Air conditioners for server. A brief excursion in the cooling of server air conditioner problems in winter

At a certain point, some enterprises grow to the state when their internal information Systems Stop fit in one server cabinet. Then the head of the IT department will have to weigh all the "for" and "against" and decide whether to build or build a server. There may be several options: from full getting rid of their own capacities and lead them into the clouds or beokes in a large data center, before the construction of its own mini (or not very mini) of the blackjack.

The process of calculations, planning and construction of the server is very responsible and expensive. It will be invested at the project stage, here, by the way, you can save if all procedures in the server, from designing to construction, will produce one contractor. The natural desire of the head of the enterprise in such a situation is to meet the minimum possible amount. And in the bayonas perceived any increase in the cost of the project. In such vertaging, it is often forgotten that, in addition to the construction of an object, its content will be followed, which, with incorrect design, can be discussed by the budget of the enterprise to another non-existent server after two or three years.

The second largest consumer resources (in this case it is electricity and consumables) in the server is a cooling system. Neither the news is that the "power" of the cooling system of the server must match the minimum of the coincidence, and at best, to exceed a couple of dozen percent peak power of all equipment installed in the server. About which cooling systems are and how to save on the operation of such systems, we will talk in this article.

Classification of systems cooling systems

The most familiar to operate and understanding are compressor air conditioners. In them, refrigerant (in the overwhelming majority of cases - freon) transfers heat from the radiator inner block In the external, where it dissipates the energy environment. Read more about the principle of air conditioning, you can read. Then there are liquid and combined systems, water or ethylene glycol is used as the main refrigerant, and the selection of the coolant depends not only on operating conditions, as well as on the cooling method. And the most effective solution, in certain conditions, of course, are frekuling systems. These are exclusively precision devices that are developed almost from scratch in each particular case.

Also worth paying attention to the classification according to the "form factor". Here it is possible to divide systems into two types. Household systems that we are all already accustomed to, usually installed in offices and apartments, hanging on the walls or ceiling, but may well serve as systems for cooling specialized premises. And precision systems where specialized air conditioning systems can be attributed, and, of course, all frekuling and liquid systems.

Inside precision systems, there is a systematization on the principle of action and in the method of delivery "cold" to "consumers". And if with fundamental differences is increasingly less clear, then the methods of cooling directly the devices are a great set.

Among the classical generally accepted cases can be allocated cold room With installed racks, household air conditioners are also suitable. Classic options Precision solutions are devices with row air ducts, with cold and hot corridors, where racks stand in rows in such a way as to take cold air incoming, for example, from under Falsefol. They give the heated air into the corridors, from where it is forcibly allocated. There are also options with air ducts to each rack, where the air is supplied to each individual rack from above or below and then is also actively selected.

Nexlassical solutions a little more than a lot. It is necessary to say that they are all precision. Most solutions are a combination of the above-mentioned systems to improve efficiency and reduce costs. The scatter here is from individual air conditioners to each server cabinet to the liquid cooling of each individual server or even the processor. And also it is necessary to highlight systems with direct contact of the consumer with liquid. In this case, the server is fully immersed in special oil. Butter is odorless and absolutely does not conduct electricity. The liquid is constantly circulating inside the basins with the equipment, and passes through the cooling radiators.

Strategy

Not once it is worth thinking about the need to build a server. It is believed that for power less than 5kW, the selected server room is not needed. Usually, all the equipment is quite "will fall" in the 42-47-unite rack-cabinet, and the maximum that will still need it - this is a separate one-frame rack under the cross. All this can be burned from the "admin" or some other premises (the main thing not from the accounting) glass or plasterboard partition With a hermetic door, put a paired household air conditioner and go drink beer.

But we build a server. First of all, we need to decide which cooling system we will use, and the matter is not only in price. The choice of cooling method depends on the set of factors: the power of the equipment, the location of the server room in the building, the geographical location of the building itself and even from the prevailing attitude to certain types of cooling devices and short-sightedness.

It is common that the systems up to 10kW are quite enough of a household air conditioner. It is also clear, because household split systems of greater power, firstly, it is quite problematic to buy, and secondly, their cost is approaching, and then exceeds the cost of similar precision air conditioners.

From the location of the server room in the building, the possibility of installing a system of cooling, the ability to sum up communication, air ducts for specialized systems, arrange a falsefield or to establish turbines. In case of insufficient height of the ceilings, it is impossible to arrange a falsefield of the desired depth, to install the air ducts and air of the precision system. The position in the middle of the building will create problems when laying air ducts, one of the options for a frekuling system, and the neighborhood with the Economic Department will put the cross on the construction of the server because of "Nazhumit".

The geographical factor plays one of the paramount roles and often puts the cross on frekuling capabilities if you are, for example, in a tropical belt. That is why Codo builders love the northern regions of our planet so much, because there can not use air conditioners at all.

In addition to all, some technical experts have their own very hard belief in the applicability of one system and the absolute unacceptability of other cooling options. They will be calm and confident to prove their rightness, finding the arguments "for" and looking for the shortcomings of other sentences, from real to the mythical.

As a result, pushing off from the selected strategy, we will design the device itself.

Cooling strategy with household air conditioners

You are the owner of a small server park, 2-3 racks with which will stand in a separate room. You do not have the prospects for smooth power growth and you, or do not want to bother or (which is most likely) Do not have a budget for more energy efficient and environmentally friendly solutions.

First of all, decide how the rack with equipment relative to air conditioners will be located in your server. The best of the options in your case will be the installation of the internal modules of the split-system opposite the row of the racks one above one, directed to the "front" side of the open rack or a cabinet with a mesh door. Equipment inside the rack makes sense to set the side with which it takes air to cool the internal components. Some devices installed in the rack can be rebuilt or even produced in execution when they are either taken or emit air from the front side, or into one of the side walls. Think about it when buying.

Even if the growth of total power is not expected, air conditioners should be taken with a power supply, for example, taking a peak consumption-dispersion of the "hot" rack itself and by changing them, racks, quantity.
Minimum fault tolerance in this strategy - n + 1. In practice, it looks like two and more air conditioners of the same power, where "n" air conditioners can support operating temperature In the server while "+1" belt or serviced. Most often, two units are used in small server. To extend the resource of both air conditioners, it is necessary to use the rotation device of air conditioners. The device during certain periods of time switches to work from one air conditioner to another, tracks their launches and controls performance. At the failure of one of the air conditioners, it should automatically connect the "sleeping" and notify the responsible about the problem. It is worth noting that this function is not supported by all models of household air conditioners.

All server split systems installed in the latitudes of our country must have the so-called "Winter Set". It is a board of a board, some improvement in the radiator of the external unit of the air conditioner and the system of heating the pump crankcase. Works automatically.

Fig.1. Cooling with household air conditioners.

Precision system cooling systems

Precision (high-precision) air conditioner (or other cooler) - created as accuracy to work as efficiently as possible in infrastructure with specified finite parameters. In other words, when we say "precision air conditioning", we mean that the room, and the equipment of the server, and the "Refrigeration Installation" itself are developed in the project, as a set of technologies that make it possible to best ensure the performance, preservation and durability of expensive equipment.

Do I need to say that devices individual design - Pleasure is expensive. The sacred wars go between adherents of different camps. Some claim that for the usual server room there is a sufficiently spray industrial version of the household air conditioner, such as, for example, Daikin (FT and FAQ series) or Mitsubishi (Series Heavy). When choosing this option, it is important to take into account such minuses as local hot air wets in corners or in units of racks that are not engaged in active equipment. No less dangerous factor is low humidity, because, as you know, air conditioning, dries air. Dry air contributes to the accumulation of static electricity, the presence of static potential on fine electronics has a negative impact on the work of chips, and increases the risk of their destruction by the discharge. Sure, most of Factors are eliminated, but in most cases it is crutzing production. Additional fans, air humidifiers, these are all multiple points of failure, electricity costs and maintenance. Service, by the way, the same moisturizer, it's not so much costly for the means as in time. Need regular cleaning and daily topping water.

Precision, not everything is too smooth. First of all, they are very overall: freon air conditioners have dimensions of two or three full-size racks. Since humidity control is one of the main functions of a specialized air conditioner, then the internal blocks need to bring water, which is completely unacceptable for some IT Schnikov. Cold air from such aggregates is supplied to the racks through the ducts, which are conducted or under the raised floor, the most frequent and most expensive option, or under the ceiling, which implies high ceilings and imposes additional restrictions on the cable communications laying. Capacitors-coolers of such air conditioners have decent sizes, and immediately arises the question with their placement and liner of the pipe system from the inner block.

With the minuses ended, we turn to the pros. It can be attributed here: high performance, reservers only active components of the air conditioner (for example, air ducts, I think there is no point in presenting), clear control of temperature and humidity, the possibility of detailed monitoring. Pluses The following from here is relative savings, guaranteed cold air delivery to consumer, support high density Consumers per rack (it is rather a rule if the rack is empty, it will work inefficiently and influence the entire "ecosystem"). There is a completely explaining relationship between increasing costs of air conditioning and subsequent energy efficiency.

As I said, the most common phenomenon of precision air conditioning is the corridor system where the racks are located rows and are installed so as to pick up air from cold corridors (where air is supplied with air conditioning) and give it to hot (where the air is selected by the ventilation system). The air duct of such a system most often serves as a raised floor. The panel of the floor itself is mainly solid, all cable communications are transferred under the facility from under the festival, the lattice panels are arranged in front of the rows of racks in the floor, from where the cooled air enters the front side of the rack. Doors of server cabinets with such a device are made by mesh with both ends, or or do not do at all. Then the air is heated by servers blown into a hot corridor from where the system of forced ventilation is suused. Ideally, following the principles of thermodynamics, the hood is worth it to position at the top of the hot corridor, but often do it in a raised floor to save space over the struts for laying cable communications. With relatively recently, cold and hot corridors began to make hermetic from the general room of the server. This was achieved to achieve significant savings on the dispersion of valuable cold. In the free unit spaces of the cabinets, it is necessary to install the plugs, because the hot air does so strive to mix with the cooled. This can increase the cooling efficiency in one and a half or twice.

Fig. 2. System S. open corridorsObviously the loss of precious cold air.

Fig. 3. A more efficient, system with isolated corridors.

Intel, for example, pursuing the idea as simple as possible and efficiently cool the equipment, went further and even patented a rack with an exhaust. The rack is an ordinary 19 "cabinet, but deeper analogs and has an air duct in the top cover, opening into the space of a false-brake, from where the hot air is sucked by air conditioners. The whole system, in addition to air conditioners, is absolutely passive. But at the same time, according to Intel, it is capable of cooling 32 kW Rack equipment.

Taking into account the climate of our country, the precision air conditioners have another big plus: their diagram can be improved enough to refine, adding a complete or partial liquid circuit. Using ethylene glycol as refrigerant, parallel to the air conditioner contour build another loop with liquid cooling, thereby reducing the cost of electricity, air conditioning service and increasing the service life of these. The efficiency of the glycolic contour begins at temperatures below +20 s, which even in the summer at night in Russia is not at all uncommon.

An additional liquid circuit duplicates such freon, and in principle it can work around the clock, in the day "roast" time, cooling the air conditioner compressor and the condenser, and when the outdoor temperature drops, turning into partial and complete cooling of the internal heat exchanger.

The leaders among manufacturers of precision cooling systems are Schneider Electric, Stulz, Emerson Network Power, RC Group. Among their solutions there are ready-made combined systems.

Liquid systems

The fundamental difference of liquid cooling and freon only is that in the circuit, the liquid does not change the phase state in the circuit, which is why the water and glycolic systems are equal to the power of the system in efficiency. However, liquid systems have indisputable advantages, such as capacity and versatility. In liquid cooling systems, the cooler can be both a fancoon on the roof or in the courtyard of the building and the system of heating the building itself. The liquid can cool the air in the server, and can be used as a refrigerant for a separate processor. The indisputable advantage of liquid air conditioning is a practically unlimited length of the TRAC, due to the low price of the refrigerant, for the same system it is only a plus. The most dangerous in this situation is the leakage of a conductive agent, but, apparently, it does not scare anyone. IBM in this situation distinguished himself with the construction of SuperMUC, where 40% of energy savings achieved due to the absence in the cooling system of chillers. And Google in most of its dwarves and at all use the system of its own development, where the system of cold and hot corridors is used.

Another liquid system implies server immersion in special mineral oil. Oil - dielectric, so that the closure will not be. As for energy efficiency, according to the allegations of specialists of the same Intel, the cooling system in this case is spent by 90% less energy, and the power consumption of the servers themselves is reduced. Racks for submersible liquid cooling are already available, for example, by Sarnotjet. Racks are suitable for accommodating any servers, it is only pre-needed to pull out all the fans from them.

Fig. 4. The most liquid cooling

Another factor of universality is great amount refrigerant cooling methods. For example, you can cite Seawater Air Conditioning (SWAC) technology, a Google Data Center in Finland has been built on this technology. It is clear from the name that to cool the water entering the data center, the heat exchanger is used on cold waterclosed with sea depths.

The classic liquid cooling system acts as an intermediary between relatively high temperatures inside the room by the server and the cooler, which is more often a dry cooling tower and chiller, outside.

A dry cooling is a closed cooling circuit, where the fluid enters the radiator, which is forcibly blown by air. There are still wet coolies, the water is sprayed in them and at the same time blows. In the midstairs, or fancakely, the liquid refrigerant is usually only prepared by cooling to the air temperature, the chiller heat exchanger itself occurs.

Chiller is a refrigerator, it acts on Freon, cooling fluid passing through its cooler to the desired temperature.

For classic liquid air conditioning, all the same rules are true as for systems on Freon. The air cooled in the evaporator passes through consumers and selected from the server of the cooling system. Despite the fact that liquid systems are more versatile and generally cheaper in operation than freon, the effectiveness of them is lower due to the larger number of air-chiller-fluid intermediaries. Agree, not the most successful scheme.

We remove intermediaries

Direct Fryriculing is the most energy efficient way to cool the server. Of course, its effectiveness depends entirely on air temperature "overboard", but some changes in standardization and various green technologies are gradually moving the server cooling systems precisely in this direction.

Let's start with the fact that the largest standardizer of engineering systems, and in particular, cooling and heating systems, ASHRAE (English. American Society of Heating, Refrigerating and Air-Conditioning Engineers) - American Society for Heating Engineers, Cooling and Air Conditioning, since 2004 Twice increased the recommended air temperature for the cooling of the server from +22 to +27 degrees C. And in 2011, amendments to the standard were amended, stratifying two new equipment for server A3 and A4, where the temperature range was increased to +40 and +45 degrees. . Server manufacturers already produce such models. Although they have not yet become widespread, more and more builders are inclined to use green technologies in cooling.

For server services in our latitudes, freuciling can be if not fully replaced the classic cooling model, then a serious help in cooling in the cold season, and will also reduce the power of air conditioners.
The biggest problem of direct frekuling is the overall air pollution in the cities. It may happen that the amount, filter consumption and the power of the fans to produce them can reduce all the savings on electricity and power. This problem is solved by the separation of contours and the introduction between the heat exchanger based on a rotary heat exchanger. In this case, the filters will also be needed, but cheaper and with minimal air resistance.

Another big problem is that, with the auxiliary function of our freucolecher, it will be badly combined with household systems and is best with precision.

Of the advantages: with direct freiculant there is no risk to cut the air in the room with a server, because There is a permanent exchange of air with external environment. On the other hand, air humidity on the street can categorically not to meet the adopted humidity standards for server rooms, and here one of the main trumps of frekuling systems is coming to the aid - adiabatic cooling.

Long ago noted wet air The reservoirs are always cooler than the plains in remote from them, remember at least sea breeze. For adiabatic air cooling, it does not need neither system redundancy systems technical solutions. They are arranged according to the principle of wet cooling, in the heated outer air in the chambers of the nozzles, water is sprinkled, which evaporating cool and moisturizes the air. This system Not only effectively lowers the temperature of the external air, but also creates the necessary humidity. True, a new consumable material appears in such systems. Therefore, on the equal Pue (Power Usage Effectiveness), ASHRAE introduced a new WUE term (Water Usage Effectiveness (PDF)). For what corresponds to these parameters, I think it is clear to all.

As bright examples of the introduction of such systems, you can mention the data center "Mercury" in Phoenix (USA) and Facebook in Parenville (USA).

Instead of imprisonment

"So how do you still cool the small server for a couple of dozen kVA?" - you ask.
The answer is ambiguous. Most readers will suit the solution from two normal household air conditioners. Those who can convince their own leadership in the need to save and introduce environmentally friendly innovations, will receive a sea of \u200b\u200bheadache and then infinite pleasure end result.

As I said, a specific solution strongly depends on the climatic conditions of a particular region. To perceive the climatic picture, it is best to take historical certificate In terms of maxima and low temperature and humidity, in the entire history of instrumental observations in your region or city, as well as analyze detailed data on the hottest temperatures in the last 10-20 years. This is more than enough to work out a clear strategy.

Despite all the advantages of frekuling, in conditions middle stripIn 80 cases from 100, it is not likely to do without compressor or liquid air conditioner. Concerning, general idea Building a "big" energy-efficient server is as follows:

• This room with a precision cooling system. Indoors are arranged raised floors for the supply of cold air, with a division into cold and hot corridors, isolated from the general room by the server to ensure a clearer heat exchange.
• Most of the time, the system operates on a direct freuciling, an adiabatic cooling system is connected with an increase in the temperature of the external air. Upon exceeding the permissible norms on the humidity temperature, the system of compressor or liquid cooling is connected, i.e. air conditioning.

The adiabatik is not considered so interesting from the technical and practical point of view here in view of its specificity, it requires a more subtle approach to implementation. As for the option under consideration, it is obvious that energy efficiency in the future will require large investments at the construction stage.

It is worth paying attention to the fact that such a system will not be able to work without adequate and detailed monitoring of the state of the inner medium. Monitoring the temperature in cold and hot corridors, air humidity inside and outside, the presence of water in the adiabatic system, leak control. To do this, there are monitoring devices capable of publishing data from various sensors via Ethernet or WiFi. They are presented in the form of boards, enclosures and products for installation in the standard 19 "racks. For example, Netping is already equipped with a built-in GSM modem with an SMS module that can notify the significant changes in the parameters or the sensor triggering not only the responsible cooling system nodes, but also You personally.

In addition, all this data is not only possible, but also need to be entered into a global monitoring system, for example, Zabbix, where, according to schedules and samples, you can analyze the temperature map of the server, correlate changes inside the server and outside. Automate the creation of incidents based on the totality of indicators, and not on some one.

All this will allow you to rebuild the cooling system for maximum efficiency and prevent its breakdown.
Unfortunately, in one small article it is impossible to thoroughly work the topic of cooling the server. On the one hand, it may seem that freiculing is a way out for everyone, but in fact, this is a fairly risky enterprise. The story knows decently the number of epic situations when whole centles were outlined due to errors in designing and insufficient attention to detail. The best, though more expensive, is a solution that implies the duplication of standard cooling systems alternative.
Large codes, and incessant noise in server.

The trouble-free operation of electrical and electronic equipment depends on many technical solutions, including from effective protection against exposure to external climatic factors. To prevent the formation of condensate and adjust the temperature inside the cabinet, climate control devices are used. Highlight three main problems:

1. When heating devices occurs temperature increase Inside the electrical cabinet, which leads to overheating and output of equipment.
2. Many devices are not designed to work at low temperatures - At a minimum, the effectiveness of their work is reduced, but often such adverse external conditions lead to breakage.
3. As already noted above, inside the cabinet, the equipment heats up and the temperature increases. In case the cabinet is installed in an unheated room, with such temperature drops condensate is formedwhich leads to a short circuit.

Heating cabinet automation using FHL heaters

For heating electrical and telecommunication cabinets apply. Such products released, which offers two types of FLH series devices: convection heaters and heaters with a built-in fan. The latter have greater heating capacity and provide a more efficient distribution of heat flux inside cabinets with electrical and electronic filling. FLH heaters are convenient in the installation and easy to use.

FLH heaters

Control of temperature and humidity using thermostats and hygrostats FLZ

In addition to the heaters, the FLZ series must be installed as controls. PFANNENBERG hygrostats are intended to control the relative humidity with a range of installation from 40% to 90%. If the set value is exceeded, the hygrostat starts the fan with the filter or heater. And to maintain a constant temperature inside the cabinet, thermostats are used.

Often, combined devices are responsible for performing these functions. gigrostat / thermostat. For example, FLZ 610 devices, the installation of which allows you to significantly save space in the closet.

Combined device Gigrostat / thermostat FLZ 610

Cooling cabinet using PF fans or air conditioners DTI, DTS, DTT, RTM

If indoors where the electrotechnical cabinet is installed ambient temperature is lower than the maximum permissible temperature inside the cabinet at 10 ° C, then be able to provide optimal climatic conditions inside the electric cabinet. The cooling air fence occurs through the filter due to the fan. Removal of the air heated in the cabinet occurs through the outlet filter.

Cooling forced ventilation

The degree of protection of filters (intake and graduation) from influences ambient - IP54 or IP55. The filter housings and fans version of IP55 are resistant to ultraviolet radiation.

Installation of fans and filters is extremely simple - the equipment is fixed in pre-prepared rectangular holes with their own latches. To eliminate the occurrence of local overheating areas, it is recommended to disseminate the fan and exhaust filter for the maximum possible distances, and the fans should be placed at the bottom of the cabinets, and the outlet filters in the top. The replacement of the filter elements is not much difficult and will take no more pair of minutes.

If the outer air can not be used for coolingYou should apply (air conditioners) of the following series: DTI, DTS, DTT, RTM.

When selecting a cooling device, you should consider the required cooling power QO [W] and method of installation:

• DTS. - Air conditioners for mounted installation or mounting on the door. For those cases when there is no free space for air conditioning inside the control cabinet.
• Dti - Air conditioners for partially recessed mounting on the side surface or door.
• DTT. - Air conditioners with 100% condensate protection for saving installation location on the roof of the control cabinet.
• Ptm. - Air conditioners for use in small control cabinets.

Installation options: DTI, DTS and DTT

One of the species industrial premises is the server room in which important technical objects are located responsible for communicating with the company with foreign world and its information base. These include computers, servers, telecommunication equipment and other electronics. All these devices allocate a large amount of heat that, if not deleted, will create conditions, destructive for the normal functionality of the entire equipment.

In addition, regardless of its size, the server room requires compliance with strict regulations relative to certain air parameters (humidity, dustiness). If they are not supported year-round, then expensive electronic equipment fails. Therefore, properly designed air conditioning of server rooms is one of the first tasks that stands in their arrangement.

Is it possible to use a split system of air conditioning in the server

What climatic systems are used for these purposes, and from which this choice depends?

In small rooms with a limited number of computer equipment, household and semi-industrial split systems are most often set: wall, channels and columns (sometimes ceiling). Additionally provide duplicate climatic system In case of breakdown, the main in the form of 50% or 100% substitution. This has to add low-temperature sets for cooling in winter And to introduce many elements that increase the likelihood of breakdowns throughout the system.

Basic Disadvantages

A few more flaws in the air conditioning of server rooms Split systems are:

• inaccuracy of temperature maintenance;
• excessive drainage of air, from which unnecessary electrocolization occurs;
• appearance excess dust (it is very dangerous for servers) due to a weak fan and an inefficient filtering system;
• lowering efficiency due to energy consumption for condensation of the allocated moisture;
• fast development of resource with round-the-clock and year-round work.

The split-system usually does not provide for the possibility of functioning with such a load, therefore the performance limit exhausts itself in a year at 50% of reservation and after two at 100%.

Advantages of precision air conditioners for server rooms

More expensive, but at the same time, the installation of precision air conditioners belonging to professional climate equipment is considered a more reliable option. They are one of the types of cabinet blocks and are ideal for premises, where it is important not only to keep the specified temperature with maximum accuracy, but also to give air a certain percentage of humidity.

The main part of precision air conditioners for the server is characterized by such advantages compared to splits of semi-industrial purposes, as:

• accurate temperature control (+ 1 ° C) and moisture control (+ 2 ° C);
• year-round uninterrupted work;
• operation with limit heat and frost;
• combining with dispatch control and management systems.

Some precision air conditioners for server are capable of working with the thermometer values \u200b\u200boutside the building from + 60 ° C to -60 ° C.

The classification of precision junctions is very diverse and depends on many aspects. There are models with a monoblock design and by type of split-system. If we take into account the cooling method, the systems with the evaporation of freon and the system with water and air cooling of the capacitor, with air-cooled and the glycolic circuit, with a double cooling system and others are distinguished.

The famous company has a precision wardrobe with an energy-saving mode of operation, which can consume electricity in half less than others by using natural cooling without refrigeration cycle and inclusion of compressors.

The standard precision consists of a frame with automation, heat exchangers, filters, fans, elements of a refrigeration circuit and a power electric. From above it is closed with panels that protect it from external influences. If the presence of an outer block is provided, it can be executed as a compressor-capacitor unit or a remote condenser with air-cooled.

The principle of operation of this type of installation is not very complicated:

• the air is closed by the device either out of the room, or outside;
• inside cooled;
• he is given the required percentage of moisture;
• then it is produced outside the room.

Air fence can go from below or from above.

Selection of the air conditioner for the server according to the installation of the room

What to install the air conditioner in the server and what parameters it is selected?

Depending on the area of \u200b\u200bthe server, the number of electronics and its heat dissipation, experts provide 3 cooling options:

• all area in general;
• each number of servers separately;
• each server cabinet or rack individually.

General cooling server

The first method seems to be quite effective - the server room can be conditioned by any precision device or even semi-industrial split. The air is ejected either simply into the room, or by means of the outdoor false structure with straight to the server equipment.

But with this situation there are many minuses, the main of which is the unevenness of the discrepancy of chilled air. Due to the mixing of warm and cold flows, the efficiency is reduced and an increase in electricity consumption to normalize the desired temperature. Only small rooms can be cooled by general cooling.

Zonal cooling of server cabinets air conditioning

More reasonable is the air conditioning of server cabinets in the rows, that is, the processing is zero. Each unit is responsible for cooling a specific area with servers. This can occur both with the help of a special built-in cooler in the rack, and through the server cabinet with air conditioning bundled. Plus the fact that there are no individual fans here, and energy efficiency is completely not reduced.

We are talking about climate control in server and data center using inter-rigorous or intracetic air conditioners, which can be installed in an already existing SC. They serve air directly to servers. Unlike cabinet devices, blowout the flow occurs on the lattices of server installations or in a cold corridor.

More productive conditioning of a number of server cabinets and racks occurs during the insulation of hot and cold air corridors from each other. Also to achieve the maximum effect, the server cabinet with air conditioning should be completely sealed - you can not even allow the slightest losses of the cold.

If the solution is made to use the built-in cooler, then in addition to it, you will need a compressor-condenser unit of the outer installation.

Individual air conditioning cabinets and racks

What air conditioning is needed for a separate server rack or cabinet? As a rule, for individual cooling of each server installation, modular systems or high-power monoblock installations are used. They are easily mounted on the door of the server cabinet or on the wall. There are models for mounting on the rack rack or on the top cover of the cabinet. Heated and cooled air moves in a separate space inside without going out.

The efficiency and energy efficiency of the precision air conditioner for the server rack are very high, and the power potential is used without loss, so it is precisely such a type of air conditioning of server cabinets is considered the most rational.

Minus - the price of this type of equipment is much larger than the remaining refrigeration units above. But the need to establish a modular air conditioner in the rack occurs quite rarely and only in large rooms with the most powerful equipment that makes a huge amount of heat.

In server - it is always very responsible stages of designers and mounting work. Only experienced specialists will be able to make everything without mistakes and material losses, since the described type of service requires complex engineering solutions.

December 2018.

Why in server air conditioning?

A simple question for which every ITDSPECIALIST will answer.

Servers are heated: all electrical energy is transformed into thermal. Overheating is fraught with a decrease in performance and failure.

Selection of air conditioner for server

So, air conditioning in server - This is a need. It remains to understand which air conditioning you need: first by power, then - by type, everything is simple here.

The system unit selects 100% of consumption in the form of thermal energy. Consumption data can be obtained from the passport, while the incomplete loading coefficient is laid: 0.9-0.8. Average by 10.0 kW. The rated power of the exit power consumption is 8.5 kW. Heat. Without his lead (a set of cooling measures with exhaust ventilation and heat removal with air conditioning), then the room warms up, the fan will drive. warm air, the heat transfer of which is significantly lower. The result is overheating equipment.

When organizing the air conditioning of the server room, climatic companies are faced with three main problems:

1. The need for year-round cooling.

The air conditioner should work regardless of the temperature of the external air. It is not for everyone. Only the best models can work out 24 hours a day all winter when minus temperatures . Frozen oil contained in Freon, the efficiency is reduced, wear increases. This must be provided.

2. The need for uninterrupted cooling.

Failure in the operation of the air conditioning system is possible overheating and disable equipment. Scary sleep of the system administrator!

According to the SNiP 41-01-2003 pp.7.2.3, "Community ventilation systems for production, administrative and public premises with a permanent stay of people without natural ventilation should be provided for at least two aircraft and two exhaust fans Each consumption of at least 50% of the required air exchange. It is allowed to provide one inlet and one exhaust system With backup fans or with backup electric motors for administrative and domestic and public premises. "

Implementation of this scheme thing is costly. In small server rooms, it is bypass with a simple household air conditioner with a winter set, which has a 75-100% reserve for cooling power. Those. On the server cabinet with a heat generation of 3 kW. Installing air conditioning 5.0-6.0 kW. Option is more expensive, but more adequate in terms of safety and durability of equipment is installation of 2 air conditioners with a block of control of their alternate work.

3. The need to maintain the specified parameters of humidity.

It is usually provided with complex, semi-industrial systems - precision air conditioners designed not only to cool the room, but also support set parameters Air humidity! But a description of such such complex systems Not included in the tasks of this superficial article.

From the "ready-made" solutions, you can only find options for small server rooms with heat release to 10 kW. Here it is quite possible to do with ordinary split systems, modified.

We are extremely recommended, based on your many years of experience and troubled statistics on equipment failures, install equipment such as Mitsubishi Electric, Fujitsu, Daikin, Toshiba. Having heated the room is unlikely to be needed (the server is so warm), then it is better to install and cheaper blocks that work only on the cold, however, some "by default" producers produce models working on cold, and heat.

Contact managers: We will help in the selection of the desired model both in technical and according to the cost characteristics. For you - this is one of the tasks. For us - everyday work! Believe me, we will do good offer. Yes, and do everything perfectly!

As an example, to estimate the size of the costs further presents several models of the best Japanese manufacturers: Daikin and Mitsubishi Electric.

If the budget does not withstand Japanese brands, we will offer not bad factory China. More and more server work on Chinese rules. And ... work well. Yes, without fantastic efficiency. But they are an order of magnitude less.

Split System Model	Cooling, kW.	Price	Installation
Daikin FTYN25L / RYN25L NORD-30	2.5	47370 R.	7000 rub.
Daikin ATXN25M6 / ARXN25M6 NORD -30	2.6	49800 R.	5000 rub.
Daikin FTYN35L / RYN35L NORD-30	3.27	49640 R.	7000 rub.
Daikin ATXN35M6 / ARXN35M6 NORD -30	3.3	52800 R.	5000 rub.
Daikin FTYN50L / RYN50L NORD-30	5.35	66050 R.	7000 rub.
Daikin ATXN50M6 / ARXN50M6 NORD -30	5.7	72800 R.	7000 rub.
Daikin FTYN60L / RYN60L NORD-30	6.01	74690 R.	7000 rub.
Daikin ATXN60M6 / ARXN60M6 NORD -30	6.3	75800 R.	7000 rub.
Daikin FAQ71B / RQ71BV NORD-30	7.1	187851 R.	14900 rub.
Daikin FAQ100B / RQ100BV NORD-30	10.0	213633 R.	14900 rub.

Split System Model	Cooling, kW.	Price	Installation
MITSUBISHI ELECTRIC MS-GF25VA / MU-GF25VA / -30	2.5	48590 R.	7000 rub.
MITSUBISHI ELECTRIC MS-GF35VA / MU-GF35VA / -30	3.4	69640 R.	7000 rub.
MITSUBISHI ELECTRIC MS-GF50VA / MU-GF50VA / -30	5.1	81640 R.	9000 rub.
MITSUBISHI ELECTRIC MS-GF60VA / MU-GF60VA / -30	6.0	95640 R.	9000 rub.

Uninterrupted operation of the server room cooling system is ensured by reserving and / or power reserve.

• First, if heat generations make up, for example, 7 kW., It is desirable to install split systems, at least 2 blocks, by 9 kW. So that no system does not enter the limit modes of operation to save the resource;
• Secondly, the installation of a backup unit, which can cool the room during a breakdown of one single or one of the two main air conditioners;
• Third, the cooling control automation. The simplest scheme is to turn on / off the equipment using a block of alternating work on 2 independent air conditioners. Alternation of steam and single cooling work.

Cassette air conditioners in server

Channel air conditioner in server

Air conditioner equipment for server winter set

Winter air conditioner kit Consists of 3 components:

• regulator of the speed of rotation of the fan of the compressor condenser unit of the air conditioner. This is one of the main, most complex technically performed parts of the winter kit. The main purpose is to slow down the fan. He should not allow airborne evaporator by air with a temperature of +30 degrees and -20 with the same intensity;
• compressor crankcase heater. The goal is to heat the oil in the freon to ensure the lubrication of the rubber components of the compressor. Otherwise, the metal chips is inevitable. And this is an increase in the clearance of parts, a violation of the centering, an increase in the amplitude of oscillations with a further complete output of the compressor;
• heating drainage drainage. The formation of condensate in the internal block is a side effect of air conditioning. And now imagine that the moisture, which goes outside the drain tube, hits the frost.

For large server, as well as for cooling, mining farms often apply channel air conditioning, providing address distribution of air to racks

In order not to cool the entire room, the whole cold air is supplied directly to the equipment using channel air conditioners. The internal block of the channel air conditioner carries out air ducts and cooling it back. With such a scheme, cooling costs are somewhat reduced, the server contamination is reduced, the same amount of air is cleaned through the cabinet, purified by the filters of the inner block of the split-system with a slight addition of air from outside.

Summing up air ducts OT. channel air conditioners To server racks

Effective cooled air distribution between racks with equipment

Installation of channel air conditioners for cooling equipment

Channel air conditioning system mining farm at 210 kW.

More complex objects require the execution of detailed calculations and selection of equipment that is often supplied to the order on a specific object. In conclusion, I also want to note: yes, precision air conditioners with humidity control, cleanliness and air temperature are the top of perfection. Installing a similar system allows you to completely get rid of the risk of equipment outlet due to external reasons. But the cost of installing and installing it is very high and make this step cost-effective only in large server with a huge amount of information, in server, where not just a loss (most of the data are reserved in principle), and the simple stop of the equipment causes enormous costs.

In the server rooms of medium-sized companies, it is quite reasonable to take advantage of the divided system of domestic purposes (wall, cassette, channel, etc.), improved winter sets and, if necessary, a block of control of alternate operation when installing two or more air conditioners.

Well, in the tiny server rooms of small providers or small companies with their own server (on 2-3 powerful PCs), conventional mobile air conditioners are often installed: cheap and angry. Again: any option has the right to implement, when choosing, focus on the budget.

In any case, we will gladly help in solving the problem of cooling the server room. Air conditioning in the server is, as already talked, the need for any company. Data value, a whole office downtime due to overheating protection, are incommensurable with the cost of equipment and its installation.

Service Split Systems

And I would also like to note: whom you would not have ordered air conditioning - do not forget to carry out regular service! After all air conditioner in server running constantly, passing every hour through myself hundreds of cubic meters of air, which leads to clogging of the heat exchanger and evaporator. And this is fraught with overheating and compressor output. Periodic service (twice a year) will significantly extend the life of the split system.

Pay attention to the degree of pollution. Dirty block - a sharp decline in the efficiency!

Honestly: we did not throw dirt. This is the real state of many split systems.

Cassette air conditioning. So far did not flow out of the pallet - we were not called. In vain.

Believe me, it's cheaper than each year install a new air conditioner for cooling servers! In addition, we provide services for the installation of new systems that have failed in order (sometimes recovery costs, comparable to buying a new air conditioner) on the existing route with and without flushing the highway (some series).