Ideal Blank displaywhat to check
Nothing on the screen at all. Ideal's user guides send you to the boiler's switch and the consumer unit first; the installer charts then work from the terminal block to the board.
Take care
What this means
A dark display is the one Ideal fault with no code, and every Ideal manual has a chart for it: No Display on the Logic ESP1, Logic Combi2 and Logic Max, Blank Display on the Vogue, and on the Isar the user guide's test of whether a 0 shows on the controls with the switch on — "if 0 not displayed then not a boiler fault, contact your installer".
The householder's share is the supply. The Vogue Max guide says to ensure the mains supply to the boiler is switched on and that no trips have operated in the consumer unit; the Logic Combi2 guide starts every troubleshooting path with "check the mains power is switched on" and asks whether the boiler has a display showing at all.
Behind that, the engineer's chart is the same on every range: is 230 volts reaching the boiler at L and N; is the wiring from the terminal block to the PCB connected and continuous; then, on a Vogue, is the cable from the main PCB to the user interface PCB connected and undamaged, is the fuse on the main PCB intact, and does a new user interface PCB bring the screen back — and only after all of that, replace the main PCB. Most blank displays are the fused spur, a tripped breaker, or a shared circuit taken out by something else in the house, and none of those is a boiler repair.
What causes it
| Cause | What is actually happening | How likely |
|---|---|---|
| No supply to the boiler | The fused spur beside the boiler switched off, its fuse blown, or a breaker or RCD tripped in the consumer unit. Ideal put this first in the user guide and the installer chart alike. | Common |
| Wiring from the terminal block to the board | The second box in every Ideal chart: connected securely, and with continuity. A connector disturbed at a service is the usual reason a boiler goes dark a week later. | Occasional |
| Display board or its cable (Vogue) | The Vogue's screen has a board of its own and a cable to the main PCB, and Ideal check both, plus the fuse on the main PCB, before condemning anything. | Occasional |
| Main PCB failed | The last box on every chart. Supply present, wiring good, screen board good, and still nothing: the board that runs the boiler has gone. | Occasional |
What to try yourself
Find the switched fused spur next to the boiler, or the boiler's own on/off switch on older ranges, and check it is on. On an Isar or Icos, a 0 on the display with the switch on means the boiler has power.
Check the consumer unit for a tripped breaker or RCD and reset it once. Ideal's Vogue guide names this step. A boiler often shares a circuit with sockets, so another appliance failing can take it out.
If the spur has a fuse, a 3 A replacement of the same type is a householder's job if you are comfortable doing it; if it blows again, stop. Anything further is inside the boiler or the fixed wiring.
Do not open the boiler casing. Ideal's remaining checks are at 230 volts inside a gas appliance.Still dark with the supply proved? Contact Ideal if the boiler is under warranty, otherwise a Gas Safe engineer — Ideal's Combi2 guide gives exactly that routing.
Get a Gas Safe registered engineer to look at your Ideal boiler
We do not pass enquiries to a repair firm, so there is no form here. Find a Gas Safe registered engineer through the Gas Safe Register, and ask to see their registration card when they arrive — it is the register, not the van, that tells you they are qualified.
What it costs to fix
Typical repair cost
£0–£380
Time on site
10 minutes
Nothing if a switch or breaker was off. An electrician to trace a tripping circuit £80–£150. Inside the boiler: a Vogue user interface PCB £150–£280, a main PCB £250–£380 fitted.
Typical UK prices including parts and labour, updated September 2026. Your quote may differ.
Parts you may need
We may earn a commission if you buy a part through one of these links. It does not change what you pay, and it does not affect which parts we list.
Ideal Logic primary PCB
£150–£320Authorised Ideal parts distributor
Price checked 28 September 2026
Own this appliance and had this code? . Nothing is published until a person has read it.
Related Ideal fault codes
- F9Get it checkedThe control board has not been told what boiler it is in, or has failed. L9 is the same fault locked out. The 2011 Logic Combi row also covers a gas valve short circuit.Related: electronics and power
- dUUsually simple to fixNot a fault. The diverter valve has been parked in its mid-position for servicing and the boiler is waiting to be told the service is over. Ideal publish the way out.Related: electronics and power
- F7Get it checkedThe mains voltage reaching the boiler has dropped below what the board will run on. Ideal's advice is an electrician or your electricity supplier, not a heating engineer.Related: electronics and power
- C0Get it checkedThe board cannot activate the Boiler Chip Card that tells it what model it is fitted to. Ideal's engineer check is whether the small plastic card is in its slot at all.Related: electronics and power
- L9Get it checkedOn a Logic, L9 is the locked-out form of the unconfigured-board fault F9. On an Isar HE it is something else entirely: a heat exchanger overheat read by the dry-fire thermistor.Related: electronics and power
- SEUsually simple to fixA service reminder, not a fault. The installer set a timer at the last visit and it has run down. Ideal's advice is to contact the installer, who resets it when the boiler is serviced.Related: electronics and power
Own an Ideal boiler? Save it and its codes come first next time.
Related guides
Common questions
Is a blank display dangerous?
No. A boiler with no power has its gas valve shut, which is the safest state it has. The risk is practical — no heating or hot water, and no frost protection while the power is off — rather than a gas one.
The display is blank but the boiler is warm. How?
On a Vogue that points at the screen's own board or its cable, because the main PCB is evidently running. Ideal's Blank Display chart checks that cable and the user interface PCB before the main board for this reason.
Could this be the L E or PCB fault codes?
No — those need a working display to show. A board fault that produces a code is on the F9, L E or PCB Fault pages; a board so dead it shows nothing is the end of this chart.
Technical review
Not reviewed by an engineer
No engineer has read this page. Severity follows what the manufacturer publishes, and we would rather tell you that than let a byline imply a sign-off.
Sources and how we verified this
We establish the facts from the sources below and then write the explanation ourselves. We do not copy manufacturer wording and we do not host their manuals.
- Manufacturer technical and service documentation
This page has not been reviewed by an engineer, and we would rather tell you that than imply otherwise. The severity rating follows what the manufacturer publishes: where they say isolate the appliance and call someone, so do we.