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Commercial Air Conditioning, Commercial HVAC, Commercial Installations

Essential Equipment for Commercial Kitchens: HVAC Make Up Unit


restaurant make up air unit

Have you ever noticed an oily odor from your frying pans and other smells from the cooking process lingering long after the chefs retire their aprons for the night? Does it seem like it takes too long for smoke from the grill, the stove and steamy pots and skillets to dissipate?

These problems are likely the result of your exhaust fans sucking the air from your kitchen space, but not enough air replacing the exhausted air. By outfitting your kitchen with a restaurant make up air unit, you can avoid these suffocating problems.

Why install a restaurant make up air unit?

Like most residential kitchens, commercial kitchens are outfitted with an exhaust fan. It is not uncommon for commercial kitchens, which have a varied array of kitchen appliances that generate smoke and steam, to have more than one exhaust fan. So what’s the problem then? Your mighty restaurant-grade exhaust system might actually be sucking too much air from your kitchen space.

These fans can remove 100 cubic feet of air per minute. When all that air is extracted from your kitchen, it needs to be replenished by an equal volume of fresh air to maintain good air quality.

This year, due to the risk of COVID-19, proper ventilation and air quality are more important than ever. Especially if you have upgraded to MERV 13 HVAC filters, those filters may have further decreased the level of air flow.

So how do you compensate for the air lost from kitchen exhaust? Some replacement air is transferred from other nearby rooms such as a dining room. If an HVAC system is properly designed, roughly 10-percent of replacement air will transfer from adjacent rooms. So, where does the remaining 90-percent of replacement air come from? You install a make up unit.

Let’s take a look at the problems that result from inadequate ventilation in your kitchen and how a restaurant make up air unit can help.

10 kitchen air quality symptoms you can cure with a make up unit

1. Unappealing odors straying from the kitchen
By installing a restaurant make up air unit in your kitchen, you will increase your control over airflow, which will give you the ability to stop unsavory cooking smells from seeping into your dining area. You certainly don’t want distasteful smells to interfere with an enjoyable dining experience.

Learn more: Are Indoor Odor Problems Driving Your Customers Away?

2. Fumes & poor air flow
Your kitchen staff should be able to see clear across the kitchen and not have to squint through a haze of cooking fumes. If not enough replacement air is coming into your kitchen, it means not enough air will be sucked into the kitchen exhaust hoods. This will result in the buildup of negative pressure (more on this in a minute) and reduced exhaust flow, which will and impede the exhaust hood’s ability to capture and contain kitchen fumes.

Never ignore air quality issues because they affect the health and safety of your staff. We’re betting you cannot afford increased employee absenteeism and decreased productivity because of air quality issues.

3. Negative air pressure
Negative air pressure can result in a negative dining experience and negative work environment. What is it? An imbalance of air pressure can produce cross drafts, which will do nothing for the dining or work experience at your business.

You might notice doors that swing inward are hard to close and doors that swing outward are difficult to open and have a tendency to slam shut. These door problems are occurring as drafts of air are sucked in from a compromised door seal. Air will be pulled in from open windows or any cracks or holes leading to the outside. Dirt and dust will be sucked in from the bottom of doors that are not tightly flush with the ground. Besides slamming doors haunting your diners, a dust bowl blowing through is not likely the ambience they are looking for at your dining establishment.

Learn more: HVAC Troubleshooting: Surprising Symptoms of HVAC Problems

4. Cold walls
Without a make up unit, the air imbalance makes your perimeter walls cold. Insulation will not be totally effective when faced with the drafts of air being sucked inward. Your customers won’t appreciate those uncomfortable spots in your dining room.

5. Moist walls
When you have a negative air pressure problem, fans will pull in moisture. If you have cement or stucco perimeter walls or if your walls are made out of some other masonry material, outside water will be pulled in via any small cracks that have developed. Unwanted moisture can lead to mold and mildew growth: the last thing you want in a commercial kitchen.

6. Back drafting
If there is negative air pressure, back drafts could prevent dangerous carbon monoxide and noxious vapors from gas ovens, grills and wood-fired ovens from escaping up chimneys, flues or draft stacks. Besides being a potentially unhealthy breathing experience, it could result in carbon monoxide detectors going off, which could mean you’ll have to evaluate your restaurant during a busy dinner shift. Installing a restaurant make up air unit could help you prevent a dining disruption that could damage your restaurant’s reputation.

7. Exhausted exhaust hoods
A lack of make up air might be straining your exhaust hood. The reduced air supply causes an increase in static pressure, which lowers the cubic feet per minute of air that your hood can remove from the kitchen. If the air supply is depleted the exhaust fans shutters might not fully open. You might also notice that your exhaust hood is showing signs of corrosion because it can’t thoroughly suck up corrosive fumes. Remnants of these corrosive elements remain on the hood and cause damage.

8. A greasy kitchen
Because your exhaust system can’t work effectively without a make up unit, you might notice more grease clinging to the surfaces of your appliance and countertops. This will result in your staff spending more time on cleaning detail.

9. HVAC consequences
When chimneys and flues lose the ability to draft properly because of poor airflow, the consequence could be heating system problems. Pilot lights may go out and stacks and heat exchangers could become damaged.

10. Higher energy bills
Without outside air being pulled into the kitchen by a make up unit, your HVAC system must work longer to maintain set thermostat temperatures. This will result in higher utility bills. The installation of a make up unit will ensure adequate air supply, balanced air pressure, and lower expenses at the same time.

COVID and another air quality option to consider

Restaurants need to make their spaces as safe as possible for diners. The improved ventilation provided by a make up air unit is one step that can help with that, since experts say adding ventilation can help to prevent the spread of the virus.

However, there is more you can do. Certain types of air purification devices can be installed within your HVAC system that have been proven to kill 99.9% of COVID-19 particles in the air and even on surfaces. You can read more about these air purification devices here, and request a consultation to find out if adding this technology is a good choice for your restaurant.

Need a restaurant make up air unit? What to do next

If you have been plagued by any of these problems in your restaurant, consider installing a restaurant make up air unit to ensure an adequate air supply. Your rewards for investing in a make up unit will include improved air quality, a cleaner environment and better comfort conditions for your customers and employees.

Choosing the right HVAC company to design a restaurant make up air unit is critically important. You want one with extensive experience working with food service environments, as well as experience in the type of building you’re in, whether that’s a high rise, a mall or a standalone structure. Find out what you need to consider from this helpful resource: The NYC Restaurant Owner’s Guide to Choosing an HVAC Company.

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