High
01 on Vokera Synergy E

Your boiler has tried to light but cannot find a flame, which is often caused by a temporary interruption in your gas supply or a blocked flue.

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

Gas supply problem; Gas line requires purging; Reversed polarity; Broken, internal flue joint. Appears when the burner has failed to ignite, or the flame supervision system has failed to detect a flame.

From this model's manual
Verified against the Vokera Synergy E installation & service manual, page 53.
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 boiler's control system attempts to light the burner but fails to detect a steady flame after several attempts. The most common reasons include a temporary interruption in the gas supply, a dirty ignition electrode that can no longer create a spark, or an issue with the air supply preventing successful combustion.

This issue can be more common during the first cold snap of winter when gas components that have been idle all summer are suddenly put under high demand.

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.

Find a Gas Safe engineer
Search the official register →

Avoid the next call-out bill

A cover plan would handle faults like 01: no call-out fees, no surprise bills.

Approved partner
Domestic Appliance Guard
Unlimited call-outs, 24/7 helpline, no price-hike promise
Get a quote →

Affiliate links. We may earn a commission at no extra cost to you.

Related fault codes

Related guides you might find useful