Restaurant Ventilation Not Working: Guide With Examples & Solutions

The restaurant kitchen’s ventilation is without a question one of the most important appliances in the whole building and when that stops working there’s a chance that the whole business will stop momentarily.

There are a couple of things that could be the reason for a ventilation malfunction and in this article, I’m going to walk you through the steps which will help you get the answer or even fix it. However, if the problem isn’t something you can figure out then you shouldn’t go solo and try the highly technical methods by yourself if you don’t know what you are doing because ventilation systems are really expensive, and in the worst case you could make it even worse. It’s best to call a professional in that case.

Now, let’s see common reasons for ventilation malfunctions and also see the solutions and different methods you could do in order to solve them!

1. Cleanliness

The biggest ”malfunction” is the lack of cleaning and a dirty ventilation system. This should be carefully checked before panicking and calling an expensive professional who comes and says yes, you should clean your ventilation.

There are a couple of things that need to be cleaned that can cause problems with exhaustion and the first and most common are the hood filters. A great rule of thumb is to clean the hood filters once every other week so they remain fresh and clear so the fumes can pass through properly. The hoods that aren’t over grills or other fume-generating appliances don’t require cleaning every other week and can go uncleaned for months.

How To Clean Hood Filters

The easiest and most effective way is to simply clean them in the dishwasher, however, there are a couple of things that need to be taken into consideration before doing that.

First, after removing them from the hood you should spray them with Hood Filter Cleaner and let the chemicals work for 10-15 minutes.

Second, you should rinse the filters with your Faucet before placing them in the dishwasher.

Third, always run them twice in the dishwasher, and

Fourth, don’t forget to change the water in the dishwasher and clean it properly after washing the hood filters. Important note: Always remember to use a face mask and tall plastic safety gloves when handling strong chemicals.

You can also wash them by hand! See steps below.

1. Remove Filters

The first step is to obviously remove the filters however, climbing on greasy countertops is extremely dangerous and for your safety, you should use a Baffle Filter Lifting Tool.

2. Soak In Hot & Soapy Water

The next step is to prepare as hot water as your hands can bear and mix some soap in there as well. You can use long plastic gloves in order to keep yourself clean and handle more heat.

3. Scrub The Filters

Now scrub the filters but do not use a stainless steel scrubber or another scratching scrubber. Instead, you should use a non-abrasive sponge.

4. Dry And Replace

Now that the filters are clean, which can be a little time-consuming and irritating, believe me, I know! You should replace them preferably with the Filter Lifting Tool so you won’t risk yourself falling from the slippery countertops.

2. Exhaust Fan Issues

There are two main issues with exhaust fans that can happen and they are a slow exhaust fan and a reversed exhaust fan. Let’s begin with the first!

Slow Exhaust Fan

If you notice that there’s something wrong with your exhaust fan and see that it just isn’t spinning as fast as it should get rid of the fumes, you should try to increase the amps.

This isn’t as complicated as it sounds and you will need an Amp Meter in order to determine your current amps. After you have the current amps known you should check the vent systems motor or manual for information about how much amp that motor can safely generate. If the number is higher than the number your amp meter shows, you can safely increase your amps!

The way you actually do this is to adjust the motor’s pulley in such a way that it has a shorter rotation distance, therefore faster speed, and more amps!

Reversed Exhaust Fan

This can happen from time to time and you should examine the fan if it’s turning in the right direction, or if the fan’s blades are reversed. If this is the cause then it’s clear why the ventilation isn’t working and you should turn the blades to the proper position or check the manual on how to reset the turning direction.

3. Moisture

When constantly boiling, frying, and grilling the ventilation system can be really long periods under heavy use and that could cause moisture build-ups to form inside the system. Simply turn off the system and see if there are any moisture and water dripping and if that’s the case, just wipe it off carefully and that could solve your problem. Moisture and water will block the exhaust power and that’s why it can seem that the system isn’t working.

4. Motor Problems

The most irritating and painful malfunction is without a question one with the motor included. This can be the hardest or the case can be that you can’t even fix it and then it would be time to get a whole new motor at least.

You can spot a motor problem from unusual noise inside the system, burning smell that is clearly coming inside the vent system, or irregular fan movement. If the case is in the motor it’s best to call a professional so they can determine the issue.

Before calling professionals be sure that you have checked everything that affects the ventilation system and only then call, however, don’t do anything unwise and poke the electrical systems because it could be extremely costly if you accidentally broke something. So in short, check the system thoroughly but don’t become a mechanic overnight.

Can A Restaurant Be Open Without A Hood Vent

The short answer here is no. You should check your local laws and regulations about this because in most areas it is illegal to keep a restaurant open without a proper ventilation system and in worst cases, it could lead to business license termination so don’t risk it before being sure.

How Much Does It Cost To Replace A Range Hood

The prices will greatly vary depending on the type of hood you had in mind, which mounting method will you choose, how much of a CFM do you require, and how big of a hood do you need. An average cost of a range hood is around both sides of $1000 per square foot, however, that includes the installation costs which are usually extremely high. The task isn’t easy for the installing professionals either so it’s always money well spent. You should see our Commercial Range Hood Guide with example range hoods so you could get a better idea of the variabilities between range hoods.


Usually one of the ways shown above will get the air circulating again and the problem isn’t serious most of the time. However, ventilation systems are appliances as the next one and they will malfunction from time to time and eventually get broken.

Remember that if any of the steps don’t work and you can’t figure the reason out, you should definitely call a professional rather than trying to MacGyver your way out of it.

Omar Abdalla

I’m the owner of JRS. While I love writing about food, I also enjoy peaceful and relaxed cookouts at home.

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