Low
139 on Alpha E-Tec Plus NX

Your boiler is currently performing a routine self-cleaning cycle to automatically remove trapped air from its internal system.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Deaeration in progress

Shared across the Alpha E-Tec Plus range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Wait for 10 to 15 minutes for the process to complete automaticallyEnsure your heating and hot water are not being used during this timeIf the code does not clear after 30 minutes, switch the boiler off at the fused spur and back on to reset it

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Related fault codes

138View →137View →

All 39 fault codes on the E-Tec Plus NX

Seeing a different code? Every code this model can display, in one place.

010203040506070810121516202324272931363738434445464748495160617075768388 8898138

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