High
Lights Flash Off Flash on Potterton Promax 15/2 HE Plus

Your boiler is not receiving enough electricity from your home's power supply to run safely and consistently.

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

Low Electrical Supply. Incoming Voltage less than 180V. Check System Controls & System Wiring. Otherwise contact Electricity Provider.

From this model's manual
Verified against the Potterton Boiler Promax 30 He Plus installation & service manual.
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.

Find a Gas Safe engineer
Search the official register →
Boiler cover options

Avoid the next call-out bill

A cover plan would handle faults like Lights Flash Off Flash: 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

E119View →E133View →

All 24 fault codes on the Promax 15/2 HE Plus

Seeing a different code? Every code this model can display, in one place.

E06FAN LOCKOUTFlash Flash OnFlash Off FlashFlash Off OnFlash On FlashFlash On OnLights Flash Flash OnLights Flash Off OnLights Flash On FlashLights Flash On OnLights Off Off OffLights On Flash FlashLights On Off FlashLights On On FlashOn Flash FlashOn Flash OnOn Off FlashOn Off OnOn On FlashOn On OnOVERHEAT LOCKOUTTHERMISTOR

Related guides you might find useful

Boiler won't turn on — 9-step checklist

Work through these before the call-out.

Read →

Yellow or orange flame — CO safety

Safety-critical — turn off, read this.

Read →

When to replace your boiler

7 signs repair isn't worth it anymore.

Read →