Your boiler is staying in a cooling-down mode because the internal fan is running for longer than it should after heating your water.
This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.
Technical description: Hot–water fan over run
What causes this fault?
This issue occurs when the boiler's internal fan fails to stop spinning after the heating cycle has finished. It is usually caused by a faulty control board sending power to the fan when it shouldn't, or the fan itself failing to report that it has slowed down correctly. Because the boiler is waiting for the 'cool down' phase to end, it will stay in this standby mode and won't start the next time you need heat.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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 S.26 — no call-out fees, no surprises.
Affiliate links — we may earn a commission at no extra cost to you.
Vaillant Ecomax 613 2 E 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.
Affiliate links — we may earn a commission at no extra cost to you.