Remeha E.00.01 Fault Code: Causes, Fixes & Repair Costs
What does the Remeha E.00.01 fault code mean?
The E.00.01 fault code (also displayed as E[01 on some Remeha models) indicates that the boiler's Power Supply Unit (PSU) has detected that its stored safety parameters are incorrect, corrupt, or missing. The PSU sits at the heart of Remeha's control system and holds the critical operating limits that govern safe boiler operation. When it cannot verify those values, the boiler locks out completely and will not fire until the issue is resolved. This code appears across the Remeha Calenta, Quinta Pro, and Calora Tower ranges; older Avanta and Gas 210 models display a broadly equivalent fault within the E0 code family. The lockout is a deliberate safety measure — the boiler is refusing to operate rather than risk running outside its safe boundaries.
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
- Corrupt or lost PSU safety parameters Common
The most frequent root cause. A power surge, voltage spike, or brief power interruption during operation can corrupt the safety data held in the PSU's memory. The board then fails its own self-check on start-up and triggers the lockout. A Gas Safe engineer with Remeha diagnostic equipment can often reprogram the correct factory values without replacing the board.
- Faulty or degrading PSU/PCB board Sometimes
If the board itself is failing — through age, heat stress, or component failure — it may be unable to retain or verify its parameters even after reprogramming. In these cases the PSU needs to be replaced. This is more likely on boilers that are seven or more years old or that have had repeated lockouts.
- Loose or damaged wiring between PSU and control unit Sometimes
A poor electrical connection — a loose plug, corroded terminal, or chafed wire — between the PSU and the main control board can prevent the system from correctly reading the stored parameters. The fault may appear intermittently and clear temporarily before returning.
- Abrupt power interruption during operation Rare
A sudden mains power cut while the boiler is running can occasionally corrupt the memory on the PSU board, in the same way that pulling the plug from a computer mid-operation can corrupt files. A single reset after power is restored sometimes clears this.
How to fix it
- Note the fault code displayed on the boiler DIY safe
Before doing anything else, make a note of the exact code shown — E.00.01 or E[01. This helps any engineer you call to prepare and speeds up the diagnosis. Take a photo of the display if it helps.
- Attempt a boiler reset DIY safe
Press and hold the reset button for approximately two seconds. If the display shows SERVICE rather than RESET, switch the boiler off at the mains, wait ten seconds, then switch it back on. Do not reset the boiler more than two or three times in total — repeated resets without a fix can mask the underlying problem and are not safe practice.
- Check your mains electricity and gas supply DIY safe
Make sure the boiler's mains switch is on and that other appliances in the property are working normally. Confirm your gas supply is active by checking another gas appliance such as a hob. If there is no gas supply, contact your gas supplier rather than attempting further boiler work.
- Do not attempt to inspect or reseat internal wiring yourself Gas Safe engineer
Although loose wiring is a known cause of this fault, accessing the internal components of the boiler to check connections involves working inside a live gas appliance. This must only be done by a Gas Safe registered engineer. Do not remove the boiler casing or touch any internal wiring.
- Call a Gas Safe registered engineer to diagnose the PSU Gas Safe engineer
If the fault returns after a reset, you need a qualified engineer. They will use Remeha-compatible diagnostic tools to read the PSU's stored parameters, determine whether reprogramming is possible, and replace the PSU or PCB if the board is found to be unrecoverable. Ask for confirmation of their Gas Safe registration number before they begin work.
Parts you may need
- Remeha PSU / PCB control board · from £280
- Wiring harness / connector loom · from £45
- Control unit / display board (where separate) · from £120
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 £150–£400, depending on the underlying cause.
Frequently asked questions
Can I fix the Remeha E.00.01 fault myself?
The only safe DIY steps are trying a reset (up to two or three times) and checking that your mains power and gas supply are working. Everything else — checking internal wiring, reprogramming the PSU, or replacing any boards — must be carried out by a Gas Safe registered engineer. Working inside a boiler without the correct qualifications is illegal for gas-related work and dangerous.
Will a reset permanently fix the E.00.01 fault?
Occasionally, yes — if the fault was caused by a one-off power interruption, a single reset after power is restored can clear it. However, if the fault reappears after one or two resets, the PSU parameters need reprogramming or the board needs replacing. Repeatedly resetting without investigation is not recommended.
How much does it cost to repair a Remeha E.00.01 fault in the UK?
Most people pay between £150 and £400. If an engineer can reprogram the safety parameters during a single visit, the bill is typically at the lower end of that range. If the PSU or PCB board needs replacing, expect to pay £250–£400 including parts and labour. In rare cases where other control components are also damaged, costs can exceed £500 — worth bearing in mind if your boiler is already ten or more years old, when a replacement boiler may be more economical.
Is the E.00.01 code the same as E[01 on my Remeha display?
Yes, they refer to the same underlying fault. Newer Remeha models such as the Quinta Pro and Calora Tower tend to display the full E.00.01 format, while some Calenta models and older units show E[01. Both mean the PSU has detected incorrect safety parameters and the boiler has locked out. The diagnosis and repair process is identical regardless of which format appears on your display.