Air conditioning of server rooms: features of choosing an air conditioner

To accommodate internal information systems, the company allocates a separate room - a server room. It houses computers, computers, servers and other telecommunications equipment. The room has strict requirements for climatic parameters: humidity and temperature. The installation of air conditioners provides optimal conditions for the operation of equipment. The type and capacity of the air conditioner is selected taking into account the characteristics of the server room.

Purpose of air conditioning in server rooms

Equipment layout diagram in the server room

The server room is a room for telecommunications equipment. The room is equipped with a backup power supply, temperature and humidity sensors. The room has no windows. The operating equipment generates a huge amount of heat, the air conditioning system is responsible for its removal. It must provide a favorable environment for the servers. High temperature and dust in the air can damage sensitive equipment. It is the task of the climatic device to bring the indicators to the normative ones.

Features of server rooms

Choosing an air conditioner for server rooms, take into account the specifics of the premises and the basic requirements for them:

  • Climatic equipment must work continuously, around the clock, 365 days a year.
  • The optimum temperature is 18-25 ° C.
  • Air humidity indicator in the range from 20% to 80%. In winter, 75-80% is allowed, in summer - no more than 65%.
  • The amount of dust is up to 0.75 mg / m3, the particle size is not more than 3 microns.
  • The optimum air flow speed is 0.2 m / s, fluctuations in the range up to 0.5 m / s are allowed.
  • The noise level is not higher than 65 dB.

Based on the characteristics of the room, air conditioners must control the level of humidity, temperature and dustiness.

Recommendations for choosing the type of air conditioner

Server cabinet air conditioner

Difficult operating conditions with continuous load are not able to withstand every climate system. It must be equipped with a dust filter, dehumidifier, winter kit. One of the options for air cooling is an air-conditioned server cabinet. The design does not require condensate drainage, the outdoor unit is compact in size. The indoor unit is installed vertically or horizontally inside a server cabinet.

Requirements for air conditioners

When maintaining the climate in the server rooms, the smooth operation of air conditioners is important. Breakdown and repairs will leave telecommunications equipment uncooled for a long time. The principle of rotation and reservation allows the requirement to be met. Several climate control units are installed in the room, connected into one network by a rotary device. In the event of a malfunction of one air conditioner, the backup option is automatically activated.

The alternating switching on of the blocks allows you to balance the load and ensure optimal climate parameters. In this mode, the technician stops alternately for rest and maintenance.

The rotation unit helps to control the air conditioning of the server rooms.It automatically alternates the switching on of working units, if necessary, connects a backup device. The second control option is the installation of sensors, the readings of which are displayed on the computer monitor. You don't have to leave your workplace to determine the conditions in the server room. All information in the form of tables and graphs goes to the computer. Messages are accompanied by a sound signal.

Split systems

Column air conditioner device diagram

To maintain the specified parameters in the server rooms, split systems are used. Household or semi-industrial high-power systems are installed in small rooms with a heat release of up to 10 kW. By the type of installation, they are:

  • Wall mounted - a versatile and affordable option. Productivity is 2.5-5 kW, a model is selected in which a significant length of the freon line is provided. Recommended manufacturers are Daikin, Toshiba and Mitsubishi Electric.
  • Ducted - devices are placed under a false ceiling, save space and provide effective air exchange. Suitable for large server rooms. Ducted air conditioning supplies cold air directly to the racks.
  • Column - powerful systems in the form of cabinets are installed on the floor, do not require installation.

Split systems, in which winter operation is not provided, are being finalized with winter kits.

Precision climate systems

Server room precision air conditioners are professional equipment. Climatic complexes have a high resource of continuous operation, allow maintaining optimal temperature and humidity parameters. One of the advantages of the equipment is accuracy, climatic indicators in large premises have fluctuations of no more than 1 ° C and 2%. In server rooms, cabinet and ceiling models are installed. The first are distinguished by their bulky dimensions, their power is 100 kW. Ceiling systems are less efficient (20 kW) and are installed in rooms where it is not possible to place cabinet air conditioners.

Types of precision climatic devices

Climatic complexes can be monoblock and separate according to the type of split systems. The system is cooled in various ways: by evaporation of freon, water or air circuit. Popular manufacturers: UNIFLAIR, Blue box.

Pluses of installations:

  • uninterrupted work;
  • high power of equipment;
  • precise control of climatic components;
  • wide range of operating temperatures;
  • compatibility with dispatch control.

Cons of precision systems:

  • high price;
  • noisy monoblock design.

Chiller fan coil system

The air conditioning system uses water or an ethylene glycol mixture as the heating medium. The principle of operation is similar to installations with freon. The chiller cools the liquid circulating in the fan coil heat exchanger, and the air passing through the radiator lowers the temperature.

System advantages:

  • high performance;
  • versatility;
  • safe and affordable operation.

Air conditioner problems in winter

Subzero outside temperatures in winter lead to problems in the operation of air conditioning units:

  • The viscosity of the compressor oil increases, its properties deteriorate. At the moment of starting, the friction of the parts increases.
  • Icing of the fan blades of the outdoor unit.
  • Oil from the compressor dissolves in freon during constant operation.
  • In order to save money, the drain hose is removed to the street. At negative temperatures, the water in it freezes, forming a plug that prevents condensate drainage.

The solution to the problem is to choose an air conditioner for the server room with a winter kit. It includes:

  • Compressor crankcase heating cable. The oil becomes liquid, friction of parts is excluded, leading to rapid wear. A heating cable with a power of 30-50 W is installed at the bottom of the compressor.
  • The heating of the drain is carried out by a cable on the tube.
  • Outdoor fan speed controller. The electronic device is installed in the fan power supply break. The block regulates the speed from 0 to 100%. The speed is selected according to the readings of the temperature sensor.

Selection of an air conditioner by type of cooling

Depending on the area of ​​the room and the number of servers, one of the following cooling options is chosen:

  1. Air conditioning throughout the room. The disadvantage of this method is the uneven distribution of cold air. Due to low efficiency, electricity consumption increases.
  2. Zonal cooling of cabinets installed in rows. The cooler is either rack-mounted or an air-conditioned server cabinet is used. The air flow is blown out onto the equipment grates or into a cold aisle. The separation of the hot and cooled air zone allows to increase the efficiency of the system.
  3. Individual air conditioning with installation of a precision system on a server rack. The plant's productivity is used most efficiently. The disadvantage of this method is that the cost of such equipment is higher than other versions of climatic technology.

Selection and calculation of the power of the air conditioner

Calculation of the power of the air conditioner for the server room

The performance of climatic equipment is determined at the design stage of the server room. The calculations are based on the total heat emission of each cabinet. Indicators are taken from the equipment documentation. The calculations of the capacity of the air conditioner for the server room take into account the special requirements for the room and the operating modes of the equipment. The main criterion for choosing an air conditioner is cold performance. Its value should exceed the total heat release rate. You can use an online calculator on specialized sites. Accurate data will be required:

  • area of ​​the room;
  • ceiling height;
  • heat dissipation technology;
  • number of staff.

Formula for self-simplified calculation:

PQo + Qn + Qm, where

P is the power of the air conditioner;

Qo - heat dissipation of telecommunication equipment;

Qn - heat dissipation of people and auxiliary devices (uninterruptible power supplies, artificial lighting);

Qm - heat supply to the room from the environment.

In the absence of accurate data on server cabinets, heat dissipation is considered as 30-50% of power consumption. The volume (area) of the room is also taken into account when choosing an air conditioner. After calculating the required performance, redundancy is provided.

Do not forget that an increase in the power of the air conditioner leads to a rise in its cost.

home.techinfus.com/en/
Add a comment

Foundation

Ventilation

Heating