Short answer
Server room cooling means keeping devices that constantly generate heat, such as servers, network switches, recorders and UPS units within the manufacturer's specified temperature range. In a Şanlıurfa summer, a single office-type air conditioner is often not enough; the room's heat load should be calculated, hot and cold air should be separated, and a backup against air conditioner failure and a temperature alarm should be set up.
Why does a server room get hot?
Every electrically powered device turns almost all the power it uses into heat. When a cabinet full of network devices, servers and a UPS runs day and night, a small room heats up quickly. People leave when the workday ends; the devices do not.
In Şanlıurfa's long, hot summer the building also heats up from the outside. A server room next to a sun-facing wall or on the top floor gains heat even if the devices inside are not running. When these two factors add up, the problem usually appears in the afternoons of July and August.
A small room does not make things easier. In a small room, the same heat spreads into less air and the temperature rises faster. Cabinets placed under a staircase or in small rooms used as storage are therefore the most problematic examples.
Signs of overheating
A heat problem in the server room is often not directly visible. The symptoms appear like some other fault:
If one of these symptoms repeats, before replacing the faulty part it is a good idea to measure the room temperature for a few days. A disk or device that is replaced without solving the heat problem may fail again under the same conditions.
- The recorder or server restarts on its own in the afternoons.
- The fans are constantly at high speed, with a noticeable roar in the room.
- The network connection drops at certain hours.
- Disks fail earlier than expected.
- UPS batteries swell or lose capacity quickly.
- The back of the cabinet is too hot to touch.
Why is an office air conditioner not enough?
Office-type split air conditioners are designed for people's comfort: they run during the day, switch off, remove humidity, and stop when they reach a set temperature. A server room, on the other hand, produces a constant, steady heat load. An office air conditioner wears out faster when forced to run continuously.
The second problem is air distribution. The air conditioner blows cold air into one corner of the room, while cabinets take in air at the front and exhaust it hot at the back. If the cold air mixes with the hot air before it reaches the front of the cabinet, the inside of the devices heats up while the room thermometer reads normal.
Third, many office air conditioners do not turn back on by themselves when power goes out and comes back. After a short outage over the weekend, the air conditioner stays off and nobody notices.
The fourth problem is humidity. While cooling the air, the air conditioner also removes humidity; air that is too dry or too humid is undesirable for devices. Air conditioners designed for server rooms control temperature and humidity together.
Expert note: Check whether the air conditioner has a feature to turn back on by itself after power returns (automatic restart). Using an air conditioner without this feature in a server room is risky.
- Heat load calculated
- Air conditioner restarts automatically
- Front of the cabinet cold, back hot
- Blanking panels fitted in empty slots
- Backup air conditioner or alternating operation
- Temperature sensor and notification
- Filters cleaned regularly
- Room is in a place that gets no sun
What needs to be done for proper cooling
First the heat load is calculated: the total power of the devices in the room, the size of the room, and the sun-facing walls and windows. The air conditioner capacity is chosen according to this calculation. An air conditioner chosen by guess is either insufficient or oversized and switches on and off often.
Then the airflow is arranged. The front of the cabinets should face the side the cold air comes from, and the back should face the side the hot air leaves. If empty slots inside the cabinet are closed with blanking panels, hot air does not return to the front. Cables should not pile up behind the cabinet and block the air path.
For the operating temperature of servers and storage devices, the range in the manufacturer's technical document should be taken as the basis. Take the measurement in front of the cabinet, at the point where the device draws in air. The room thermometer by the door does not show this value.
The air conditioner's blowing direction should also be checked. If cold air is blown directly to the back of the cabinet, that is, the side where hot air comes out, the two air masses mix and the cooling is wasted.
Redundancy and monitoring
In a server room with a single air conditioner, an air conditioner failure means the servers heat up and shut down. In critical systems, two air conditioners are installed and run in rotation; when one fails, the other takes over. Running in rotation evens out the wear on both units.
A temperature and humidity sensor continuously measures conditions in the room and sends a notification to the responsible person when the set limit is exceeded. The alert from this sensor should reach someone outside working hours as well. The same monitoring system can also track water leaks, door openings and the UPS status.
Dust is a separate issue in Şanlıurfa. In a server room with a door that opens often or a window, dust collects in the device fans and the air conditioner's filter. The door should be kept closed, the windows should be sealed, and the filters should be cleaned regularly.
Air conditioner maintenance should be done before summer arrives. Cleaning the filter, checking the gas, and making sure the area around the outdoor unit is clear reduce the risk of a breakdown on the hottest days. If the front of the outdoor unit is blocked by items or sits in direct sun, its efficiency drops.
What not to do in the server room
Many heat problems come from wrong use. No matter how good the installation is, if the room turns into a storage space over time, cooling becomes insufficient.
- Using the room as storage for boxes, old equipment, and files
- Putting devices in a closed cabinet with no ventilation
- Blocking the air the air conditioner blows with a curtain or a box
- Leaving the door open for ventilation
- Turning the air conditioner off at night to save energy
- Not recalculating the cooling capacity when adding new devices
Expert note: Before adding a new server or recorder, ask: how much heat will this device add to the room, and can the existing air conditioner handle it?
When planning a new server room
If possible, the server room should be placed in an interior room of the building that gets no sun. Attic floors, the southwest facade, and areas where water pipes run should be avoided. The location of the air conditioner's outdoor unit and where the condensate water will drain should be planned from the start.
When deciding the room size, leave space for cabinets to be added in the future. If the capacity of the air conditioner and the electrical panel is also chosen for this growth, you will not need to rearrange the whole room to add new devices a few years later.
In server room installations, Desa Bilişim handles the cabinet, power, cooling, and monitoring together; the heat load calculation is done with an on-site inspection.
Frequently asked
What temperature should a server room be?
Rather than giving a single number, look at the operating range given in the technical documents of the devices in the room. What matters is not the room average but the temperature in front of the cabinet, at the point where the device draws in air.
Is a fan enough in a small office?
If there is only a modem and a small switch, a well-ventilated cabinet may be enough. When a server, recorder or UPS is added, and when the room temperature rises in summer, a fan is not enough; an air-conditioned environment is needed.
How do we notice an air conditioner failure?
A temperature sensor and a notification system should be installed. The sensor sends an alert by email or message when the set limit is exceeded. That way a failure that happens outside working hours is noticed in time.
Let's get your server room ready for summer
Tell us about the devices in the room and the problem you are having, and we will assess the heat load on site.
