BoilerFaultCodesThe 6 most common faults
Your boiler has temporarily stopped working because the water pressure inside the heating system has dropped too low.
Locate the filling loop valves underneath your boiler or near the hot water cylinder.Open the valves slowly to let water into the system until the pressure gauge on the front of the boiler reads between 1.0 and 1.5 bar.Close both valves firmly and check the gauge holds steady, then reset the boiler if necessary.
Your boiler has lost the ability to monitor its own heating temperature because a key internal sensor has failed or disconnected.
Full guide for ALL 05Your boiler has stopped working because it cannot detect a flame to safely light itself.
Full guide for ALL 06Your boiler has stopped working because the water pressure inside the system has risen above the safe limit of 2.8 bar.
Locate a radiator in your home that has a bleed valve.Use a radiator bleed key to open the valve slightly and let water out into a cloth or container.Watch the boiler's pressure gauge drop until it sits in the normal green zone (around 1.0 to 1.5 bar), then firmly close the bleed valve.
Your boiler has temporarily stopped because it cannot detect water flowing through the system properly.
Full guide for ALL 09Your boiler has detected an issue with the internal fan speed, which has caused it to safely shut down to prevent unsafe operation.
Full guide for ALL 15on the Sime Murelle Elite HE 35 T ErP System
Based on parts cited in our fault code database. Your engineer will confirm what's actually needed after diagnosis.
Call a Gas Safe engineer if…
- You can smell gas or see signs of a leak
- The Sime shows an Emergency or High severity code
- The boiler keeps locking out after repeated resets
- You've tried the DIY checks and the fault hasn't cleared
- There's visible water leaking from the boiler
- The flame is yellow or orange instead of blue
Avoid the next call-out bill
Monthly cover means no unexpected bills when your boiler breaks down.
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