Salt air
Thermador Ventilation, Hood and Blower Repair
Hoods, inline blowers and roof-mounted units. The motor is often nowhere near the kitchen, and on the coast it is sitting in salt air all year.
Symptoms we hear
Behaviour rather than a code: we do not publish fault codes we cannot verify, and a symptom narrows a diagnosis further than a number.
- The hood lights work but the blower does not start
- Airflow has dropped noticeably while the motor still runs
- The blower hums for a moment and then stops without spinning up
- A grinding or rumbling noise that changes with fan speed
- The hood runs only at one speed regardless of the setting
- Halogen or LED lamps fail repeatedly in the same position
- Outside air blows back into the kitchen when the hood is off
- The hood trips a breaker when the highest speed is selected
What actually fails
- Blower motor bearings and run capacitors, particularly on remote and roof-mounted units
- Roof and exterior blower housings corroding in coastal air, which seizes fasteners and shortens motor life
- Control switches and speed boards inside the hood canopy, exposed to grease-laden air
- Backdraft dampers stuck open or closed, which produces airflow complaints with a healthy motor
- Baffle filters and grease build-up in the duct run, which reduces airflow without any electrical fault
- Lighting circuits and lamp holders, which fail locally rather than across the whole hood
The motor is usually not in the kitchen
Serious kitchen ventilation is rarely a self-contained box over the range. On most of the installations we service, the canopy in the kitchen holds the filters, the lights and the controls, while the actual work is done by an inline blower in the attic or a blower unit mounted on the roof. That split is good engineering, because it moves noise and vibration away from the room. It also means that a hood which will not run may have absolutely nothing wrong with it in the kitchen.
We diagnose these systems in the order the air travels. Controls and switching first, since they are accessible. Then the wiring run to the blower, then the blower itself, then the duct and the damper. Skipping to the motor because the motor is the expensive part is how people end up paying for a motor that was fine.
Salt air and roof-mounted blowers
Along the coast, an exterior blower lives outdoors in chloride-laden air for its entire service life. Ponte Vedra Beach, Jacksonville Beach, Atlantic Beach, Neptune Beach and the older waterfront streets of St. Augustine are all close enough for that to be a genuine engineering factor rather than a talking point.
What we find on those units is predictable: corrosion on the housing and the mounting hardware, fasteners that will not come out without being drilled, bearings that have run dry and rough, and capacitors that have aged in heat and humidity. A motor that hums and does not spin up is very often a failed run capacitor rather than a failed motor, and that is a cheap part with an expensive reputation.
We carry stainless replacement hardware for coastal jobs, because reusing a corroded fastener on a roof unit is a return visit waiting to happen.
Airflow complaints with a healthy motor
A lot of ventilation calls turn out not to be electrical at all. Baffle filters that have not been through a dishwasher in a year cut airflow substantially. Grease accumulates in the first few feet of duct and narrows it. Backdraft dampers stick, either shutting off the exhaust or letting hot outside air push back into the kitchen, which in a Florida August is immediately noticeable.
There is also the make-up air question. High-capacity blowers move a lot of air out of a house that is built to be tight, and when the house cannot replace that air, the blower cannot move it either. The measured airflow drops, doors get hard to open, and in the worst case a gas appliance elsewhere in the house is affected. If we find that pattern, we tell you, because no motor replacement fixes it.
Kitchen exhaust is not the house’s ductwork
Worth separating, because the two get confused on the telephone. The duct we work on runs from the hood or the downdraft to a roof or wall cap, it carries grease-laden exhaust out of the building, and it belongs to the appliance. The ductwork that carries conditioned air around the house belongs to the heating and air-conditioning system, and it is not ours: we do not service, clean, reroute or replace it, and we do not touch furnaces, heat pumps or air handlers. If the complaint is that a room will not cool, the call is for an HVAC contractor. If the complaint is that the hood is loud, weak, dripping or dead, that is this page.
Make-up air is where the two trades genuinely meet, and even there the boundary holds: we can tell you that the house cannot replace the air the blower is removing, and that no motor replacement will fix it, but the remedy is somebody else’s work.
Why ventilation matters to your other appliances
Grease that the hood does not capture ends up somewhere. On a rangetop it works into the igniters and the valve stems. On a wall oven and a speed oven it is drawn through the cooling path and settles on electronics. On an induction cooktop it coats the cooling fan that is protecting the inverters. When we see repeat failures across a kitchen, the hood is one of the first things we look at, and it is very often the cheapest thing to correct.
Terms
Flat $80 diagnostic, credited toward the repair when you approve the work. Written estimate before any part is ordered or fitted. Genuine OEM parts through the BSH channel, 90 days on labour, 365 days on parts. Appointments Monday to Friday 8am to 6pm, Saturday 9am to 4pm.
Local factor
Salt air
Chloride-laden air off the ocean reaches condensers, fasteners and hinges in the coastal ZIPs long before anything wears out mechanically.
Which is why the first questions on a call are where the appliance is installed and how long it has been there, not which model it is.
How the visit works
Diagnostic
$80 flat diagnostic, credited toward the repair when you approve the work.
Estimate
A written estimate comes before any part is ordered or fitted. How pricing works
Warranty
90 days labour, 365 days parts, genuine OEM components. Warranty terms
Parts
Genuine OEM parts, ordered through the same BSH distribution channel that serves Thermador, Bosch and Gaggenau.
Price bands
Parts and labour together, for work completed.
What does ventilation repair cost?
Between $80 and $1,100, depending which component is at fault. Before the appliance is opened a band is the honest answer; a single number is a guess in a quote's clothing.
| What turns out to be at fault | Typical range |
|---|---|
| Diagnostic visit, credited against the repair | $80 |
| Control board or touch panel | $440–$1,100 |
| Convection fan or motor | $260–$710 |
Asked before a ventilation visit
Is the $80 diagnostic charged again if a part has to be ordered?
No. $80 is charged once; the fitting visit is the same job, and the charge is credited against the repair once you approve it. A written estimate comes before any part is ordered or fitted.
The hood lights work but the blower does not start — what is usually behind that?
The short list on this class is blower motor bearings and run capacitors; roof and exterior blower housings corroding in coastal air; control switches and speed boards inside the hood canopy. We reproduce the complaint and measure rather than take it on description: those are separable on the day, and replacing the wrong one is how an owner pays twice.
Is a ventilation repair worth it, or is it time to replace?
Past the diagnosis, control board or touch panel usually lands at $440–$1,100, and convection fan or motor at $260–$710. Replacing instead is $4,200–$14,500 for the equipment alone, before delivery, fitting, or the joinery a built-in is cut into. On this class the repair wins the arithmetic far more often than it loses it.
What moves the figure up or down after the diagnosis?
Which component it turns out to be, before anything else: the table above is a band per part class, not per symptom. After that it is whether the part is current or a superseded revision, whether the appliance has to come out of its opening to reach it, and whether a second fault shows while it is open.
What happens after the repair is finished?
90 days labour, 365 days parts, genuine OEM components. Genuine OEM parts, ordered through the same BSH distribution channel that serves Thermador, Bosch and Gaggenau. Anything you notice afterwards on the work we did is a telephone call, not a fresh diagnostic.
Customer reviews
4.3 out of 5, across 101 customer reviews
After a ventilation visit
One visit each, in the words we were given, unflattering ones included.
Our inline unit in the attic had become unbearable to sit under. He rebalanced the wheel, replaced perished anti vibration mounts and fitted a new flexible connector at the collar. Quiet from the kitchen now.
Ferdinand D.2026-05-25
The extraction works again after a new switch panel. What I object to is being talked at rather than talked to. I asked twice what had actually failed and never got a straight explanation.
Milo L.2025-03-20
The blower on the roof had stopped while the lights carried on as normal. He went up, found the motor seized and its housing badly corroded, fitted a new motor and sealed the mounting properly.
Dashiell B.2026-04-29
Where this comes up
Areas naming this appliance class lead, then the rest — nearest by road within each.
12 mi by road · 24 min
Orange Park
18 mi by road · 26 min
World Golf Village
18 mi by road · 30 min
Oakleaf
22 mi by road · 35 min
Ponte Vedra Beach
28 mi by road · 40 min
St. Augustine
30 mi by road · 45 min
The Beaches
Read first
Articles covering this appliance class, pulled from their own frontmatter.
6 min read
Salt air and stainless
In the coastal ZIPs, chloride air works on condensers, hinges, fasteners and roof-mounted blowers every day of the year. What fails first and what helps.
6 min read
Before you call
Some faults are not faults. A short list of checks worth doing first, and the details that make a diagnostic visit faster and cheaper when one is needed.
Related appliances
Gas rangetops
Star burners, ExtraLow simmer and a griddle or grill module in one drop-in top. Most faults are ignition, gas flow or a control that has stopped cycling correctly.
Professional ranges
One appliance doing two jobs. The rangetop half and the oven half fail in completely different ways, and a range visit has to cover both properly.
Induction cooktops
Full-surface induction is an electronics platform under a sheet of glass. When a zone dies it is almost never an element, and diagnosis has to start at the inverter boards.
Wall ovens
Built into cabinetry, carrying a heavy door and a lot of heat. Wall ovens fail at the door, at the sensor and at whatever the last self-clean cycle pushed too far.
One of nine classes, and nothing outside the kitchen
Meridian Appliance Works opens built-in kitchen appliances, and that is the whole list: Thermador wall ovens, steam ovens and speed ovens, professional ranges, gas rangetops, induction cooktops, refrigerator, freezer and wine columns, dishwashers, and the ventilation hung over the cooking surface.
We do not service heating, air conditioning or ductwork. No furnaces, no heat pumps, no air handlers, no mini-splits, no duct cleaning and no duct replacement — not as a sideline, and not handed to a partner firm. A house that will not warm up or will not cool down is a licensed HVAC contractor's job, and we say so on the telephone instead of booking a visit we could not finish.
Independent, and saying so plainly
Meridian Appliance Works is an independent service company. We name Thermador only to say which appliances we work on: built-in equipment from Thermador and the rest of the BSH Home Appliances line, diagnosed and repaired by our own technicians using genuine OEM parts.
Next step
Book a diagnostic
Tell us the appliance and what it is doing. We will give you a written estimate before anything is ordered.
Mon–Fri 8am–6pm · Sat 9am–4pm
Request a visit- $80 flat diagnostic, credited toward the repair when you approve the work.
- 90 days labour, 365 days parts, genuine OEM components.