High
1 8. on Remeha Quinta Ace 65

Your boiler has shut down because the water inside has become too hot, usually due to a lack of circulation or a blockage.

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

Max.water temperature: Flow temperature too high.

From this model's manual
Verified against the Remeha Quinta Ace 45 installation & service manual, page 36.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

What causes this fault?

This fault occurs when the water leaving the boiler exceeds its safe temperature limit, causing the system to shut down for safety. The most common cause is a failed internal pump that isn't moving water away from the burner quickly enough, or a significant blockage within the heat exchanger that is restricting flow. It can also be triggered by a faulty sensor that is incorrectly reporting the water temperature as being too high.

This issue is more frequent in autumn when heating systems are switched back on after a long summer break, as internal pump components are prone to seizing during periods of inactivity.

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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