Keeping Things Comfortable in the Kitchen: Latent & Sensible Heat

March 26, 2019 by Hobart


Controlling Latent and Sensible Heat from the Dishroom

When it comes to kitchen operations, temperatures are a key ingredient.  Refrigerators should be set at 40 degrees or below and freezers at 0 degrees or below. Hot food should be served at 140 degrees or warmer and cold food served at 40 degrees or colder. But what about the temperature of the kitchen itself? We know that temperature in the workplace is as important for productivity as food temperatures are important for food safety. “Studies show that as little as a two degree difference can affect productivity,” says Keven Hass, national sales manager, Gaylord Industries. Hot, humid environments can make people irritable and sluggish, and could even lead to heat sickness.

Commercial dishwashers are just one of many pieces of equipment in the kitchen that can affect the comfort level of the work environment. The speed and efficiency in cleaning dishes comes from high temperatures and lots of water, that turns into steam. Luckily there are ways to control the heat and humidity produced by dishwashers and keep your kitchen comfortable and productive.

Understanding Heat

In order to understand how to best control the environment surrounding a commercial dishwasher, it’s important to first understand the heat output.

  • Sensible Heat. Sometimes referred to as radiant heat, this is the warmth produced by the equipment that radiates out into the environment and can raise the temperature, like the radiant heat of the sun warms the temperature of the Earth. Sensible heat is the warmth you feel when standing in front of the dishwasher.
  • Latent Heat. This is the energy released when water changes to steam, without a change in the actual temperature. Humidity itself isn’t latent heat, but it contains latent heat. When an environment is humid, it can feel hotter than the thermostat says, because a thermostat only measures sensible heat.

Keys to Comfort

There are many elements to consider when working to create a pleasant atmosphere around your commercial dishwasher. With a full understanding of the different steps you can take, you can enjoy the efficiency and high productivity of commercial dishwashers without any adverse impact on your work environment.

  • Kitchen Design. The design of the kitchen is important when creating a comfortable workplace. A dish room with ample space for employees to move around, high ceilings and proper ventilation helps keep the air flowing and temperatures at a comfortable level.
  • A properly sized HVAC unit plays an important role in environmental control. A unit that is too small might not be able to cool the area to the temperature set on the thermostat, while a unit that is too big will cool the room temperature down so quickly that the unit doesn’t have time to also remove the latent heat, leaving the atmosphere uncomfortable. Work with your construction engineer to properly size the HVAC system for your particular load, which takes into consideration the size of the room as well as the equipment within the working space.
  • Incoming Air. In addition to controlling the temperature of the room, it is important to heat and/or cool the air that is being pumped into the dish room. “The mechanical engineer should take this into account when designing a kitchen, because code states the difference between make-up air and the air in the room should not exceed 10 degrees,” Keven says. This means the air should be heated on entry during the winter months in most places, when the outside air is much cooler than the air inside. But it also means operators should consider cooling make-up air during the summer months, especially in hot and humid locations.
  • Proper Hood Installation. Certain types of dishwashers, including conveyor and flight-type, require a Type II hood to help remove steam from the dish room. When specifying a hood for your commercial dishwasher, take into account the amount of overhang that will be necessary to completely cover the discharge space where the racks come out or where the door is “For conveyor dishwashwers I recommend a larger overhang on the discharge side to account for the exhaust where the racks come out,” Keven says.
  • Ventless Dishwashers. Some dishwashers do not need a hood to keep the dish room at comfortable working temperatures. Hobart’s Advansys™ line of dishwashers incorporate an energy recovery system with condensing cycle that captures the steam from the wash cycle and condenses it to heat incoming cold water. Not only is less energy needed to heat the water to appropriate temperatures for the next cycle, but less latent heat is released into the dishroom environment. In one case study in Troy, Ohio, a kitchen ran 125 cycles in a ventless dishwasher between 5 and 10 p.m. During that time the average relative humidity in a central area of the kitchen was about 44 percent, while the relative humidity over the machine was about 56 percent, well under the industry standard of 65 percent relative humidity.

Call your local Hobart representative to learn more about how a commercial dishwasher can improve operations in your kitchen, and how to integrate it into your workflow while maintaining a comfortable dishroom environment for your staff.

See our full line of Commercial Dishwashers

Tags: Dishwashing


Latest Posts

Choosing Disposable or Reusable Ware for K12 Food Service

April 01, 2022 by Hobart

Each year, an estimated 7.5 to 8 billion breakfasts and lunches are served to K-12 students across the United States. The type of ware used to serve those meals in some ways is just as important as the food that’s on it, and plays a big role in determining the budget, labor needs and waste management for a food service operation.

Many school systems relied on disposable ware programs during the height of the COVID-19 pandemic, even if they had a reusable ware program before the pandemic. Disposables made it easy to package and deliver to-go meals to students doing remote school and helped address concerns over contamination for on-site education. Now as we emerge from COVID-19 restrictions, K-12 food service is being impacted by additional factors including budgets, availability of supplies and storage space, labor costs, and sustainability expectations and mandates. Many schools are reconsidering their ware programs and making the switch to reusables.

Read More

Even Greener Than Before - Commercial Dishwashers & ENERGY STAR 3.0

July 09, 2021 by Hobart

Effective July 27, 2021, all commercial dishwashers sold with the ENERGY STAR label will have to meet new, more stringent guidelines and testing requirements set by the ENERGY STAR program, a joint program between the U.S. Environmental Protection Agency and the Department of Energy. Hobart is ready with dishmachine models from across our entire product line that are certified to the new standards. 

Read More

What’s Your Time Worth? Reducing Labor in the Dishroom

April 06, 2021 by Hobart

Time is money, and no one understands that old adage more is better than an employer who pays employees by the hour. What if there was a way to reduce the amount of time dishroom operators have to spend pre-soaking and scraping dishes before loading them into the dishmachine, and instead gives them more time to do other productive tasks around the kitchen? The Automatic Soil Removal (ASR) technology on select Hobart commercial dishwashers reduces time spent prescrapping, leading to dishwashing labor savings by 20% or more.

Read More

How Clean are Your Dishes? Cleaning Tough Foods with Less Effort

March 25, 2021 by Hobart

Anyone who has spent time soaking and scrubbing dried-up, crusty foods and grease off dishes, prep ware and pots and pans knows just how tough and time consuming some foods soils are to remove. Some of the top offenders are eggs, cheese, pie filling and tomato-based sauces, and anything with a high sugar or fat content is a prime culprit in baked-on, dried-up or greasy food messes.

Thanks to these tough foods, scrapping and soaking are necessary processes in the dishroom. But with the right equipment in place the time spent on these labor-intensive tasks can be reduced, leading to increased productivity and cost savings in the kitchen.

Read More

Head of the Class Performance: Hobart Dishwasher Serving School Since 1965

March 11, 2021 by Hobart

Since 1965, Roncalli High School of Manitowoc, Wisconsin, has been preparing students for life – 5,118 graduates so far, and about 230 current students.

And since the first day of classes at Roncalli High, a Hobart C-81 conveyor-style dishwasher has been reliably washing students’ lunchware, 180 days a year, going on 56 years. Not to mention cleaning dishes to a sparkle after the school’s annual Food Fair, annual dinners, fundraising auctions, and even community events and wedding receptions.

Read More