Calculating Server Room Heat Loads

Emergency Portable Cooling System
March 22, 2010
Portable Air Conditioners: How they can help your business
May 16, 2010
Show all

Calculating Server Room Heat Loads

Priceless corporate data and tens of thousands of dollars of server room equipment can quickly be at risk for loss if server room temperatures aren’t maintained correctly. Because server room equipment releases so much more heat than any other office location, portable air conditioners are the ideal solution for cooling the server room by being location specific with your critical cooling requirements.

Server room cooling needs

Before purchasing air conditioners for a server room, you’ll need to calculate how much heat must be displaced. With the excessive amount of heat produced by the server room equipment, you can’t choose a portable air conditioner based on the general square foot recommendations alone. Instead, you’ll need to pay attention to the entire BTUs generated in the server room.

In principle it’s easy to calculate the size of air conditioning unit you’ll need for your server room just add together all the sources of heat and install an air conditioning unit that can remove that much cooling. In practice however, it’s rather more complicated.

Calculating The Heat Load

The amount of heat generated is known as heat gain or heat load. Heat is measured in either British Thermal Units (BTU) or Kilowatts (KW).

1 KW is equivalent to 3412 BTUs. 12000 BTU = 1 Ton of Cooling Capacity

Factors Include:

  • The floor area of the room
  • The size and position of windows, and whether they have blinds or shades
  • The number of room occupants (if any)
  • The heat generated by equipment
  • The heat generated by lighting

To calculate the heat load you will need the following information.Room Area BTU = Length (m) x Width (m) x 337

    • South Window BTU = South Facing window Length (m) x Width (m) x 870
    • North Window BTU = North Facing windows Length (m) x Width (m) x 165
    • If there are no blinds on the windows multiply the result(s) by 1.5.
    • Windows BTU = South Window(s) BTU + North Window(s) BTU
    • Total Occupant BTU = Number of occupants x 400
    • Equipment BTU = Total wattage for all equipment x 3.5
    • Lighting BTU = Total wattage for all lighting x 4.25

Total Cooling Required

Add all the BTUs together

Room Area BTU + Windows BTU + Total Occupant BTU + Equipment BTU + Lighting BTU = Total Heat Load

Total Heat Load divided by 12000 = Total Cooling Tonnage

For example if the calculated BTU = 16400 BTU then 16400/12000 = 1.36 Total Cooling tonnage required. Since the requirement is 1.36 Tons you would consider using our SCT18, 1.5 Ton unit to cool your server room.

Choosing A Unit:

Portable air conditioners, also called spot coolers, are ideal for server room cooling because they focus a lot of cooling energy exactly where it’s needed.


What type of outlet power is available?

Spot Cooling Systems, Inc. makes this calculation simple.

Our 1 Ton SCT14 and 1.5 Ton SCT18 units operate off standard 115 volt, 60 Hz, 1 phase, power on a 15 Amp circuit.

Our 2.5 Ton SCT30, 3.5 Ton SCT42 and 6.5 Ton SCT83 operate pm 208-230 Volt, 60Hz, 1 phase power on a 20, 30, 60 Amp circuit respectively.

The 5.4 Ton ECHD65 operates on 208-230 Volt, 60 Hz, 3 phase power on a 40amp circuit and the 6.5 Ton SCT83B unit uses 460 Volt, 60 Hz, 3 phase power on a 20 Amp circuit.

Is Your Server Room Firewalled?

All Spot Cooling Systems portable air conditioners discharge the heat removed form the room to an open ceiling cavity. In the case of a firewalled server room that heat has nowhere to escape. The simple solution to this is to install a firewall damper to which duct work can be attached to allow heated air to discharge to an open location.

Designed for portability and convenience, EXTRACOOLER® portable air conditioners set up in minutes and roll easily from the shop floor to offices areas.  The EXTRACOOLER® air-cooled portable air conditioner line consists of six models, offering from 14,000-77.500 BTU/hr.

Cools Quietly. EXTRACOOLER® cools quietly at office-acceptable sound levels without significantly addition to background noise.  Ideal for supplemental of temporary cooling in server rooms, offices, meeting areas, or classrooms, Featuring backward-inclined plenum evaporator and condenser fans, EXTRACOOLER’s® operate at the lowest decibel level for portable air conditioners.

Cools Effectively. EXTRACOOLER® delivers a full performance at a wide range of temperatures and altitudes with a thermostatic-expansion valve – not found in ordinary units.  This valve automatically adjusts to the environment, allowing the units to operate under more extreme temperatures.

Cools Efficiently. Just plug in an EXTRACOOLER®  and cool – no special electrical requirements are needed.  Most EXTRACOOLER models are single phase (460V 3 Phase option on the TZ-60A4).  EXTRACOOLER® costs less to operate because it draws the least amount of amperage on a per-ton basis when compared to ordinary industrial air conditioners