This is probably one of the most common issues that we hear about hoods, the motor isn’t working or it’s not spinning up to speed and people assume that they need a new motor. Which, by the way, isn’t always the case as we’ll explain.

People have this “go-to” often of whatever ails their appliance must be the worst, most expensive possible thing it could be when, when we’re repairing things, the opposite is true, we’re looking for the cheapest and easiest fix, not the worst we can think on out the traps.

With hoods the great things is that, aside from often being a pain to work on as you need three hands and to be able to work upside down, they’re actually pretty simple things.

After all, it’s a switch, often a small PCB or electronic board or two, a motor perhaps a capacitor and that’s it in terms of functional parts. All the rest is usually what we regard as window dressing, lights and cosmetic stuff.

So when a fault in the motor is reported, there are limited options on what the problem might be.

Cooker Hood Motor

Normally these will be induction motors, nobody here can recall ever seeing anything else in a domestic cooker hood so, there are no carbon brushes or anything like that. Induction motors tend to be extremely reliable and more often than not the bearings will fail long before the coils or stator will fail. 

In short, while they do go, it’s not the “go-to” component that you’d first assume to be knackered if the reported fault is that it’s not spinning up etc.

What controls or powers that motor, that’s a different story.

Motor Capacitor

Normally, but not in all, there will be a motor start/run capacitor that basically gives the motor the “grunt” to start and run, and these do fail. Many charges and discharges over the years, and eventually, they all do.

Generally, symptoms of a dodgy capacitor will be the motor not starting at all, a humming noise but no motor action or it runs but doesn’t get up to full power, turning slowly. Occasionally you can get reports of noise but it will usually prove to be doing one of the other things mentioned as well.

But capacitors are cheap and usually heaps easier to change the motor so, if you’re not sure and any of the above descriptions apply, we’d start there.

You do, of course, need to get the right one, and that’s where you need us on spares@ukwhitegoods.co.uk to make that happen.

Cooker Hood Electronic Modules

Some cooker hood motors are controlled by electronics of varying degrees of complexity, that really depends on how swanky the hood is to be blunt about it. But most are reasonably straightforward though rarely cheap items to replace.

Diagnosing these is more tricky, no doubt about that as if they power the motor there will invariably be a board that’s a “user input” one that forms the control panel that tells the main control module what to do and, in rare cases, a third one that powers the motor.

But if you don’t have the ability to test stuff then for most with two boards, when the motor is playing up and not running the highest probability is that the control board will be duff, not the motor. Again, we can’t say this is for certain and certainly not in every instance, but the likelihood of it is much higher.

Switches & Input Boards

Where there’s a main module in a cooker hood these are (usually) dumb devices that tells the main board what to do, that in turn tells the motor and lights what to do based on your input. Hence, user input board.

Very few will have any sort of direct control over the motor these days.

Back in the day, sure you had a switch unit that directly controlled the motor but those sorts of designs have been on the way out for many years and it tends to be legacy products that would see that sort of a setup. Not all, of course; there are some “budget” brands that you can still find such a thing used in, but it’s not so common now.

Assumptions

There’s a saying in the repair trade, “Assume nothing, check everything”.

With very good reason as often what people, including pro-repairers on occasion, will assume to be the problem often turns out not to be. Guessing is not advised, checking things is.

And that is very true of thinking that the motor in your cooker hood is kaput when there’s a pretty good chance that’s not the problem and replacing it without checking things or, at least considering them, could prove to be an expensive mistake.