It is naturally inevitable to use air conditioners for server room projects. When choosing air conditioning equipment for the cooling system of a data center, there were once many data center IT personnel who thought that ordinary air conditioners could also be used for cooling the server room. They thought that ordinary air conditioners had high energy efficiency and therefore could reduce the energy consumption of the cooling system.
As we all know, usually 30% of the ordinary air-conditioning cold load is to eliminate latent heat load, 70% is to eliminate sensible heat load. Precision air conditioning, the situation is very different, mainly to eliminate the machine room equipment dispersal of sensible heat, indoor staff dispersal of heat load and fresh air into the room in the summer of the heat and humidity load (accounting for only 5% of the total load). This determines that they will be different from the design purpose, application scenarios, functional focus, etc..
This blog explains the differences between precision air conditioners and ordinary air conditioners from five aspects: basic concept, product focus, control system, air filtration, operational performance and cost.
Different basic concepts
Ordinary air conditioning generally includes domestic air conditioning, central air conditioning in residential areas and air conditioning systems in offices and commercial office buildings. The role of this type of air conditioning is to cause indoor air with a good living environment, to provide people with a comfortable and cozy working and living environment, so that people in this space feel comfortable.
Precision air conditioning is designed to meet the requirements of special processes and specific environments for precision equipment, with the aim of accurately controlling its temperature, humidity, etc. and requiring control within a certain range, also known as constant-temperature and constant-humidity air conditioning, characterized by a large amount of airflow and heat load changes.
The focus of the product
The focus of the product will be very different depending on the purpose for which it is designed.
Ordinary air conditioners are designed to “provide people with a comfortable and cozy working and living environment”. It is applicable to the object is human, the application of the scene is mainly in the semi-open area of human activities: such as living rooms, bedrooms, exhibition halls, offices and so on. Ordinary air conditioners do not have the function of “constant temperature and humidity”, and the temperature difference range is 1℃. Therefore, ordinary air conditioners pay more attention to the use of comfort, low noise, low air volume and low wind speed design.
Precision air conditioners are designed to “provide a specific operating environment with constant temperature and humidity for IT equipment and other precision devices”. It is a high-precision air conditioner designed for use in computer rooms to ensure good heat dissipation from computer or server chips, and is used in high-precision areas such as computer rooms, laboratories, and large medical equipment rooms. Its service object is to maintain the computer room can continue to run up the relevant equipment: such as IT equipment, power distribution systems, power supply equipment.
Precision air conditioning has the function of “constant temperature and humidity”, and the range of temperature difference can be controlled at 0.1 degree Celsius or even higher. Therefore, precision air conditioners pay more attention to the precise control of temperature and humidity in the machine room and the design of timely control of cleanliness.
Different control systems
Ordinary air conditioners only have a basic control system, people according to their own hot and cold needs, through the infrared remote control or download the cell phone APP smart remote control operation, the degree of intelligence is relatively moderate; and cooling and dehumidification can only be carried out at the same time, and can only be in the direction of the air supply local airflow circulation.
Precision air conditioning has a high-precision, responsive, microprocessor-based intelligent control system, which can respond quickly to changes in the external environment, thus ensuring that environmental changes remain within the adjusted range required to stabilize the environment. For example, human-computer interactive interface, alarm protection, network monitoring and other functions.
Different degrees of air filtration
Ordinary air conditioners use coarse filter, can not remove enough dust particles, dust will be attached to a large extent in the efficient operation of the chip, seriously affecting the service life of the relevant parts, is unable to meet the purification requirements of the computer. Most ordinary air conditioners use residential air filters, the filtration efficiency is only 10%. This is far from enough for the data center environment.
Precision air conditioners use high-middle efficiency filters, the efficiency of which can reach 20% to 30% and meet ASHRAE standards, can filter out the dust in the air in a timely and efficient manner, can effectively prevent dust in the high-frequency chip attached to the carbonization caused by the short-circuit, to maintain the cleanliness of the server room, extend the service life of the relevant parts, and reduce the cost of operation and maintenance.
Differences in operating performance and costs
The ordinary air conditioners used in most office buildings run for an average of 8 hours a day, 5 days a week, while some commercial premises, such as supermarkets and shopping malls, run for an average of up to 12 hours a day, 7 days a week. Sometimes also encounter environmental changes or special needs, and increase the running time. For precision air conditioning, regardless of the external environment, most data centers require 365 days a year, 24 hours a day uninterrupted operation.
And those ordinary air conditioners with outdoor heat exchangers generally cannot operate when the external ambient temperature drops below 32°F due to low pressure. However, precision air conditioners can operate normally at -30°F, while glycol cooling systems cool normally at -60°F.
The scope of application of precision air conditioning
Machine rooms and laboratories in the electronic information industry: it is necessary to provide a low humidity, stable temperature and low vibration operating environment for precision electronic equipment to ensure the normal operation of precision equipment and reduce the failure rate.
Life science industry laboratories, cell culture conditions: the need to provide constant temperature precision air conditioning environment, to ensure that cell culture and life experiments in constant conditions, such as product temperature or humidity fluctuations can not exceed ± 1 ° C .
VOC online monitoring equipment in the environmental protection industry: need to accurately measure and monitor the content of toxic substances in the air, relying on high-precision constant temperature and humidity air-conditioning equipment as the monitoring of the pre-processing link to ensure the accuracy of the measurement results.
Tray and laser production environment in semiconductor industry: Adoption of atmospheric purification system and constant temperature and humidity system provides ultra-clean and ultra-stable environment for the production of precision laser and silicon wafers, and reduces the risk of contamination of products by dust particles.
Although precision air-conditioning is basically much higher than ordinary air-conditioning in terms of initial investment. However, the annual operating cost of an ordinary air-conditioner is higher than that of a precision air-conditioner by $243 per cooling ton of sensible cooling capacity. This is consistent with the industry’s generally accepted principle that 3 cooling tons of ordinary air conditioning is equivalent to 2 cooling tons of precision air conditioning.
Therefore, for those small projects, in the case of sufficient funds, it is recommended to combine the initial investment, operating costs of the two cases and then consider; in some large-scale projects, it is recommended that the use of precision air conditioning, its uninterrupted operation throughout the year design, intelligent control system, constant temperature and humidity, components and redundancy features, which will greatly improve the reliability of equipment operation in the later stage will greatly reduce the operation and Operation and maintenance costs.