High
52 on Ideal Classic FF

Your boiler is failing to keep its small pilot flame burning, which means it cannot fire up to provide heating or hot water.

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

PILOT WILL NOT STAY LIT WHEN THE GAS VALVE BUTTON IS RELEASED

From this model's manual
Verified against the Ideal Classic Ff 330 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.

What causes this fault?

This fault occurs when the boiler's safety monitoring system fails to detect a constant pilot flame, causing it to shut down gas flow for safety. The most common reason is a worn-out thermocouple or a faulty overheat thermostat that is incorrectly sensing that the boiler is getting too hot.

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 52: 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 guides you might find useful

Pilot light keeps going out

Older boilers — thermocouple, draught, gas supply.

Read →

No hot water but heating works

Almost always a stuck diverter valve on combis.

Read →

Boiler won't turn on — 9-step checklist

Work through these before the call-out.

Read →