Currently Browsing: Design

air ceiling registers

How do replacement air ceiling registers affect the hood?

The placement and location of ceiling registers (diffusers) for the introduction of replacement air can have a direct impact on the proper operation of the exhaust hood. Diffusers that have been designed for commercial spaces, such as “four way diffusers” were developed to have a high induction capability. That means they discharge at a relatively […]

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Gas burning in the burner of gas oven

Why is a heat load based design important for kitchen hoods?

Establishing exhaust volumes for hoods had been an inexact science, primarily relying on U.L. values to establish exhaust rates. U.L. however clearly states that the minimum exhaust rates established during testing should not be used for design purposes since they were achieved in a laboratory environment. A greater exhaust might be required to provide proper […]

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Kitchen Ventilation Cooking Equipment

Why is cooking equipment makes and models important for preliminary engineering?

Outdated methods of ventilation design categorized appliances into different classes of light, medium, heavy duty and extra heavy duty (solid fuel). Average exhaust rates were established for each category based on rules of thumb, cfm per foot of hood. With the advent of U.L. 710 test, this morphed into minimum exhaust per surface temperature (400° […]

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SupplyAir

What temperature should the supply air be introduced to the Kitchen?

Engineers will typically design for a supply air temperature at 10 degrees above traditional occupied spaces outside of the kitchen. Supply air is usually brought into an occupied space at 57°F/14°C off the coil to mix with room air to maintain a specified space temperature at design conditions. In a kitchen, due to the air […]

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