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Ideal boiler codes
Checked against its sources: Updated
Ideal boiler fault codes here come from two older user guides: letter codes on the Logic Combi and plain-English messages on the Logic+.12 Neither is the current issue and neither is hosted by Ideal, so check against your own guide.
- Covers
- Ideal Logic Combi and Logic+ Combi 24, 30, 35; Logic Max on web-page evidence only
- You
- Reset by the knob where the guide says, check the gauge and refill by the guide's loop method, check other gas appliances and prepayment credit.
- A professional
- Anything that fails after those steps. Ideal if under warranty, or a Gas Safe registered engineer outside it.
1 Fault displays
The table pairs each Logic code with the Logic+ message that has the same description; that pairing is by description only. "Contact" means Ideal if under warranty, otherwise a Gas Safe registered engineer.
| Code or display | What the Ideal guide says | Which manual, page | What the Ideal guide lets you do |
|---|---|---|---|
| F6 / Outside Sensor Fault | Outside sensor failure | Logic p71; Logic+ p172 | Reset, then contact |
| F7 / Low Mains Voltage | Low mains voltage | Logic p7; Logic+ p17 | Contact an electrician or electricity provider |
| F9 / PCB Fault | Unconfigured PCB | Logic p7; Logic+ p17 | Contact; no reset offered |
| L5 / Too Many Resets | 5 boiler resets in 15 minutes | Logic p7; Logic+ p17 | Turn power off and on at the fused spur, then contact |
| L6 / Lockout 6 | False flame lockout | Logic p7; Logic+ p17 | Reset, then contact |
| C0 / Boiler Type Card Fault | BCC activation fault | Logic p7; Logic+ p18 | Reset, then contact |
| C2 / PCB Replacement | BCC fault | Logic p7; Logic+ p18 | Reset, then contact |
| F1 / Low Water Pressure | Low water pressure; boiler won't run below 0.3 bar (Logic p4, Logic+ p11) | Logic p7; Logic+ p18 | Check the gauge shows 1 to 1.5 bar; refill by the guide's loop method |
| L1 / Overheat Lockout | Flow temperature overheat or no water flow | Logic p7; Logic+ p18 | Check 1 to 1.5 bar; Logic+ adds bleed radiators, check radiator valves are open, reset |
| F2 / Flame Loss | Flame loss | Logic p7; Logic+ p19 | Check other gas appliances work; check prepayment credit. Look at the meter valve only: if it is off, don't turn it on or reset, ring your gas supplier or an engineer; otherwise contact |
| L2 / Ignition Lockout | Listed with Flame Loss; failed ignition, which a blocked condensate pipe can cause, with gurgling first | Logic pp4, 7; Logic+ pp7, 12, 19 | As Flame Loss, and reset; thaw only as below |
| F3 / Fan Fault | Fan fault | Logic p7; Logic+ p19 | Reset, then contact |
| F4 / Flow Thermistor Fault | Flow thermistor | Logic p7; Logic+ p19 | Reset, then contact |
| F5 / Return Thermistor Fault | Return thermistor | Logic p7; Logic+ p19 | Reset, then contact |
| F4 / L4 (Logic) | Flow thermistor | Listed on Ideal's website, not in the user manual read; L4 isn't in the 2013 table3 | The page suggests restarting, then contacting Ideal |
| Too Many Restarts (Logic Max) | Too many restart attempts in a set period | Listed on Ideal's website; no Logic Max manual read. Logic+ prints "Too Many Resets"4 | The page says power off and on at the fused spur, then contact |
| Outside Sensor Fault, Fan Fault, PCB Fault (Logic Max) | Sensor; fan; PCB not configured | Listed on Ideal's website; no Logic Max manual read4 | The page suggests restarting for the first two, then contact |
2 Normal-running displays on the Logic Combi
| Display | Meaning |
|---|---|
| 0 | Standby, no demand |
| C, burner light off | Heating call, boiler already at set temperature |
| d, burner light off | Hot water call, boiler already at set temperature |
| C, burner light on | Heating |
| d, burner light on | Hot water |
| P, burner light on | Pre-heat |
| F, burner light on | Frost mode |
3 How the reset works
Turn the mode knob to the reset position and immediately turn it back; there is no hold.12 The one exception is clearing a service reminder on the Logic+: hold at reset for 3 seconds.2 Try once, because five resets in 15 minutes becomes a fault of its own. Both guides also say a boiler with a known or suspected fault must not be used until an engineer has corrected it.12
4 Pressure and frozen pipes
Both guides give a filling-loop method and a 1 to 1.5 bar target; see repressurising. Both allow thawing a condensate pipe only if you feel competent, and never above ground level; see frozen condensate pipe.12 For a suspected gas leak, go to the gas entry.
5 What wasn't covered
Ideal's current Logic+ guide (215419-7) and Logic Max guide (219008-2) couldn't be retrieved, so newer boilers may show different wording. The user manuals read don't list other codes, and your own guide takes priority over this entry.
Sources
- Ideal Logic Combi 24, 30, 35 User's Guide, no document number in the copy read, file dated 17 July 2013, hosted by InspectApedia, not by Ideal read 3 November 2026.
- Ideal Logic+ Combi 24, 30, 35 User Guide, UIN 204979 A07, May 2014, hosted by Selco, a builders' merchant, not by Ideal read 3 November 2026.
- Logic Combi troubleshooting guide, Ideal web page, not a manual read 3 November 2026.
- Logic Max Combi troubleshooting manual, Ideal web page read 3 November 2026.