Remeha E.02.47 Fault Code: Causes, Fixes & Repair Costs
What does the Remeha E.02.47 fault code mean?
E.02.47 is a hard lock-out code on Remeha boilers, meaning the boiler has shut itself down completely and will not attempt to restart on its own. The code indicates that the boiler's main control unit — the CU-GH PCB — has been unable to locate or establish a connection with one or more of its internal electronic function groups (sub-modules that the control board expects to communicate with during start-up and operation). In short, this is an internal electronics or communication failure rather than a gas, water pressure, or flue problem. Because it is an E-prefix code in Remeha's fault hierarchy (A = warning, H = blocking, E = lock-out), the boiler will remain off until the underlying cause is resolved and the unit is properly reset or repaired.
General guidance only — not a substitute for professional advice, and not certified by a Gas Safe engineer. Always have your specific appliance assessed by a qualified professional. Any gas work must be carried out by a Gas Safe registered engineer. If you smell gas or suspect carbon monoxide, leave the property and call the National Gas Emergency line on 0800 111 999.
Common causes
- CU-GH PCB failure or partial failure Common
The most likely culprit. The CU-GH is the main control board at the heart of the boiler, and E.02.47 specifically flags that the board has failed to detect an expected function group. Remeha's own service documentation points to PCB replacement as the primary resolution pathway. Partial failures — where one sub-module on the board stops responding — can trigger this code even when the rest of the boiler appears undamaged.
- Transient internal communication error Sometimes
On occasion, a temporary disruption to the communication between internal electronic modules — caused by a voltage spike, a brief power interruption, or vibration loosening an internal connector — can produce this lock-out without any permanent hardware damage. A power cycle or engineer-led auto-detect procedure sometimes clears it, though this is less likely on repeated occurrences.
- Corrupted or missing board parameters Sometimes
The CU-GH PCB stores configuration and safety parameters. If these become corrupted — through a firmware issue, a failed update, or gradual memory degradation — the board may fail to initialise its function groups correctly. Adjacent fault codes in the same Remeha service manual (such as E04.00, relating to missing or incorrect safety parameters) point to this as a recognised failure mode in this boiler range.
- Physical damage or moisture ingress to the PCB Rare
Although less common, corrosion or moisture on the control board — perhaps from a slow internal leak or condensation in the boiler casing — can disrupt the communication pathways between the board's sub-modules. This tends to be found on older appliances or those in poorly ventilated installations.
How to fix it
- Check for a simple power interruption first DIY safe
Before assuming an electronics fault, confirm the boiler has a stable mains supply — check the fuse in the spur or consumer unit and ensure no other appliances on the same circuit have tripped. A brief power fluctuation can occasionally cause a transient lock-out that looks identical to a hardware fault.
- Attempt a single boiler reset DIY safe
Press and hold the reset button (or follow the reset procedure in your boiler's user guide) once. If the boiler lights and runs normally, monitor it closely over the next 24 hours. Do not reset more than two or three times in total; repeated lock-outs mean the underlying fault has not cleared and further resets will not help.
- Call a Gas Safe registered engineer to perform an auto-detect Gas Safe engineer
Remeha's official service guidance recommends running an auto-detect procedure as the first diagnostic step — this is a re-scan of all connected function groups accessed through the boiler's engineer service menu. This requires specialist knowledge of the Remeha diagnostic interface and must be carried out by a qualified professional, not a homeowner.
- Engineer to inspect internal wiring and connector integrity Gas Safe engineer
With the boiler isolated from the mains, the engineer should check for loose, corroded, or damaged connectors on the CU-GH PCB and between internal modules. A dislodged connector can mimic a full board failure and is a much cheaper fix if found. Any signs of moisture or corrosion on the board should be documented before deciding on a repair strategy.
- Engineer to replace the CU-GH PCB if fault persists Gas Safe engineer
If the auto-detect procedure and connector checks do not resolve the code, replacement of the CU-GH control board is the standard remedy indicated in Remeha's service documentation. Ensure the engineer sources a genuine Remeha-compatible board and carries out any required parameter programming after fitting. Ask the engineer to test all related components before and after the repair — in some cases a failing board can mask or cause secondary faults elsewhere.
- If the boiler is older or the repair cost is high, discuss replacement DIY safe
Remeha boilers typically have a serviceable life of around 10–15 years. If your appliance is approaching or past that age and the PCB repair bill is substantial, ask your engineer to give an honest assessment of whether further investment in the boiler is worthwhile compared with the cost of a new installation.
Parts you may need
- CU-GH PCB (main control board) · from £280
- Internal wiring loom / connector harness · from £45
- Boiler fuse (mains spur) · from £3
The exact spare depends on your boiler's GC number (on the data badge). Check this against the part before buying.
Typical repair cost
Expect to pay roughly £300–£550, depending on the underlying cause.
Frequently asked questions
Can I reset a Remeha E.02.47 lock-out myself?
You can try a single reset — this is safe for a homeowner to attempt and will occasionally clear a transient communication glitch. However, E.02.47 is a hard lock-out caused by an internal electronics fault, so if the boiler immediately locks out again or fails to start, further resets will not help. At that point you need a Gas Safe registered engineer to investigate properly.
Will the boiler restart on its own once it shows E.02.47?
No. An E-prefix code in Remeha's fault hierarchy is a lock-out, which means the boiler will remain completely off until the fault is cleared. Unlike a blocking (H-prefix) code — which may resolve itself once a condition returns to normal — a lock-out requires a manual reset at minimum, and in the case of E.02.47 almost always requires an engineer to perform an auto-detect procedure or replace the CU-GH PCB before normal operation can resume.
How much does it cost to fix Remeha E.02.47 in the UK?
The vast majority of E.02.47 repairs come down to replacing the CU-GH control board, which typically costs £180–£300 for the part itself. Add a Gas Safe engineer's labour (usually £50–£80 per hour, with the job taking one to two hours) and most people pay somewhere between £300 and £550 all in. If the board needs to be specially ordered, or if a second component is also found to be faulty, costs can edge higher — occasionally up to £700 or more — but this is not the typical outcome. If your boiler is over 10 years old, it is worth asking your engineer whether repair or full replacement makes better financial sense.
Could anything other than the PCB cause E.02.47?
In rare cases, a loose internal connector or a brief mains power disturbance can trigger this code without any permanent hardware damage — an engineer's auto-detect scan will usually identify this quickly. Corrupted board parameters are also a possibility, and some engineers can attempt to reload these before committing to a full PCB replacement. That said, Remeha's own service documentation lists PCB replacement as the primary fix, so if the simpler checks draw a blank, a new control board is almost certainly required.