Without air conditioning it would be challenging, if not impossible, to live in some of the locations that people today call home. From the high temperatures of Arizona and Dubai to the freezing lows of Canada and even further north. Ensuring adequate thermal comfort during snaps of extreme temperatures is made possible with specialized cooling and heating technology.
This is what we examine today, the technology offered by Hitachi that makes it possible people for to create a comfortable life and a living in places that would otherwise be too extreme.
In this article about comfort in extreme temperatures we:
- Explain what thermal comfort is
- Look at product Temperature Classification
- Explore the technologies that we offer to create comfort in high temperatures
What is Thermal Comfort?
Thermal comfort describes the perceived feeling of hot and cold by a person and is the result of numerous factors including ambient temperature, humidity, air velocity clothing, size, age, fitness level and more. The most common indicator of thermal comfort is air temperature, and when it is too high or too low it impacts mood, productivity, energy and concentration among others, which generally decrease when temperatures rise.
From your home to the workplace and to places of rest and entertainment, indoor thermal comfort is one of the top priorities, which is why it is crucial to manage and control it. According to the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE), the ideal temperature recommend is between 24-27°C during the Summer, and between 20-24°C during Winter. These are subject to factors mentioned above and also personal preference.
When we think of temperatures, we are likely to consider Celsius and Fahrenheit, the most common measurements used around the world. These are used in for thermometers and sensors, and indicate changes in ambient temperatures, both indoors and outdoors, as they rise or fall.
In locations where ambient temperatures are extreme, there is another classification used in conjunction with local climates and air conditioners. A climate class system that ranges from T1 to T3 is used in air conditioning to classify the ambient temperature of different climates around the world and the suitability of a product to operate in that climate.
Ambient temperatures with a T1 class range from -7°C to +43°C, T2 from -7°C to +35°C, and T3 from -7°C to +52°C. As you can see, products of class T1 would be suitable for places with a medium temperature, T2 for lower temperatures, and finally T3 which is most suitable for regions with higher temperatures, like Middle East and Africa (MEA).
Creating Comfort in High Temperatures
For this article, we are turning our attention to the MEA region and the Gulf, where air conditioners that operate in T3 climate conditions are demanded. In this region, the Hitachi PRIMAIRY range of commercial units has been developed to withstand high outdoor ambient temperature, which in T3 climates reach as high as 52°C. The Hitachi PRIMAIRY Ducted and Cassette split units operate in T3 conditions and can operate in 56°C outdoor ambient temperatures. The T climate class rating needs to be taken into account when deciding on your Hitachi air conditioning system to provide climate control that functions properly and, above all, safely.
One of the most important aspects of the Ducted and Cassette split's ability to operate in such extreme temperatures is that they can work 56°C heat without tripping or producing any technical issues. This means that the operator can enjoy consistent and interrupted comfort to their customers, increasing the positive experience offered by their business.
Within the global PRIMAIRY range, we go to lengths to deliver products with high protection. In regions like MEA, a Gold Fin protective coating is used to protect the condenser coil in the outdoor unit, reducing the effect of corrosion in high ambient temperatures and humidity. In other regions, a different protective coating that provides the same benefit is used however more apt to the different climates.
To protect the system further and support performance, high pressure (HP) and low pressure (LP) sensors protect the compressor and refrigeration circuit, as well as a refrigerant leak sensor and special microchips with pre-loaded data.
The HP switch monitors the system’s outdoor motor and the condition of the condenser coil. The LP switch, on the other hand, monitors the refrigeration circuit for loss of refrigerate in the system, which may lead to frost on the indoor unit’s evaporator coil. If one of the switches trips, the unit self-diagnoses and offers an error code to help detection and solution a rapid process.
Similarly, the VRF units we offer in the MEA region and the Gulf that, depending on which countries, operate in T3 climates and offer cooling in outdoor ambient temperatures up to 46°C. There is a T4 climate class in Kuwait which has an operating temperature of 48°C.
The VRF JNBBQ series uses a combination of intelligent compressor design and system controls that enable it to expand its operational temperature range to up to 54°C. This, like the PRIMAIRY units, means that they can withstand extreme high outdoor ambient temperatures to provide consistent performance and comfort. They also come with an optional anti-corrosive coating, designed to withstand exposure in saline rich environments.
In India, our lineup is designed with the country’s climate and ambient temperatures in mind. For example, our residential inverter air conditioner Kashikoi series offers better humidity control and faster cooling, increasing the comfort of users. Its design stems from our Tropical Inverter Technology, which uses a unique variable speed tropical compressor that varies its RPM by adjusting the power supply frequency.
This is achieved by Seamless Cascade Vector DC Inverter System that comes pre-installed with a micro-computer which controls its rotation, providing cooling solutions as per the room’s requirements. This also ensures that it can provide 100% cooling performance even in extreme Summer conditions up to 43°C.
It’s these technologies that make comfort in high ambient temperatures a possibility. Of course, within our product range we also have innovative products that provide consistent comfort in the bitter cold. For example, our commercial air conditioners designed for use in North America can operate without reducing performance in as low as -15°C. We will explore the technology we have developed for lower ambient temperatures in our upcoming post.
At Hitachi Cooling & Heating, we pride ourselves on the adaptability of our products crafted for different ambient temperature conditions around the world. To see how we can help create the optimal level of indoor comfort wherever you are, visit our main website and see which product range suits your needs best.
Johnson Controls-Hitachi Air Conditioning