What does the Ideal FU fault code mean?

Your boiler has detected that heat is building up too quickly and cannot circulate around your home, likely due to a blockage or a pump failure.

How much does it cost to fix Ideal error code FU?

Typical repair cost for the Ideal FU fault is £150-£350 including labour.

Check that the main isolation valves underneath the boiler are fully open

Manufacturer manual

DIFF GREATER THAN 50ºC. CHECK ISOLATION VALVES ARE OPEN, CHECK PUMP, CHECK RAD VALVES OPEN, CHECK SYSTEM BLOCKAGES.

From this model's manual

Verified against the Ideal/Ideal G101 Ideal Independent System S18 4175070 installation & service manual.

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

Boiler cover options

A cover plan would handle faults like FU: no call-out fees, no surprise bills.

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