How much heat does a commercial refrigerator give off?

We all know that commercial refrigerators give off heat. After all, when you remove the heat from inside the refrigerator, it must go somewhere. But how much heat is a different question. It can vary greatly, according to different contributing factors.

You must also be aware of the implications of this heat, and the steps you can take to mitigate any negative effects it may cause. This blog takes a closer look at how much heat a commercial refrigerator generates and what you can do to minimise the impacts on your business and customers. Let’s dive in.  

How does a commercial refrigerator work?

Refrigerators work not by adding coldness to the interior, but by removing and expelling heat. Heat transfer in a commercial refrigerator – or any typical refrigeration system – operates on the principles of thermodynamics.

The refrigeration cycle begins with the compressor, which, as its name suggests, compresses the refrigerant gas. This compression increases the pressure and temperature of the refrigerant.

The hot, high-pressure gas then flows through the condenser coils located on the outside of the refrigerator. Here, the refrigerant releases its internal heat to the surrounding environment (outside the refrigerator), cooling down and condensing into a liquid as it loses heat. This is why the back of a fridge usually feels warm.

The now liquid refrigerant, still under high pressure, travels through an expansion valve. When it passes through, its pressure drops sharply and it cools down further. This sudden drop in pressure causes the liquid refrigerant to cool and partially evaporate, transforming into a low-temperature, low-pressure mixture of liquid and gas. This cold refrigerant mixture then enters the evaporator coils inside the fridge or freezer compartment. As the refrigerant absorbs heat from the interior of the refrigerator, it evaporates (from a liquid to a gas), removing heat from the air inside the fridge. This process cools down the contents of the refrigerator.

The refrigerant, now in its gaseous state and containing absorbed heat from the fridge’s interior, is sucked back into the compressor, and the cycle repeats.

The heat transfer process is an ongoing cycle while the refrigerator is in operation. The cycle is efficient, continuous and designed to maintain a consistent, cool temperature inside the fridge.

Not all fridges are created equal

You may notice that some fridges seem to produce more heat than others. This is due to several factors. Small fridges need to remove only a small amount of heat from the inside, whereas large display fridges, like multidecks or uprights, need to remove a large amount of heat. Larger appliances will always produce more heat, as there’s more heat inside them. Some fridges are extremely efficient and remove the heat inside very well, whereas others are not so good, and won’t transfer as much heat. The difference in temperature between the outside and inside temperatures will also make a huge difference in the amount of heat being transferred. If the ambient temperature is cold, there won’t be as much heat energy inside the fridge to be transferred, so you won’t feel much heat being sent out of the back of your fridge. However, if it’s a hot day, the fridge will need to remove far more heat energy to bring the air down to the correct temperature. This heat will then be emitted from the fridge. If you have a busy commercial kitchen or retail environment and your fridge door is continuously being opened, the ambient temperature inside the fridge will keep warming up. This constant increase will mean more heat needs to be transferred to the outside. If the door remains closed, once the fridge is brought down to temperature, it will find it easier to maintain the temperature inside the fridge.

What happens to the heat?

We know the heat is transferred out of the fridge. If you put your hand behind a fridge, you’ll be able to feel the heat energy being released. But where does this heat go? Remember, you can only transfer heat energy, not get rid of it. So, if you keep pumping heat energy into a small room it will get hotter and hotter. If you go into buildings that run multiple fridges or freezers in the summer, they can be extremely uncomfortable. Bear in mind that if you have a business and employ people, you have a duty of care towards them. If you have customers in the same room as your refrigeration units, you want to ensure they’re comfortable. Even simple solutions such as opening windows and doors to increase ventilation will help to dispel the extra heat. Remember, it’s essential to have sufficient space around the back of your refrigerator so that there’s enough room for the heat energy to escape. Consider the placement of your refrigeration units to aid ventilation and prevent excessive heat build-up.

Drawbacks of heat transfer

Commercial refrigerators generate a significant amount of heat. If it isn’t effectively managed or vented out of the retail space, it can lead to an increased ambient temperature. This escalation often leads to using additional air conditioning or ventilation to keep your room cool, increasing energy consumption and costs.

Higher energy usage not only affects costs but also contributes to a larger carbon footprint. Given growing consumer awareness and concern about environmental sustainability in the UK, this can impact your brand’s reputation and customer appeal.

UK businesses are increasingly subject to strict regulations aimed at reducing energy consumption and mitigating climate change. Inefficient heat handling could make it harder to meet these regulatory standards and targets.

Excessive heat can create an uncomfortable shopping environment for customers and a challenging work environment for staff. In the UK, where many buildings, including retail spaces, aren’t designed for extreme heat, this can be particularly problematic during warmer months or in shops with limited ventilation.

If the heat from commercial refrigeration units raises the temperature in certain areas of your store, it might impact the quality and safety of temperature-sensitive products. This issue is crucial in food retail, where maintaining strict temperature controls is essential for complying with food safety standards and ensuring product quality.

The need to adequately ventilate and manage heat output can dictate store layout and design, potentially reducing space use and efficiency. This constraint is particularly relevant in urban UK retail spaces, where floor area is often at a premium.

And refrigeration units that constantly work hard to cool in a heated environment may experience increased wear and tear. This can lead to more frequent maintenance requirements and potential downtime, impacting business operations and incurring additional costs.

How to mitigate the impacts of refrigerator heat

Retailers must balance their operational needs with staff and customer comfort and their energy consumption and environmental impact. There are several steps you can take to mitigate the heat produced by your refrigeration units, ensuring efficient operation while maintaining a comfortable shopping environment.

Enhancing the ventilation around refrigeration units helps dissipate the heat they emit. This can be done by ensuring sufficient space around the units and using ventilation systems to expel warm air outside the shop.

Positioning refrigerators away from heat-sensitive areas (such as produce sections) and keeping them out of direct sunlight can reduce their overall thermal impact. Placement should also consider customer comfort and the flow of shopping traffic.

Regular servicing of your refrigeration units ensures they operate at peak efficiency. This includes cleaning condenser coils, checking the thermostat and ensuring the door seals are intact. Efficient refrigeration units emit less heat.

Investing in newer, more energy-efficient refrigeration technology can be more effective in managing heat output. Modern refrigerators often come with better insulation and more efficient compressors and coolants, reducing the heat they emit.

Some advanced refrigeration systems come with heat recovery options, which use the waste heat for other purposes like warming water, reducing overall energy consumption.

In non-operational hours, using night blinds on open refrigeration like multidecks can help maintain the temperature more efficiently, reducing the amount of work the units need to do and the heat they emit.

Improving insulation in and around the refrigeration units can also help contain and minimise the heat they emit into the retail space.

In larger retail spaces, creating zones where cooler and warmer temperatures are managed independently can help. This zoning allows for more strategic air conditioning use and keeps heat-sensitive products away from the warmer zones.

Educating your customers about the reason behind the warmth near refrigeration units can also be helpful. This awareness can enhance their shopping experience by reassuring them that the heat is a normal by-product and that you’re taking steps to manage it effectively.

TEFCOLD can help and advise on the best refrigerator for your business

Here at TEFCOLD, we can advise you on the best refrigerator for your business. If you want to upgrade your current unit or expand your business, we have an excellent range of quality display refrigerators. We pride ourselves on the quality, design and craftsmanship of all the units that we supply. If you’re looking for help or advice on your commercial refrigeration, we’re here to help. Simply call our experienced team today on 01332 850090.