High
E077 on Vokera Pinnacle System

Your boiler has lost connection with the device that tells it how to heat your low-temperature heating circuit, meaning it cannot communicate correctly to start the heating.

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

ABSENCE OF COMMUNICATION WITH LOW TEMPERATURE THERMOSTAT

From this model's manual
Verified against the Vokera Pinnacle System installation & service manual, page 7.
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

E070View →E078View →E079View →

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