What does the Glow-worm F.83 fault code mean?

Your boiler is locking out because it cannot detect the water heating up properly when the burners turn on, which usually points to a sensor or circulation problem.

How much does it cost to fix Glow-worm error code F.83?

Typical repair cost for the Glow-worm F.83 fault is £150-£250 including labour.

Glow-worm F.83 Fault Code: What It Means & How to Fix It

What the manual says

Manufacturer manual

Fault: Flow and/or return temperature sensor temperature change - When the burner starts, no temperature change or an excessively small temperature change is registered on the flow or return temperature sensor

From this model's manual

Verified against the Glow Worm/Glow Worm Energy 35 Store Installation And Maintenance Instruc installation & service manual.

Engineer required

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

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Boiler cover options

Avoid the next call-out bill

A cover plan would handle faults like F.83: no call-out fees, no surprise bills.

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Related fault codes

F.75View →F.22View →

All 72 fault codes on the Energy 35 Store

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

Your boiler is locking out because it cannot detect the water heating up properly when the burners turn on, which usually points to a sensor or circulation problem.

What the manual says

Engineer required

Avoid the next call-out bill

Related fault codes

All 72 fault codes on the Energy 35 Store

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