect configuration — inconsistency between settings and PCB signals.
- Alpha 22PCB fault — PCB software error.
- Alpha 23Return sensor fault — return sensor resistance out of range.
- Alpha 24Control panel button fault — button stuck in the on position.
- Alpha 25PCB fault — software error.
- Alpha 27Primary circuit overheat — insufficient circulation in primary circuit causing overheating.
- Alpha 31Loss of communication with external Alpha Climatic control.
- Alpha 37Low supply voltage — insufficient supply voltage to operate boiler.
- Alpha 51Climatic RF communication fault.
- Alpha 60Pump fault — pump stuck or electrical pump fault.
- Alpha SrService reminder countdown (0–36 months).