Ravenheat Boiler Error Codes: Causes & Fixes

The most common Ravenheat boiler error codes UK homeowners and landlords see are 01 or 01E for ignition failure, E08 or 08E for low water pressure, E02 or 02E for pump circulation issues, E05 or 05E for fan problems, and various sensor codes such as E03 or E04. 

These codes help you identify the issue so you can restore heating and hot water safely and quickly.

Some can be fixed with a quick pressure top-up or reset, while others need a Gas Safe registered engineer. Understanding the code puts you in a stronger position and helps stop minor faults turning into larger repair bills. Many people find that having a boiler cover plan ready means they can get professional help without the worry of unexpected costs when a more serious fault shows up.

Ravenheat Boiler Error Codes: A Quick Overview

Here is a clear table of the Ravenheat boiler error codes you are most likely to encounter, with a short plain-English description of what each one usually means.

Codes can vary slightly by model, so always check your handbook if the display looks different. The table above covers the codes that appear most often across UK homes.

Ravenheat Boiler Error Codes: Causes & How to Fix

Below you will find dedicated sections for the main Ravenheat boiler error codes. Each one explains what the code means, the usual causes, and clear numbered steps you can take. Safety comes first: if you smell gas, turn the supply off at the meter if it is safe and call the National Gas Emergency Service on 0800 111 999. 

For any gas-related work or if a code returns after a reset, contact a Gas Safe registered engineer.

01 Or 01E Ignition Failure

The 01 or 01E error code means the boiler has attempted to light the burner but has not detected a flame. Heating and hot water will stop until the fault is cleared.

Common causes include a problem with the gas supply, a dirty or faulty ignition electrode, a failing gas valve, a fan that does not start, or issues with the ignition control board and cables. In cold weather a frozen condensate pipe can also stop the boiler lighting properly.

1. Check that other gas appliances in the home are working. If none are, contact your gas supplier.
2. Look outside for the condensate pipe and check whether it is frozen. Pour warm (not boiling) water along it to thaw any ice.
3. Press and hold the reset button on the boiler for a few seconds.
4. Listen for the fan and the spark attempting to light.
5. If the code returns after one or two resets, switch the boiler off and call a Gas Safe engineer. Do not keep resetting.

A frozen condensate pipe is a frequent winter cause and is often the quickest thing to check.

E02 Or 02E Pump Circulation Fault

The E02 or 02E fault code means water is not circulating properly through the heating system. Without good flow the boiler cannot heat the radiators or hot water safely.

Causes include a seized or failing pump, airlocks in the system, sludge or debris restricting flow, or closed valves.

1. Check and top up the system pressure to 1.0–1.5 bar if it is low.
2. Make sure all radiator valves (including lockshields) are open.
3. Bleed any radiators that feel cold at the top while the system is running.
4. Reset the boiler once.
5. If the code comes back, the pump may need freeing or replacing, or the system may need a power flush. These jobs require a qualified engineer.

Leaving a circulation fault unaddressed can lead to overheating or damage to the heat exchanger.

E08 Or 08E Low Water Pressure

The E08 or 08E code means the water pressure in the sealed heating system has dropped below the safe level. The boiler will not operate until the pressure is restored.

Causes include a small leak from a radiator, valve or pipe joint, natural pressure loss over time, or a problem with the expansion vessel.

1. Look at the pressure gauge on the boiler. It should sit between 1.0 and 1.5 bar when the system is cold.
2. Locate the filling loop (usually a flexible hose with two valves under or near the boiler).
3. Open both valves slowly until the gauge reaches about 1.2–1.5 bar.
4. Close both valves tightly.
5. Reset the boiler if needed and check that heating and hot water return.
6. Monitor the pressure over the next day or two. If it drops again there is likely a leak that needs professional attention.

Topping up is a straightforward job most homeowners can manage, but repeated drops should not be ignored.

E05 Or 05E Fan Fault

The E05 or 05E fault code indicates a problem with the fan or its signal. The fan is vital for safe combustion and removing flue gases.

Causes include a seized or failing fan motor, wiring issues, or a blocked fan housing.

Do not attempt to repair the fan yourself. Switch the boiler off and arrange for a Gas Safe engineer to diagnose and replace the fan if required. Running without a working fan is unsafe.

E03 Or 03E Flow Sensor Fault

The E03 or 03E error code means the central heating flow temperature sensor is damaged or giving an incorrect reading.

Causes are a failed sensor, damaged wiring or a poor connection.

This is not a DIY repair. Reset once if possible. If the code returns, an engineer will test and replace the sensor or repair the wiring.

E04 Or 04E DHW Sensor Fault

The E04 or 04E code relates to the domestic hot water temperature sensor. Hot water temperature control may be affected or the boiler may lock out.

Causes are similar to the flow sensor: a failed sensor or wiring problem. An engineer is needed to diagnose and replace the part.

E09 Or 09E Overheat

The E09 or 09E error code means the overheat sensor has detected that the water inside the boiler has got too hot and has shut it down.

Common reasons are a stuck or failing pump, restricted water flow, air in the system, or sludge build-up.

1. Turn the boiler off and allow it to cool completely (this can take 30–60 minutes).
2. Check system pressure and top up if needed.
3. Make sure all radiator valves are fully open.
4. Bleed any radiators that feel cold at the top.
5. Reset the boiler once it is cool.
6. If the code returns, do not keep using the boiler. Call a Gas Safe engineer to check the pump, flow and sensors.

E10 Or 10E High Water Pressure

The E10 or 10E fault code means the system pressure is too high.

Causes include overfilling, a failed expansion vessel, or a problem with the pressure relief valve.

1. Check the pressure gauge.
2. If pressure is above 2.0–2.5 bar when cold, carefully bleed a radiator to reduce it slightly (do not go below 1.0 bar).
3. Reset the boiler.
4. If pressure rises again quickly when the system heats up, an engineer needs to check or recharge the expansion vessel.

28 Low Water Or Pressure Switch Fault

The 28 code (common on CSI models) points to low water or a problem with the pressure switch or pump.

Causes include incorrect system pressure, a failing pump, or a faulty low water pressure switch.

1. Check and top up pressure to 1.0–1.5 bar.
2. Reset the boiler.
3. If the code returns, an engineer will need to test the switch and pump.

17 Fan Voltage Issue

The 17 error indicates a possible problem with the voltage supply to the fan.

Causes include wiring issues or a failing fan. This requires a Gas Safe engineer to diagnose safely.

F73 Or F74 Pressure Sensor Fault

The F73 or F74 fault code means there is a fault with the heating circuit pressure sensor.

Causes include a failed sensor, wiring problems or sludge affecting the reading. An engineer is required to test and replace the sensor if needed.

Having a boiler cover plan in place can make a real difference when codes like these appear. Instead of facing unexpected call-out and repair costs, you simply report the fault and a qualified engineer is arranged. For many UK homeowners and landlords this peace of mind, plus the included annual service, helps prevent small pressure or sensor issues from becoming expensive breakdowns.

How To Reset A Ravenheat Boiler Safely

Most Ravenheat models have a clearly marked reset button on the control panel. Press and hold it for a few seconds until the display clears or the boiler restarts. Only reset once or twice for the same code. If the fault returns, switch the boiler off and seek professional help. Continuous resetting can put extra strain on components and may hide a more serious problem.

When Ravenheat Boiler Error Codes Need an Engineer to Fix

A few Ravenheat faults can be dealt with through basic checks, such as restoring low system pressure for an E08 or 08E code, or checking for a frozen condensate pipe when the boiler will not ignite. However, if the problem points to a fault inside the boiler, it is best to stop troubleshooting and arrange for a Gas Safe registered engineer.

You should seek professional help if your Ravenheat boiler displays:

• A recurring 01 or 01E ignition fault, particularly after you have checked the gas supply and reset the boiler.
• An E02 or 02E circulation fault that returns after checking the system pressure and radiator valves, as the pump or another internal component may need attention.
• A fan-related code such as E05, 05E or 17, as the fan plays an essential role in safe combustion and the removal of flue gases.
• An overheating fault such as E09 or 09E, especially if the boiler continues to shut down after it has cooled and been reset.
• Persistent sensor or pressure faults, including E03, E04, F73 or F74, which may require component testing or replacement.
• Repeated pressure problems, including low pressure that keeps returning or high pressure that rises again after being reduced.

It is also important not to keep resetting a Ravenheat boiler that repeatedly locks out. If a fault continues to return, the error code is likely indicating an underlying issue that needs to be diagnosed rather than simply cleared. A qualified engineer can investigate the cause and carry out any necessary repairs safely.

How to Prevent Ravenheat Boiler Error Codes

• Monitor both low and high pressure readings: Check the boiler pressure occasionally when the system is cold and again if you notice it rising unusually when the heating is running. This can help identify developing issues before they lead to low-pressure faults such as E08 or high-pressure faults such as E10.
• Avoid repeatedly topping up the system: If your Ravenheat boiler regularly loses pressure, simply adding more water each time will not solve the underlying problem. Have recurring pressure loss investigated to identify leaks, expansion vessel faults or pressure relief valve issues.
• Keep radiator valves in their normal operating position: After decorating, replacing radiators or carrying out other work on the heating system, check that valves have not been left closed or partially closed, as restricted flow can contribute to pump and overheating faults.
• Address dirty system water before it affects circulation: Discoloured water, cold radiator sections or persistent circulation problems can indicate sludge or debris within the heating system. Having the system assessed and cleaned where necessary may help protect the pump and maintain proper water flow.
• Take unusual pump noises seriously: Humming, grinding or changes in the normal sound of the heating system may indicate that the pump is struggling. Investigating this early could help prevent circulation faults such as E02, 02E or Code 28.
• Reduce the risk of winter condensate problems: Before periods of freezing weather, check that the external condensate pipe is in good condition and appropriately protected against freezing where required. This can help reduce the risk of ignition lockouts caused by a blocked or frozen condensate route.
• Do not overlook intermittent fan behaviour: If the boiler occasionally fails to start, makes unusual noises during startup or repeatedly shuts down before ignition, arrange for the issue to be checked rather than waiting for a fan-related code such as E05, 05E or 17.
• Keep an eye on heating and hot water temperature consistency: Sudden fluctuations in radiator or hot water temperatures can sometimes be an early sign of a sensor or circulation issue. Reporting these changes during an annual boiler service can help identify faults before a sensor code appears.
• Have electrical connections and internal components checked during servicing: Sensor, fan and pressure-related codes can sometimes be linked to wiring or poor electrical connections. An annual inspection provides an opportunity for developing faults to be identified by a qualified engineer.
• Use the boiler normally after a successful reset, but monitor it closely: If a fault clears after a reset, pay attention to whether heating, hot water and pressure return to normal. If the same Ravenheat code reappears, arrange for professional diagnosis instead of repeatedly resetting the boiler.

Get Protection When Ravenheat Boiler Faults Strike

Ravenheat boiler error codes can sometimes be resolved with simple checks, such as restoring low water pressure or resetting the boiler. However, faults involving ignition, circulation, fans and sensors can require professional repairs and may lead to unexpected costs.

A PlusHeat boiler cover plan can help you prepare for unexpected boiler breakdowns and faults. Rather than worrying about the potential cost of call-outs, parts and labour when a Ravenheat error code points to a more serious issue, you can have cover in place to provide added peace of mind.

PlusHeat offers a range of boiler cover plans, allowing homeowners and landlords to choose the level of protection that best suits their needs.

Frequently Asked Questions

What should I do if my Ravenheat boiler shows a code that is not listed in the manual?

Note the exact code and any lights or symbols, then check the official Ravenheat support resources or contact a Gas Safe engineer. Different ranges (CSI, CS, WH, HE) can use slightly different displays, so matching the full code to your exact model is important.

Can a power cut cause Ravenheat boiler error codes?

Yes. After a power interruption some boilers display a general lockout, software error or ERR code. Once power is stable, a single reset often clears it. If the code returns, the control board or wiring may need checking.

How often should I check my Ravenheat boiler pressure to avoid error codes?

A quick look at the pressure gauge once a month is sensible, especially before winter. Aim for 1.0–1.5 bar when the system is cold. Catching a slow pressure drop early helps prevent E08 or 08E from appearing.

Do Ravenheat error codes differ between combi and system boilers?

Many core codes (pressure, ignition, sensors, fan) are shared, but system models may show additional codes related to the cylinder or different hydraulic arrangements. Always refer to the specific handbook for your model.

Is it safe to keep using the boiler if an error code clears after a reset?

Only if the code does not return and the boiler runs normally with stable pressure and even heating. Any recurring code, unusual noises, or smell of gas means stop using it and call a qualified engineer.