Server room air con sizing calculation

The high heat gains and expense of replacing burnt out computer equipment makes reliable server room air conditioning an essential requirement. Typically a server room would need to be maintained at 22oC and between 40-60% relative humidity.

Server room air conditioner size calculation
In order to calculate the size of air conditioner that you require you will need to know:

The floor area of the room
The size and position of the windows
The number of occupants (if any)
The heat generated by the equipment in watts
The heat generated by the lights in watts

Once you have this information perform the following calculation:

Room area (length in m x width in m) x 337
Length (m) x width (m) of south facing window x 870
Length (m) x width (m) of north facing window x 165
(if there are no blinds on the windows multiply windows results by 1.5, also if you are in the southern hemisphere reverse these conversion factors so a south facing is x 165 and a north facing is 870))
Number of occupants x 400
Wattage for all equipment, e.g. servers, switches and routers x 3.5
(the wattage for equipment is based on maximum power consumption)
Lighting wattage x 4.25

Add all your results together and divide by 3412. This is the size of air conditioner you require in kW.

Server room air conditioning issues
- If you are going to install a wall-mounted split system then this will involve installing a fan unit in the room to be cooled and an external unit on an outside wall. Most regions in the UK do not require you to obtain planning permission for this type of installation but some do. You will need to check with your local council if you are unsure

- Always try to install the inside fan unit of a split system on an external wall as it removes the need to run piping along walls and can make condensate removal much easier as a condensate pump may not be required - a gravity drain can be used instead.

- If the air conditioner goes down for any reason it could mean that the server stops working and therefore your company. As it is such a vital piece of equipment many companies install a back-up system in case of emergencies.

- Always oversize an air conditioning system as computer hardware is often upgraded and added to in server rooms. An increase in the heat gain may overload the air conditioner during very hot weather. This is also the time when air conditioning companies are at their busiest and response times may be longer than normal causing major disruptions to your business' IT.

- Always remember to get your air conditioner serviced every six months in order to maintain efficiency and prolong product life.

- When positioning your unit remember you will need to access it when servicing takes place.

- Air conditioning will dry an atmosphere. Always maintain a humidity of above 40% relative humidity in a server room otherwise static electrical build-up could damage sensitive electrical equipment. If your humidity is dropping below this point install a humidifier. Click the Humidifiers link on the menu on the left for more info on our range.