High
1 flash red on Baxi 200 Heat

Your boiler is struggling to accurately measure the temperature of the water flowing through it, so it has shut down to prevent overheating.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

Sensor error: Bad connection to flow or return temperature sensor, Fault with flow or return temperature sensor(s), Low or no flow through boiler, Reverse flow through boiler

Shared across the Heat range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the 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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Related fault codes

E110View →E119View →

All 12 fault codes on the 200 Heat

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

1 flash green2 flashes green2 flashes red3 flashes green3 flashes red4 flashes green4 flashes red5 flashes green5 flashes red6 flashes green6 flashes red

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