BoilerFaultCodesYour boiler is struggling to move water through the system, which is usually caused by trapped air or a blockage in the pipes.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Poor circulation – try bleeding your radiators
What causes this fault?
This fault occurs when water cannot travel through the boiler’s internal heat exchanger quickly enough to carry heat away. The most common reasons are trapped air pockets creating a blockage, a buildup of sludge in the system, or the internal pump failing to spin correctly.
This issue is frequently seen in autumn when heating systems are switched back on after being idle all summer, which can cause internal pump components to seize.
DIY fix possible
Check that the boiler pressure is between 1 and 1.5 barTurn off the heating and use a radiator key to bleed air from all radiatorsEnsure all radiator valves (TRVs) are fully openReset the boiler using the reset button
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like E2 — no call-out fees, no surprises.
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Baxi Avanta is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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