🍳 Why Kitchens Get So Hot: A Quick Story

Picture this: You’re cooking dinner on a summer evening. The oven is cranked up, burners are blazing, and your kitchen feels like it has its own weather system. You open a window—but the heat lingers. You turn on a fan—but the smells stick around.

The real culprit? Poor ventilation.

Kitchens create:

• Heat

• Steam

• Grease particles

• Smoke and odors

And unless these are removed efficiently, they build up and strain your HVAC system—sometimes to the point where a portable AC feels like the only solution.

🌬️ How Vent Hoods Keep Kitchens Comfortable

Your kitchen’s range hood is a superhero disguised as an appliance. Its job is to pull cooking byproducts out of your home, improving both indoor air quality and temperature control.

Two Types of Range Hoods

1. Ducted (Vented) Hoods

These pull air directly out of your home through metal ducts.
Pros:

• Best for heat removal

• Removes smoke, steam, and grease effectively

• Helps your HVAC system maintain better indoor balance

Cons:

• More expensive to install

• Requires proper ductwork

2. Ductless (Recirculating) Hoods

These filter air and push it back into your kitchen.
Pros:

• Easy to install

• Budget-friendly

Cons:

• Doesn’t remove heat

• Can disrupt HVAC balance by recirculating warm air

If you’ve ever wondered why your kitchen feels hotter even after installing a hood, it may be because you’re using a ductless model that simply can’t remove heat from the space.

🌡️ How Range Hoods Affect HVAC Balance

Your HVAC system is a delicate ecosystem. When a range hood exhausts air from your kitchen, the home must replace that lost air—this is called makeup air.

Without proper makeup air:

• Your HVAC system may pull unconditioned air from outside

• Negative pressure can form inside the home

• Your portable AC (or central AC) has to work harder

A too-powerful hood can even backdraft combustion appliances by pulling air backward through vents—a serious safety concern.

So while a portable AC may help cool things down, it can’t fix an underlying ventilation imbalance.

📏 Sizing Guidelines for Vent Hood HVAC Kitchens

Choosing the right hood size isn’t just about looks—it’s foundational for airflow and kitchen comfort.

1. Sizing by Stove Width

The hood should be at least the width of your cooktop:

• 30-inch stove → 30-inch hood

• 36-inch stove → 36-inch hood

For better capture, some prefer adding 3” on each side.

2. Sizing by CFM (Cubic Feet per Minute)

This is where HVAC balance truly matters.

General Rule:

100 CFM for every 10,000 BTUs on your stove.
Example:
If your cooktop outputs 50,000 BTUs → 500 CFM hood recommended

Gas vs Electric

• Gas ranges require more CFM because they burn hotter.

• Electric ranges can get by with smaller systems.

High-Output Cooktops

Professional or semi-professional gas stoves often demand 600–1200 CFM.

3. Don’t Forget Makeup Air Requirements

Many building codes require makeup air for hoods over 400 CFM.
This ensures:

• No negative pressure

• HVAC systems stay balanced

• Indoor air quality stays stable

Think of makeup air as the “replacement air” your kitchen needs to work properly.

❄️ So… Is a Portable AC Worth Buying?

A portable AC can help cool your kitchen temporarily, especially:

• In older homes without good ventilation

• When cooking for long periods

• In apartments where ductwork can’t be modified

But it’s a Band-Aid, not a cure.

A well-sized, properly ducted, balanced vent hood HVAC kitchen setup offers:

• Long-term comfort

• Better heat removal

• Less strain on your AC system

• Improved indoor air quality

If your kitchen gets unbearably hot during cooking, addressing ventilation first is usually the smarter investment.

🧠 Conclusion

Portable ACs can be useful, but they aren’t the first—or best—solution for a hot kitchen. Proper hood sizing, makeup air, and good ventilation design play a far bigger role in comfort and HVAC efficiency.

If you handle the ventilation, you may not need that portable AC at all.

❓ FAQs

1. Can a portable AC cool down a kitchen while cooking?

Yes, but it won’t remove heat at the source. A range hood is more effective.

2. How much CFM do I need for my range hood?

Use 100 CFM per 10,000 BTUs as a guideline.

3. Do ductless range hoods affect HVAC balance?

Yes. They don’t remove heat and can make kitchens feel warmer.

4. What is makeup air, and do I need it?

Makeup air replaces exhausted air. Hoods above 400 CFM often require it.

5. Will a bigger hood improve HVAC comfort?

Not always. Oversized hoods can cause pressure imbalance without proper makeup air.

6. Can improper ventilation damage my HVAC?

It can increase energy use, reduce efficiency, and cause airflow issues.

7. Are ducted hoods better than ductless?

For heat and smoke removal—absolutely.

8. Does range hood placement matter?

Yes. Hoods should be 24–30 inches above the cooktop for best performance.

9. Can a portable AC and range hood run together?

They can, but high-CFM hoods may overpower the AC by exhausting conditioned air.

10. What’s the best long-term solution for hot kitchens?

A properly sized, ducted range hood with balanced makeup air.