Appliance
La Cornue cooktops and rangetops
A La Cornue cooktop is a set of modules chosen at order time and dropped into a stainless frame: brass gas burners at 17,000 and 7,500 BTU, a 22,000 BTU power burner, the cast-iron plaque coup de feu heated by a single burner underneath, a lava-rock grill, ceramic-glass induction zones, an electric teppanyaki plate. This is the top of a range, and each module is a different repair. Sold on its own without ovens beneath it, the same top is a rangetop, and it has its own page.
- 13 symptoms we are called out to
- From $95 diagnostic, credited to the repair
- 59 cities and neighborhoods covered
- OEM parts available on order
The short version
What this equipment is, for a repair
Configurations
Brass gas burners · plaque coup de feu · lava-rock grill · induction · teppanyaki
Access
Planned before the visit, not discovered on arrival
Parts
OEM, available on order
Diagnostic
From $95, credited to the repair
What goes wrong with it
Symptoms we are called out to on La Cornue cooktops and rangetops
Each one covers the likely causes in the order they are worth checking, and what to do in five minutes before booking anything.
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No flame, and no obvious reason Burner will not light
One burner dead while the others work is a different problem from a whole top that will not light, and the two are worth separating before anybody calls anybody. On brass burners in a humid kitchen the single dead burner is nearly always the electrode or the ports; a whole top points at the ignition module or the gas supply.
- One burner out is that burner — not the module
- All of them out is ignition or supply, and it is quick to tell
- Never hold the knob in while it clicks
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The spark is there and the flame is not Burner clicks but will not ignite
Continuous clicking with no flame — or clicking that carries on after a burner has lit — is one of the two or three most common calls on any gas range, and on this one it has a short list of causes. It is also the symptom people live with longest, and it should not be: every click is unlit gas.
- Clicking after ignition is usually a wet or dirty electrode
- Clicking on every burner at once points at the module
- It is a small part and a same-visit job in most cases
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The flame is the wrong color Yellow or orange flame
A gas flame on this range should be blue with a defined inner cone. Yellow or orange tips, soot on the bottom of a pan and a smell of unburnt gas mean the air-to-gas mixture is wrong, and on a range that has moved house or changed fuel that has a specific and common cause.
- Blue is correct — yellow is an air, fuel or orifice problem
- A bad propane conversion is the leading cause on a relocated range
- Soot on a pan bottom is the symptom people notice first
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It lights and then goes out Burner will not stay lit
A burner that lights while the knob is held and dies when it is released is a flame supervision failure, and it is the same problem whether it happens on a surface burner or in the oven. The safety system is doing what it exists to do; the reason it no longer trusts the flame is what needs finding.
- The safety chain is working — it just no longer sees the flame
- Thermocouple, then valve, in that order
- An oven that does this is a same-day call
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It lights, but there is no heat in it Weak or uneven flame
A burner that lights cleanly and produces half the heat it used to, or a flame that is tall on one side of the crown and absent on the other. On a range whose front burners are rated at 17,000 BTU and whose power burner is rated at 22,000, a weak flame is not a small loss — it changes what the range can do.
- Uneven around the crown is ports or a misseated cap
- Weak on every burner is supply pressure or a regulator
- The plaque burner is the one nobody notices has weakened
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Stop and read this first Gas smell in the kitchen
A smell of gas is the one symptom on this site with instructions rather than a diagnosis. Turn the range off at its shut-off valve, open windows, do not operate switches or the hood, and get everyone out if the smell is strong. Then call the gas utility or 911 first and us second.
- Utility or 911 first, appliance repair second
- Do not operate switches, the hood or a phone in the room
- A faint smell only while lighting is a different matter from a persistent one
What we do on it
Repairs we carry out on La Cornue cooktops and rangetops
Starting figures for this equipment in South Florida. The exact cost is confirmed after an on-site diagnostic — and this is not the whole list of what can go wrong, so call if your problem is not here.
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from $95 Diagnostic visit
One visit, one technician, one answer in writing. On a make with three error codes in its entire documentation, the diagnostic is not a formality before the repair — it is the repair's only source of information, and it is done with instruments rather than by elimination.
- Measured, not guessed — this make reports almost nothing on its own
- The configuration code read off the range, because it decides the parts
- Written findings and a from-price before anything is opened
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from $195 Appliance maintenance
An annual visit that exists because most of what goes wrong on this make goes wrong slowly. Burners drift rich, thermostats drift hot, baffles saturate, brass tarnishes, and the owner adapts to every one of them without noticing. This is the visit that measures instead of adapting.
- Burner combustion and oven calibration checked against specification
- Baffle filters, duct flow and blower condition on the hood
- Enamel, trim and seals inspected while they are still repairable
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from $295 Appliance installation
A Château is delivered in a crate that can weigh 1,320 lb and is leveled to a specification, not to a spirit level held by eye. Installation covers gas, electrical, leveling, hood duct and the first-use check — and it covers the paperwork, because altitude, fuel type and voltage are specified at order time and have to match what is actually in the house.
- Gas and electrical to the maker's own requirements document
- Leveled to specification — a dish of water sits at one depth all over
- First-use check, and the hood duct measured rather than assumed
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from $155 Surface burner and igniter service
Clicking with no flame, a burner that lights and will not stay lit, a lazy yellow flame. On brass burners in a coastal kitchen these are three symptoms of a short list of causes, and none of them is the ignition module when only one burner is affected.
- One burner out is the electrode or the ports — not the module
- Yellow flame is air mix, fuel or an orifice, and it is measurable
- Ports cleared properly rather than poked at
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from $265 Gas valve and thermocouple repair
The safety chain: a valve that will not hold open, a thermocouple that no longer tells it to, a knob that has gone stiff or will not shut off cleanly. This is the part of a gas range where nothing gets improvised and nothing gets left half-diagnosed.
- Safety valve and flame supervision tested as a system
- Stiff or leaking knob valves rebuilt or replaced, never lubricated over
- Leak-checked at every joint that was opened
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from $245 French top service
The plaque coup de feu is a single cast-iron plate heated by one 7,500 BTU burner directly under its center, and it is the most-used and least-understood part of the range. Cracks, warping, rust, dead cold spots and a burner running wrong underneath are all different problems that present the same way.
- Crazing in the seasoning and a crack through the iron are told apart
- The burner beneath it checked first — most cold spots start there
- Re-seasoned properly, so the plate is handed back working
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from $225 Lava rock grill service
A linear 14,500 BTU burner under a bed of natural lava rocks, and a module that lives its whole life under fat. Weak or uneven flame, flare-ups, a burner that will not light along its length, and rocks that have turned into a sealed crust are the calls.
- Rock bed replaced rather than raked over
- The linear burner cleared along its whole length
- Drip tray and grate condition treated as part of the job
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from $285 Teppanyaki element repair
The electric griddle module — a solid plate held between 140 and 482 degrees by an element and a control. It fails as electric things fail: no heat, one temperature only, or a plate that will not hold the setting it is given.
- Element, sensor and control measured separately
- The plate checked for flatness — a bowed griddle cooks unevenly and is not a control problem
- Temperature verified across the surface, not at one point
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from $325 Propane conversion service
La Cornue publishes a conversion procedure and a specific parts set for the CornuFé 90 and 110, and specifies fuel at order time on a Château. A conversion done with approximate parts gives yellow flames, soot and burners that will not hold a simmer — and it is one of the most common things we undo on a range that has changed house or fuel.
- The maker's own orifice set, not a universal kit
- Every burner and both ovens set and verified, not just the fronts
- Written record of what the range is now set for
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from $265 Enamel panel and trim service
Vitreous enamel is glass fused to steel and about fifty colors of it were available at order time. A chip is not cosmetic in this climate — the steel under it rusts outwards — and a tarnished brass handrail attacked with the wrong product loses its lacquer along with the tarnish.
- Chips stabilized or the part ordered in the range's own color reference
- Brass, copper, nickel and chrome trim treated by what they actually are
- Clear-coated finishes identified before anything is polished
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from $325 Induction hob repair
The three codes La Cornue documents anywhere all live here: E2, the electronics are too hot; U400, the cooker is incorrectly connected; Er with a number, an internal problem the user cannot clear. Everything else on that display is an indicator, and telling the two apart saves a visit.
- E2 is investigated as ventilation first, as the maker's own guide says
- Indicators — H, the pan-missing symbol, L, A, P — are not problems
- Zone-by-zone testing with pans that meet the minimum diameters
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from $595 Induction glass replacement
The one problem on this make with a safety instruction attached. La Cornue's guide is unambiguous: a cracked hob is disconnected from the power supply immediately and not used until it has been repaired, because the glass is what separates the coils and the electronics from whatever is spilled on it.
- Made safe first, diagnosed second
- Glass ordered to the range's own configuration, not a generic panel
- Coils and electronics inspected for what has already got through the crack
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from $295 Cooktop control and wiring repair
U400 latched on the display, a hob with no display at all, a fuse or residual-current device that trips repeatedly. All three are supply-and-connection problems in the maker's own words, and all three turn up after something in the house changed.
- The appliance connection checked against the maker's specification
- Over-voltage and lost supply distinguished from a dead control
- Findings written down when the problem is upstream of the range
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from $195 Burner knob and valve rebuild
Brass knobs on mechanical valves, used several times a day for decades in a humid kitchen. Stiffness is the early warning; a knob that will not return cleanly to off is the reason this is not a job to postpone.
- A stiff valve is failing, not dry — it is rebuilt or replaced
- Knobs, bezels and stems treated as wear parts
- Every valve on the range checked, not only the one complained about
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from $345 Appliance control board repair
Only part of this make has electronics at all, and where it does — induction generators, multifunction oven controls, the Tourelle, motorized hood controls — a board is the last suspect rather than the first. An Er code and a measured failure send us here; an unexplained symptom does not.
- Supply, sensors and loads eliminated before a board is blamed
- Er numbers documented and quoted, since only the maker's own board clears them
- Lead time stated up front on a hand-built appliance
In more detail
About La Cornue cooktops and rangetops
The top is a set of choices, and every choice is a different repair
La Cornue prices its cooktop elements individually, which tells you how the appliance is meant to be understood. Everything below belongs to the top of a range; the same modules sold as a unit that drops into a counter with no ovens under it are a rangetop, T40 to T48, and that is a separate page on this site. On the Château series: two brass gas burners in an enamelled drip tray, 17,000 BTU at the front and 7,500 at the back on natural gas. A 22,000 BTU power burner for a stock pot. The plaque coup de feu, large or petite, where one 7,500 BTU burner heats a solid cast-iron plate that becomes the whole cooking surface, hottest above the burner and cooler as you work outwards. A lava-rock grill at 14,500 BTU. Ceramic-glass induction, 2,100 watts a zone and 3,700 on boost. An electric teppanyaki plate running from 140 to 482 °F. On a single rangetop you might have four of those, and the diagnosis for one tells you nothing about the next. The factory-built CornuFé is specified differently and it is worth knowing which you have: a 17,500 BTU central burner, three at 12,000 and a 6,000 BTU simmer burner on the dual-fuel models, and five separately rated induction zones from 1.4 kW to 2.3 kW on the induction ones.
Induction is the one place this make talks back
The gas half of the line has no diagnostic system at all, so the induction and teppanyaki electronics are the only part of a La Cornue cooktop that reports anything. Three codes, all documented by the maker: E2, the electronic unit is too hot, check ventilation, or a pan has boiled dry; U400, the cooker has been incorrectly connected, control off after a second and the code latched on; Er with a number, an internal problem the user cannot clear. Everything else the display shows is an indicator rather than a problem — H for residual heat above 140 °F, the pan-missing symbol when a zone has nothing on it or the base is too small, L for child lock, A for automatic heat-up, P for boost. Knowing which is which saves a call: an H is the cooktop telling you it is still hot, not that it is broken.
Cracked glass, and why we disconnect it before we discuss it
A crack in a ceramic-glass induction hob is the one problem on this appliance with a safety instruction attached, and La Cornue's guide is unambiguous: disconnect the cooker from the power supply immediately and do not use it until it has been repaired. The reason is that the glass is what separates the coils and the electronics from whatever gets spilled on the surface. We will come and look at a cracked hob, and the first thing we do is make it safe rather than test it. Minimum pan diameters are worth knowing too, because they are the honest answer to a zone that seems weak: 4¾ inches front left, 5½ at the rear, 8¼ in the center. A pan smaller than the zone will not couple properly, and the cooktop is behaving exactly as designed.
This article is based on:
- Official manufacturer documentation
- Internal repair procedures
- Technician repair history
- Company quality standards
Before you book
Questions about La Cornue cooktops and rangetops
The induction zone shows E2 and shuts off. What is that?
That is one of exactly three codes La Cornue prints anywhere in its US documentation, and it means the electronics under the hob are too hot. The manual's own first suggestion is ventilation — how the cooktop is installed and whether air can get to the electronics — and its second is a pan boiled dry, which heats the glass and everything under it. So before we condemn a board we look at the installation: what is packed into the cabinet underneath, whether a fitted drawer or a filled cavity has closed off the air path, whether it happens only during long cooking or from cold. If the ventilation is right and it still cuts out, the problem is in the unit and it is a part. What we will not do is reset it, hand it back and let it cook itself.
U400 came up and the top will not run at all.
U400 means the cooker has been incorrectly connected, in La Cornue's own words. The control shuts down after about a second and the code stays on the display permanently until the wiring is right. It is an electrical-supply problem rather than an appliance failure, and it turns up most often after something changed: a new installation, a panel or breaker replaced, a range moved, work done on the kitchen circuit. That makes it one of the few problems on this make where the answer might be that nothing inside your range is broken. We check the supply and the connection at the appliance against the specification, and if the problem is upstream we say so in writing rather than sell you a board.
My French top has a crack across it. Is it finished?
Not necessarily, but it needs looking at rather than living with. The plaque is a single cast-iron plate heated by one 7,500 BTU burner directly beneath its center, and it is meant to run through a large temperature range and hold heat — so it is under stress every time it is used. Hairline crazing in the seasoning is cosmetic. A crack through the iron changes how heat crosses the plate, and a plate that has been thermally shocked (a wet cloth, a pan of cold liquid on a hot center) can go further. We will tell you which one you have. The other thing we look at is what is under it: a burner running rich, or a blocked drip area, puts more heat into one spot than the plate was designed to spread.
Only one gas burner will not light, and it clicks.
Clicking with no ignition on one burner is nearly always the electrode or the burner ports rather than the ignition module, because a failed module takes all the burners with it. In this climate the usual causes are moisture and cooking residue: a wet electrode after a cleaning, a cracked ceramic that is arcing to the wrong place, or ports partly blocked so the flame cannot travel to the spark. It is a small job and a same-visit one in most cases. Please do not keep holding the knob in while it clicks — that is unlit gas going into your kitchen, and the burner is not worth it.
Where we do it
Across Miami-Dade, Broward, and Palm Beach
Same terms everywhere we go: an on-site diagnostic first, the price agreed in writing, and the exact figure confirmed once we have seen the unit.
Neighborhoods people ask for by name