BoilerFaultCodesWhat the manual says
Manufacturer manualALTERNATING 'H' '1' GO TO FRAME 90
What causes this fault?
This fault occurs when the water pressure inside your heating system drops below a safe level, causing the boiler to shut down to prevent damage. The most common reasons for this are a leak somewhere in your radiators or pipework, or simply that air has been bled from the system without being topped back up. It can also happen if a component like the expansion vessel has failed, causing water to be discharged through the safety pipe.
This issue is frequently seen in autumn when homeowners turn their heating back on for the first time or bleed their radiators to prepare for winter.
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 H1: no call-out fees, no surprise bills.
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All 19 fault codes on the Esprit HE
Seeing a different code? Every code this model can display, in one place.