BoilerFaultCodesWhat the manual says
Manufacturer manualSafety temp. limiter in CH flow has tripped.
What causes this fault?
This fault occurs when the water temperature inside your boiler exceeds a safe limit, causing the safety sensor to shut the system down to prevent damage. The most common reasons are a failed internal pump that isn't moving water away quickly enough or a buildup of sludge and limescale that is restricting flow through the heat exchanger.
This fault is more common in the autumn when heating systems are switched back on after a long summer break, as internal pumps can seize up due to 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.
Avoid the next call-out bill
A cover plan would handle faults like E9: no call-out fees, no surprise bills.
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All 25 fault codes on the Greenstar 30HE
Seeing a different code? Every code this model can display, in one place.