Sime Murelle Revolution 30 Fault codes & diagnostics

48 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.

Combi Natural Gas 2019-present
GC Number 47-283-87
Download the Sime Murelle Revolution 30 manual The official installation & service manual (PDF) — the exact document these fault codes were verified against. PDF

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Severity at a glance

Each cell = one fault code. Hover to identify.
3 Emergency 38 High 7 Medium

All 48 documented codes

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ALL 02

Your boiler has stopped working because the water pressure inside the heating system has dropped too low.

High DIY-safe £80-120

What to check first

  1. Locate the filling loop (a flexible metal hose) connected to the underside of the boiler.
  2. Open the valves on the filling loop slowly to let water into the system.
  3. Watch the pressure gauge on the front of the boiler until the needle reaches 1.5 bar, then securely close the valves.

Parts commonly replaced

  • Filling loop
  • Pressure relief valve
  • Pressure sensor

Related codes

ALL 03

Your boiler has detected that the water pressure inside the heating system has risen too high, which may cause it to stop working to protect the internal components.

Medium DIY-safe £80-120

What to check first

  1. Locate a radiator in your home, preferably one upstairs.
  2. Place a cloth or small container under the radiator bleed valve.
  3. Open the bleed valve slightly using a radiator key until water starts to trickle out.
  4. Allow a small amount of water to drain until the pressure gauge on your boiler drops to the green zone (typically 1.0 to 1.5 bar).
  5. Close the valve tightly and check that the boiler restarts.

Parts commonly replaced

  • Pressure Relief Valve
  • Expansion Vessel
  • Pressure Sensor

Related codes

ALL 04

Your boiler has lost the ability to measure the temperature of your hot water, which means it may struggle to heat your taps or shower correctly.

Medium Engineer only £120-200

Parts commonly replaced

  • Domestic Hot Water NTC Sensor

Related codes

ALL 05

Your boiler has stopped working because it is unable to accurately measure the temperature of the water being sent to your radiators or taps.

High Engineer only £120-200

Parts commonly replaced

  • Delivery NTC sensor
  • Wiring harness

Related codes

ALL 06

Your boiler is trying to start but cannot detect a flame, so it has safely shut down to prevent gas from building up.

High Engineer only £120-250

Parts commonly replaced

  • Ignition electrode
  • Ionisation probe
  • Gas valve

Related codes

ALL 07

Your boiler has detected that it is getting too hot and has automatically shut down to prevent damage or dangerous overheating.

High Engineer only £120-250

Parts commonly replaced

  • Safety thermostat
  • Central heating pump
  • System filter

Related codes

ALL 08

Your boiler is failing to detect the flame needed to heat your home, so it has safely shut itself down to prevent gas from building up.

High Engineer only £120-250

Parts commonly replaced

  • Flame rectification probe
  • Ignition electrode
  • PCB

Related codes

ALL 09

Your boiler has detected that water is not flowing around your heating system properly, so it has shut down to prevent damage.

High DIY-safe £120-250

What to check first

  1. Check your radiator valves are fully open to allow water flow
  2. Ensure the system pressure gauge is between 1 and 1.5 bar
  3. If the pressure is low, top it up using your boiler's filling loop
  4. Check if your central heating pump is set to a higher speed if adjustable

Parts commonly replaced

  • Central heating pump
  • Flow switch
  • System filter

Related codes

ALL 10

Your boiler's control system is struggling to read a temperature sensor, which is causing it to stop operating to ensure safety.

High Engineer only £120-220

Parts commonly replaced

  • Auxiliary temperature sensor
  • Wiring harness

Related codes

ALL 11

Your boiler has lost the electrical connection to the valve that controls the flow of gas, meaning it cannot safely ignite or heat your home.

High Engineer only £120-250

Parts commonly replaced

  • Gas valve wiring harness
  • Gas valve assembly
  • PCB

Related codes

Showing 11–20 of 48
ALL 12

Your boiler's internal settings do not match the way it has been installed, meaning it cannot determine how to safely vent its exhaust fumes.

High Engineer only £90-180

Parts commonly replaced

  • Main Control Board (PCB)
  • Configuration Plug/Jumper

Related codes

ALL 13

Your boiler has detected that the temperature of the exhaust gases leaving the system is too high, so it has automatically shut down for safety reasons.

Emergency Engineer only £150-300

Parts commonly replaced

  • Exhaust temperature sensor
  • Flue gas probe
  • PCB

Related codes

ALL 14

Your boiler has detected an issue with the sensor that monitors the temperature of the exhaust fumes, meaning it has shut down as a precaution to ensure safe operation.

High Engineer only £150-250

Parts commonly replaced

  • Flue gas temperature sensor
  • Wiring harness

Related codes

ALL 15

Your boiler has detected that a wire connected to the air-movement fan is loose or unplugged, meaning the system cannot safely vent exhaust gases.

High Engineer only £120-220

Parts commonly replaced

  • Fan wiring harness
  • Fan assembly
  • PCB

Related codes

ALL 18

Your boiler has detected that the internal drain pipe is blocked, preventing wastewater from exiting the system safely.

High Engineer only £120-220

Parts commonly replaced

  • Condensate trap
  • Condensate siphon
  • Drain pipework

Related codes

ALL 28

Your boiler has attempted to restart itself too many times following previous faults and has now locked itself out for safety.

High Engineer only £120-250

Parts commonly replaced

  • Ignition electrode
  • Gas valve
  • PCB
  • Flame sensor

Related codes

ALL 30

Your boiler is currently unable to read the temperature of the water returning to it, so it has stopped running to prevent any damage.

High Engineer only £150-250

Parts commonly replaced

  • Return NTC sensor
  • Wiring harness

Related codes

ALL 37

Your boiler is struggling because the electricity supply coming into your home is dipping below the level required to keep the system running safely.

High Engineer only £100-250

Parts commonly replaced

  • PCB
  • Wiring harness
  • Voltage regulator

Related codes

ALL 40

Your boiler is struggling to sync with the electricity supply because the incoming power frequency is unstable or outside of the normal range.

High Engineer only £120-250

Parts commonly replaced

  • Printed Circuit Board (PCB)
  • Electrical wiring harness

Related codes

ALL 41

Your boiler has attempted to ignite several times but has failed to keep the flame running, so it has safely shut itself down to prevent gas from building up.

High Engineer only £120-250

Parts commonly replaced

  • Ignition electrode
  • Gas valve
  • Flame rectification probe

Related codes

Showing 21–30 of 48
ALL 42

Your boiler's control panel is struggling to register your button presses because one of the buttons is stuck or the electronic interface is malfunctioning.

Medium Engineer only £120-250

Parts commonly replaced

  • Interface board
  • Control panel fascia

Related codes

ALL 43

Your boiler has lost the digital connection between its main controls and the heating system, meaning it doesn't know when to turn on or off.

High Engineer only £120-250

Parts commonly replaced

  • PCB
  • OpenTherm interface cable
  • External smart thermostat

Related codes

ALL 44

Your boiler is failing to light because it has detected an issue with the internal timing of its gas valve, meaning it cannot safely start the burner.

High Engineer only £150-300

Parts commonly replaced

  • Gas valve
  • PCB (Printed Circuit Board)
  • Wiring harness

Related codes

ALL 62

Your boiler is signalling that it needs to perform an automated internal setup process to ensure it is burning fuel safely and efficiently.

Medium Engineer only £90-160
ALL 72

Your boiler is struggling to accurately measure the temperature of the water flowing out of it because the temperature sensor has likely become loose or shifted from its correct position.

Medium Engineer only £120-220

Parts commonly replaced

  • Delivery NTC sensor
  • Sensor retaining clip

Related codes

ALL 77

Your boiler has detected an electrical issue with the gas control system that prevents it from firing safely.

High Engineer only £150-350

Parts commonly replaced

  • Gas valve
  • PCB (Main control board)
  • Wiring harness

Related codes

ALL 78

Your boiler has detected an electrical issue with the gas control valve, preventing it from operating safely.

High Engineer only £180-350

Parts commonly replaced

  • Gas valve
  • PCB

Related codes

ALL 79

Your boiler's gas valve is failing to draw the correct electrical current, which means the system cannot safely regulate the fuel supply to produce heat.

High Engineer only £250-450

Parts commonly replaced

  • Gas Valve
  • Wiring Harness
  • PCB

Related codes

ALL 80

Your boiler has detected an electrical communication problem with one of its internal control components, which is preventing the system from operating correctly.

High Engineer only £150-250

Parts commonly replaced

  • Wiring harness
  • Gas valve
  • Main control PCB

Related codes

ALL 82

Your boiler has detected multiple failed attempts to light the flame or maintain stable burning, so it has locked itself for safety to prevent gas buildup.

Emergency Engineer only £150-350

Parts commonly replaced

  • Ignition electrode
  • Gas valve
  • Flame ionization probe

Related codes

Showing 31–40 of 48
ALL 84

Your boiler is struggling to get enough gas from the supply to run properly, so it has stopped working to protect itself.

High Engineer only £120-250

Parts commonly replaced

  • Gas valve
  • Gas regulator
  • Gas meter components

Related codes

ALL 88

Your boiler's main control computer is experiencing an internal electronic fault, which has triggered a safety shutdown to prevent further damage.

High Engineer only £250-450

Parts commonly replaced

  • Main printed circuit board (PCB)
  • Control unit

Related codes

ALL 89

Your boiler is having trouble managing the air and gas mixture required for safe and efficient burning.

High Engineer only £150-300

Parts commonly replaced

  • Ionisation probe
  • Gas valve
  • Flue assembly

Related codes

ALL 90

Your boiler is struggling to achieve the correct air and gas mixture required for safe and efficient burning.

High Engineer only £150-300

Parts commonly replaced

  • Gas valve
  • Flue seal
  • Fan assembly
  • Air pressure switch

Related codes

ALL 92

Your boiler's internal computer has detected too much air in the system while trying to run at a low power setting and has locked itself out to prevent damage.

High Engineer only £120-250

Parts commonly replaced

  • Gas valve
  • Flue gas analysis sensor
  • Ignition electrode

Related codes

ALL 93

Your boiler is struggling to achieve the correct air and gas mixture required for safe and efficient burning.

High Engineer only £150-350

Parts commonly replaced

  • Gas valve
  • Flue assembly
  • Fan assembly
  • Air pressure switch

Related codes

ALL 95

Your boiler is struggling to keep a steady flame, causing it to momentarily lose the signal that the fire is lit and shut down as a safety precaution.

High Engineer only £150-300

Parts commonly replaced

  • Flame rectification electrode
  • Ignition lead
  • PCB

Related codes

ALL 96

Your boiler has detected a blockage in the exhaust system and has safely shut down to prevent the release of harmful combustion gases into your home.

Emergency Engineer only £120-250

Parts commonly replaced

  • Flue assembly
  • Fan unit
  • Air pressure switch
  • Condensate trap

Related codes

ALL 98

Your boiler's computer is failing to start up correctly, preventing it from functioning at all.

High Engineer only £250-450

Parts commonly replaced

  • Main Control Board (PCB)

Related codes

ALL 99

Your boiler's main control unit is experiencing a general electronic fault, preventing it from operating safely or reliably.

High Engineer only £250-450

Parts commonly replaced

  • Main PCB
  • Wiring harness

Related codes

Showing 41–48 of 48
P 02

Your boiler has detected that the water pressure inside the system is too high, which prevents it from operating safely.

High DIY-safe £80-150

What to check first

  1. Locate a radiator in your home that is easily accessible.
  2. Place a cloth or small container under the radiator bleed valve.
  3. Open the bleed valve slightly to release air and a small amount of water until the boiler's pressure gauge drops back into the green zone (typically 1.0 to 1.5 bar).
  4. Close the valve tightly once the pressure is normal.

Parts commonly replaced

  • Pressure relief valve
  • Pressure gauge
  • Expansion vessel

Related codes

P 04

Your boiler has stopped working because the water pressure inside the heating system has dropped too low.

High DIY-safe

What to check first

  1. Locate the filling loop, which is a silver braided hose with one or two valves connecting your mains water to your heating pipes.
  2. Open the valve(s) slowly to allow mains water into the system until the pressure gauge on the front of the boiler reads between 1.0 and 1.5 bar.
  3. Close the valve(s) tightly and check that the error code has cleared.

Parts commonly replaced

  • Pressure relief valve
  • Pressure sensor
  • Expansion vessel

Related codes

P 12

Your boiler has detected that the water inside the system is close to freezing and has paused operation to protect itself from damage.

Medium Engineer only £100-250

Parts commonly replaced

  • NTC Temperature sensor
  • PCB main control board
  • Wiring harness

Related codes

P 15

Your boiler has detected that the water inside the system has become dangerously hot and has shut itself down to prevent damage.

High Engineer only £120-250

Parts commonly replaced

  • NTC sensor
  • Pump
  • Primary heat exchanger

Related codes

P 32

Your boiler has detected an issue with one of its internal temperature sensors, preventing it from operating safely.

High Engineer only £120-250

Parts commonly replaced

  • NTC temperature sensor
  • Wiring harness
  • PCB

Related codes

P 33

Your boiler is having trouble communicating with the internal temperature sensor for its battery system, which prevents it from managing energy storage correctly.

Medium Engineer only £150-250

Parts commonly replaced

  • Battery temperature sensor
  • Wiring harness
  • Main PCB

Related codes

P 34

Your boiler is struggling to accurately measure the temperature of the water coming into the system, which prevents it from heating your home properly.

High Engineer only £120-220

Parts commonly replaced

  • Inlet water temperature sensor
  • Wiring harness

Related codes

P 35

Your boiler has lost the ability to accurately measure the temperature of the water flowing through the system, so it has shut down to prevent overheating.

High Engineer only £120-£200

Parts commonly replaced

  • NTC Temperature Sensor
  • Wiring harness

Related codes

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