b Low
Your boiler is simply showing you a status update to confirm the fan is spinning at its normal operating speed.
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.
Technical description: Speed mode (half digits) - Displaying fan speed (e.g. 45 = 4500 rpm)
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 b — no call-out fees, no surprises.
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Remeha Quinta 30 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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